Life
Temporal range: 3770–0 Ma Pha. Proterozoic Archean Had’n Archean – Present (possible Hadean origin) |
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Diversity of Prokaryota which includes Archaea, Cyanobacteria, Bacillus, Campylobacteria, Enterobacteria, Diplococcus, and Spirochete |
Diversity of Eukaryota which includes Gray wolf, Giant sequoia, Entodinium, Amanita caesarea, Pterois antennata, Algae blooms, Chrysotoxum verralli, Xanthoparmelia lichen, Dictyostelium, and Pillar coral |
Scientific classification |
Domains and Supergroups |
Life on Earth:
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Life is a quality that distinguishes matter that has biological processes, such as signaling and self-sustaining processes, from matter that does not, and is defined by the capacity for growth, reaction to stimuli, metabolism, energy transformation, and reproduction.[2][3] Various forms of life exist, such as plants, animals, fungi, protists, archaea, and bacteria. Biology is the science that studies life.
The gene is the unit of heredity, whereas the cell is the structural and functional unit of life.[4][5] There are two kinds of cells, prokaryotic and eukaryotic, both of which consist of cytoplasm enclosed within a membrane and contain many biomolecules such as proteins and nucleic acids. Cells reproduce through a process of cell division, in which the parent cell divides into two or more daughter cells and passes its genes onto a new generation, sometimes producing genetic variation.
Organisms, or the individual entities of life, are generally thought to be open systems that maintain homeostasis, are composed of cells, have a life cycle, undergo metabolism, can grow, adapt to their environment, respond to stimuli, reproduce and evolve over multiple generations. Other definitions sometimes include non-cellular life forms such as viruses and viroids, but they are usually excluded because they do not function on their own; rather, they exploit the biological processes of hosts.[6][7]
Abiogenesis, also known as the origin of life, is the natural process of life arising from non-living matter, such as simple organic compounds. Since its primordial beginnings, life on Earth has changed its environment on a geologic time scale, but it has also adapted to survive in most ecosystems and conditions. New lifeforms have evolved from common ancestors through hereditary variation and natural selection, and today, estimates of the number of distinct species range anywhere from 3 million to over 100 million.[3][8]
Death is the permanent termination of all biological processes which sustain an organism, and as such, is the end of its life. Extinction is the term describing the dying-out of a group or taxon, usually a species. Once extinct, the extinct species or taxon cannot come back to life. Fossils are the preserved remains or traces of organisms.
Definitions
The definition of life has long been a challenge for scientists and philosophers.[9][10][11] This is partially because life is a process, not a substance.[12][13][14] This is complicated by a lack of knowledge of the characteristics of living entities, if any, that may have developed outside of Earth.[15][16] Philosophical definitions of life have also been put forward, with similar difficulties on how to distinguish living things from the non-living.[17] Legal definitions of life have also been described and debated, though these generally focus on the decision to declare a human dead, and the legal ramifications of this decision.[18] As many as 123 definitions of life have been compiled.[19]
Biology
Since there is no consensus for a definition of life, most current definitions in biology are descriptive. Life is considered a characteristic of something that preserves, furthers or reinforces its existence in the given environment. This characteristic exhibits all or most of the following traits:[11][20][21][2][22][23][24]
- Homeostasis: regulation of the internal environment to maintain a constant state; for example, sweating to reduce temperature
- Organisation: being structurally composed of one or more cells – the basic units of life
- Metabolism: transformation of energy by converting chemicals and energy into cellular components (anabolism) and decomposing organic matter (catabolism). Living things require energy to maintain internal organisation (homeostasis) and to produce the other phenomena associated with life.
- Growth: maintenance of a higher rate of anabolism than catabolism. A growing organism increases in size in all of its parts, rather than simply accumulating matter.
- Adaptation: the evolutionary process whereby an organism becomes better able to live in its habitat or habitats.[25][26][27]
- Response to stimuli: a response can take many forms, from the contraction of a unicellular organism to external chemicals, to complex reactions involving all the senses of multicellular organisms. A response is often expressed by motion; for example, the leaves of a plant turning toward the sun (phototropism), and chemotaxis.
- Reproduction: the ability to produce new individual organisms, either asexually from a single parent organism or sexually from two parent organisms.
These complex processes, called physiological functions, have underlying physical and chemical bases, as well as signaling and control mechanisms that are essential to maintaining life.
Alternative definitions
From a physics perspective, living beings are thermodynamic systems with an organised molecular structure that can reproduce itself and evolve as survival dictates.[28][29] Thermodynamically, life has been described as an open system which makes use of gradients in its surroundings to create imperfect copies of itself.[30] Another way of putting this is to define life as «a self-sustained chemical system capable of undergoing Darwinian evolution», a definition adopted by a NASA committee attempting to define life for the purposes of exobiology, based on a suggestion by Carl Sagan.[31][32][33] This definition, however, has been widely criticized because according to it, a single sexually reproducing individual is not alive as it is incapable of evolving on its own.[34] The reason for this potential flaw is that «NASA’s definition» refers to life as a phenomenon, not a living individual, which makes it incomplete.[35] Alternative, definitions based on the notion of life as a phenomenon and a living individual have been proposed as continuum of a self-maintainable information, and a distinct element of this continuum, respectively. A major strength of this approach is that it defines life in terms of mathematics and physics, avoiding biological vocabulary, which inevitably leads to pleonasticity.[35]
According to self-maintainable information’s theory, entities are given gradually more alive status, with gaining the ability to evolve and maintaining distinctness.
Others take a systemic viewpoint that does not necessarily depend on molecular chemistry. One systemic definition of life is that living things are self-organizing and autopoietic (self-producing). Variations of this definition include Stuart Kauffman’s definition as an autonomous agent or a multi-agent system capable of reproducing itself or themselves, and of completing at least one thermodynamic work cycle.[36] This definition is extended by the apparition of novel functions over time.[37]
Viruses
Whether or not viruses should be considered as alive is controversial. They are most often considered as just gene coding replicators rather than forms of life.[38] They have been described as «organisms at the edge of life»[39] because they possess genes, evolve by natural selection,[40][41] and replicate by making multiple copies of themselves through self-assembly. However, viruses do not metabolise and they require a host cell to make new products. Virus self-assembly within host cells has implications for the study of the origin of life, as it may support the hypothesis that life could have started as self-assembling organic molecules.[42][43][44]
Biophysics
To reflect the minimum phenomena required, other biological definitions of life have been proposed,[45] with many of these being based upon chemical systems. Biophysicists have commented that living things function on negative entropy.[46][47] In other words, living processes can be viewed as a delay of the spontaneous diffusion or dispersion of the internal energy of biological molecules towards more potential microstates.[9] In more detail, according to physicists such as John Bernal, Erwin Schrödinger, Eugene Wigner, and John Avery, life is a member of the class of phenomena that are open or continuous systems able to decrease their internal entropy at the expense of substances or free energy taken in from the environment and subsequently rejected in a degraded form.[48][49] The emergence and increasing popularity of biomimetics or biomimicry (the design and production of materials, structures, and systems that are modelled on biological entities and processes) will likely redefine the boundary between natural and artificial life.[50]
Living systems theories
Living systems are open self-organizing living things that interact with their environment. These systems are maintained by flows of information, energy, and matter.
Definition of cellular life according to Budisa, Kubyshkin and Schmidt
Budisa, Kubyshkin and Schmidt defined cellular life as an organizational unit resting on four pillars/cornerstones: (i) energy, (ii) metabolism, (iii) information and (iv) form. This system is able to regulate and control metabolism and energy supply and contains at least one subsystem that functions as an information carrier (genetic information). Cells as self-sustaining units are parts of different populations that are involved in the unidirectional and irreversible open-ended process known as evolution.[51]
Some scientists have proposed in the last few decades that a general living systems theory is required to explain the nature of life.[52] Such a general theory would arise out of the ecological and biological sciences and attempt to map general principles for how all living systems work. Instead of examining phenomena by attempting to break things down into components, a general living systems theory explores phenomena in terms of dynamic patterns of the relationships of organisms with their environment.[53]
Gaia hypothesis
The idea that Earth is alive is found in philosophy and religion, but the first scientific discussion of it was by the Scottish scientist James Hutton. In 1785, he stated that Earth was a superorganism and that its proper study should be physiology. Hutton is considered the father of geology, but his idea of a living Earth was forgotten in the intense reductionism of the 19th century.[54]: 10 The Gaia hypothesis, proposed in the 1960s by scientist James Lovelock,[55][56] suggests that life on Earth functions as a single organism that defines and maintains environmental conditions necessary for its survival.[54] This hypothesis served as one of the foundations of the modern Earth system science.
Self-maintainable information
All living entities posess genetic information that maintains itself by processess called cis-actions.[35] Cis-action is any action that has an impact on the initiator, and in chemical systems is known as the autocatalytic set. In living systems, all the cis-actions have generally a positive influence on the system as those with negative impact are eliminated by natural selection. Genetic information acts as an initiator, and it can maintain itself via a series of cis-actions like self-repair or self-production (the production of parts of the body to be distinguished from self-reproduction, which is a duplication of the entire entity). Various cis-actions give the entity additional traits to be considered alive. Self-maintainable information is a basic requirement — a level zero for gaining lifeness and it can be obtained by any cis-action like self-repair (like a gene coding a protein that fixes alteration to a nucleic acid caused by UV radiation). Subsequently, if the entity is able to perform error-prone self-reproduction it gains the trait of evolution and belongs to a continuum of self-maintainable information — it becomes part of the living world in meaning of phenomenon but not yet a living individual. For this upgrade, the entity has to process the trait of distinctness, understood as an ability to define itself as a separate entity with its own fate. There are two possible ways of reaching distinctness: 1) maintaining an open-system (a cell) or/and 2) maintaining a transmission process (for obligatory parasites). Fulfiling any of these cis-actions raises the entity to a level of living individual — a distinct element of the self-maintainable information’s continuum. The final level regards the state of the entity as dead or alive and requires the trait of functionality.[35]
This approach provides a lather-like hierarchy of entities depending on their ability to maintain themselves, their evolvability, and their distinctness. It also distinguishes between life as a phenomenon, a living individual, and an alive individual.[35]
Nonfractionability
Robert Rosen devoted a large part of his career, from 1958[57] onwards, to developing a comprehensive theory of life as a self-organizing complex system, «closed to efficient causation».[note 5] He defined a system component as «a unit of organization; a part with a function, i.e., a definite relation between part and whole.» He identified the «nonfractionability of components in an organism» as the fundamental difference between living systems and «biological machines.» He summarised his views in his book Life Itself.[58] Similar ideas may be found in the book Living Systems[59] by James Grier Miller.
Property of ecosystems
A systems view of life treats environmental fluxes and biological fluxes together as a «reciprocity of influence,»[60] and a reciprocal relation with environment is arguably as important for understanding life as it is for understanding ecosystems. As Harold J. Morowitz (1992) explains it, life is a property of an ecological system rather than a single organism or species.[61] He argues that an ecosystemic definition of life is preferable to a strictly biochemical or physical one. Robert Ulanowicz (2009) highlights mutualism as the key to understand the systemic, order-generating behaviour of life and ecosystems.[62]
Complex systems biology
Complex systems biology (CSB) is a field of science that studies the emergence of complexity in functional organisms from the viewpoint of dynamic systems theory.[63] The latter is also often called systems biology and aims to understand the most fundamental aspects of life. A closely related approach to CSB and systems biology called relational biology is concerned mainly with understanding life processes in terms of the most important relations, and categories of such relations among the essential functional components of organisms; for multicellular organisms, this has been defined as «categorical biology», or a model representation of organisms as a category theory of biological relations, as well as an algebraic topology of the functional organisation of living organisms in terms of their dynamic, complex networks of metabolic, genetic, and epigenetic processes and signalling pathways.[64][65] Alternative but closely related approaches focus on the interdependence of constraints, where constraints can be either molecular, such as enzymes, or macroscopic, such as the geometry of a bone or of the vascular system.[66]
Darwinian dynamic
It has also been argued that the evolution of order in living systems and certain physical systems obeys a common fundamental principle termed the Darwinian dynamic.[67][68] The Darwinian dynamic was formulated by first considering how macroscopic order is generated in a simple non-biological system far from thermodynamic equilibrium, and then extending consideration to short, replicating RNA molecules. The underlying order-generating process was concluded to be basically similar for both types of systems.[67]
Operator theory
Another systemic definition called the operator theory proposes that life is a general term for the presence of the typical closures found in organisms; the typical closures are a membrane and an autocatalytic set in the cell[69] and that an organism is any system with an organisation that complies with an operator type that is at least as complex as the cell.[70][71][72][73] Life can also be modelled as a network of inferior negative feedbacks of regulatory mechanisms subordinated to a superior positive feedback formed by the potential of expansion and reproduction.[74]
History of study
Materialism
Herds of zebra and impala gathering on the Maasai Mara plain
Some of the earliest theories of life were materialist, holding that all that exists is matter, and that life is merely a complex form or arrangement of matter. Empedocles (430 BC) argued that everything in the universe is made up of a combination of four eternal «elements» or «roots of all»: earth, water, air, and fire. All change is explained by the arrangement and rearrangement of these four elements. The various forms of life are caused by an appropriate mixture of elements.[75]
Democritus (460 BC) thought that the essential characteristic of life is having a soul (psyche). Like other ancient writers, he was attempting to explain what makes something a living thing. His explanation was that fiery atoms make a soul in exactly the same way atoms and void account for any other thing. He elaborates on fire because of the apparent connection between life and heat, and because fire moves.[76]
Plato’s world of eternal and unchanging Forms, imperfectly represented in matter by a divine Artisan, contrasts sharply with the various mechanistic Weltanschauungen, of which atomism was, by the fourth century at least, the most prominent … This debate persisted throughout the ancient world. Atomistic mechanism got a shot in the arm from Epicurus … while the Stoics adopted a divine teleology … The choice seems simple: either show how a structured, regular world could arise out of undirected processes, or inject intelligence into the system.[77]
— R.J. Hankinson, Cause and Explanation in Ancient Greek Thought
The mechanistic materialism that originated in ancient Greece was revived and revised by the French philosopher René Descartes (1596–1650), who held that animals and humans were assemblages of parts that together functioned as a machine. This idea was developed further by Julien Offray de La Mettrie (1709–1750) in his book L’Homme Machine.[78]
In the 19th century the advances in cell theory in biological science encouraged this view. The evolutionary theory of Charles Darwin (1859) is a mechanistic explanation for the origin of species by means of natural selection.[79]
At the beginning of the 20th century Stéphane Leduc (1853–1939) promoted the idea that biological processes could be understood in terms of physics and chemistry, and that their growth resembled that of inorganic crystals immersed in solutions of sodium silicate. His ideas, set out in his book La biologie synthétique[80] was widely dismissed during his lifetime, but has incurred a resurgence of interest in the work of Russell, Barge and colleagues.[81]
Hylomorphism
Hylomorphism is a theory first expressed by the Greek philosopher Aristotle (322 BC). The application of hylomorphism to biology was important to Aristotle, and biology is extensively covered in his extant writings. In this view, everything in the material universe has both matter and form, and the form of a living thing is its soul (Greek psyche, Latin anima). There are three kinds of souls: the vegetative soul of plants, which causes them to grow and decay and nourish themselves, but does not cause motion and sensation; the animal soul, which causes animals to move and feel; and the rational soul, which is the source of consciousness and reasoning, which (Aristotle believed) is found only in man.[82] Each higher soul has all of the attributes of the lower ones. Aristotle believed that while matter can exist without form, form cannot exist without matter, and that therefore the soul cannot exist without the body.[83]
This account is consistent with teleological explanations of life, which account for phenomena in terms of purpose or goal-directedness. Thus, the whiteness of the polar bear’s coat is explained by its purpose of camouflage. The direction of causality (from the future to the past) is in contradiction with the scientific evidence for natural selection, which explains the consequence in terms of a prior cause. Biological features are explained not by looking at future optimal results, but by looking at the past evolutionary history of a species, which led to the natural selection of the features in question.[84]
Spontaneous generation
Spontaneous generation was the belief that living organisms can form without descent from similar organisms. Typically, the idea was that certain forms such as fleas could arise from inanimate matter such as dust or the supposed seasonal generation of mice and insects from mud or garbage.[85]
The theory of spontaneous generation was proposed by Aristotle,[86] who compiled and expanded the work of prior natural philosophers and the various ancient explanations of the appearance of organisms; it was considered the best explanation for two millennia. It was decisively dispelled by the experiments of Louis Pasteur in 1859, who expanded upon the investigations of predecessors such as Francesco Redi.[87][88] Disproof of the traditional ideas of spontaneous generation is no longer controversial among biologists.[89][90][91]
Vitalism
Vitalism is the belief that the life-principle is non-material. This originated with Georg Ernst Stahl (17th century), and remained popular until the middle of the 19th century. It appealed to philosophers such as Henri Bergson, Friedrich Nietzsche, and Wilhelm Dilthey,[92] anatomists like Xavier Bichat, and chemists like Justus von Liebig.[93] Vitalism included the idea that there was a fundamental difference between organic and inorganic material, and the belief that organic material can only be derived from living things. This was disproved in 1828, when Friedrich Wöhler prepared urea from inorganic materials.[94] This Wöhler synthesis is considered the starting point of modern organic chemistry. It is of historical significance because for the first time an organic compound was produced in inorganic reactions.[93]
During the 1850s Hermann von Helmholtz, anticipated by Julius Robert von Mayer, demonstrated that no energy is lost in muscle movement, suggesting that there were no «vital forces» necessary to move a muscle.[95] These results led to the abandonment of scientific interest in vitalistic theories, especially after Buchner’s demonstration that alcoholic fermentation could occur in cell-free extracts of yeast.[96]
Nonetheless, the belief still exists in pseudoscientific theories such as homoeopathy, which interprets diseases and sickness as caused by disturbances in a hypothetical vital force or life force.[97]
Origin
The age of Earth is about 4.54 billion years.[98][99][100] Evidence suggests that life on Earth has existed for at least 3.5 billion years,[101][102][103][104][105][106][107][108][109] with the oldest physical traces of life dating back 3.7 billion years;[110][111][112] however, some hypotheses, such as Late Heavy Bombardment, suggest that life on Earth may have started even earlier, as early as 4.1–4.4 billion years ago,[101][102][103][104][105] and the chemistry leading to life may have begun shortly after the Big Bang, 13.8 billion years ago, during an epoch when the universe was only 10–17 million years old.[113][114][115] Time estimates from molecular clocks, as summarized in TimeTree, generally place the origin of life around 4.0 billion years ago or earlier.[116]
More than 99% of all species of life forms, amounting to over five billion species,[117] that ever lived on Earth are estimated to be extinct.[118][119]
The Francevillian biota are thought by some to represent the oldest known (dated to around 2.1 billion years) examples of life, although some have suggested they may be pseudofossils of inorganic pyrite.[120]
Although the number of Earth’s catalogued species of lifeforms is between 1.2 million and 2 million,[121][122] the total number of species in the planet is uncertain. Estimates range from 8 million to 100 million,[121][122] with a more narrow range between 10 and 14 million,[121] but it may be as high as 1 trillion (with only one-thousandth of one per cent of the species described) according to studies realised in May 2016.[123][124] The total number of related DNA base pairs on Earth is estimated at 5.0 x 1037 and weighs 50 billion tonnes.[125] In comparison, the total mass of the biosphere has been estimated to be as much as 4 TtC (trillion tons of carbon).[126] In July 2016, scientists reported identifying a set of 355 genes from the Last Universal Common Ancestor (LUCA) of all organisms living on Earth.[127]
All known life forms share fundamental molecular mechanisms, reflecting their common descent; based on these observations, hypotheses on the origin of life attempt to find a mechanism explaining the formation of a universal common ancestor, from simple organic molecules via pre-cellular life to protocells and metabolism. Models have been divided into «genes-first» and «metabolism-first» categories, but a recent trend is the emergence of hybrid models that combine both categories.[128]
There is no current scientific consensus as to how life originated. However, most accepted scientific models build on the Miller–Urey experiment and the work of Sidney Fox, which show that conditions on the primitive Earth favoured chemical reactions that synthesize amino acids and other organic compounds from inorganic precursors,[129] and phospholipids spontaneously form lipid bilayers, the basic structure of a cell membrane.
Living organisms synthesize proteins, which are polymers of amino acids using instructions encoded by deoxyribonucleic acid (DNA). Protein synthesis entails intermediary ribonucleic acid (RNA) polymers. One possibility for how life began is that genes originated first, followed by proteins;[130] the alternative being that proteins came first and then genes.[131]
However, because genes and proteins are both required to produce the other, the problem of considering which came first is like that of the chicken or the egg. Most scientists have adopted the hypothesis that because of this, it is unlikely that genes and proteins arose independently.[132]
Therefore, a possibility, first suggested by Francis Crick,[133] is that the first life was based on RNA,[132] which has the DNA-like properties of information storage and the catalytic properties of some proteins. This is called the RNA world hypothesis, and it is supported by the observation that many of the most critical components of cells (those that evolve the slowest) are composed mostly or entirely of RNA. Also, many critical cofactors (ATP, Acetyl-CoA, NADH, etc.) are either nucleotides or substances clearly related to them. The catalytic properties of RNA had not yet been demonstrated when the hypothesis was first proposed,[134] but they were confirmed by Thomas Cech in 1986.[135]
One issue with the RNA world hypothesis is that synthesis of RNA from simple inorganic precursors is more difficult than for other organic molecules. One reason for this is that RNA precursors are very stable and react with each other very slowly under ambient conditions, and it has also been proposed that living organisms consisted of other molecules before RNA.[136] However, the successful synthesis of certain RNA molecules under the conditions that existed prior to life on Earth has been achieved by adding alternative precursors in a specified order with the precursor phosphate present throughout the reaction.[137] This study makes the RNA world hypothesis more plausible.[138]
Geological findings in 2013 showed that reactive phosphorus species (like phosphite) were in abundance in the ocean before 3.5 Ga, and that Schreibersite easily reacts with aqueous glycerol to generate phosphite and glycerol 3-phosphate.[139] It is hypothesized that Schreibersite-containing meteorites from the Late Heavy Bombardment could have provided early reduced phosphorus, which could react with prebiotic organic molecules to form phosphorylated biomolecules, like RNA.[139]
In 2009, experiments demonstrated Darwinian evolution of a two-component system of RNA enzymes (ribozymes) in vitro.[140] The work was performed in the laboratory of Gerald Joyce, who stated «This is the first example, outside of biology, of evolutionary adaptation in a molecular genetic system.»[141]
Prebiotic compounds may have originated extraterrestrially. NASA findings in 2011, based on studies with meteorites found on Earth, suggest DNA and RNA components (adenine, guanine and related organic molecules) may be formed in outer space.[142][143][144][145]
In March 2015, NASA scientists reported that, for the first time, complex DNA and RNA organic compounds of life, including uracil, cytosine and thymine, have been formed in the laboratory under outer space conditions, using starting chemicals, such as pyrimidine, found in meteorites. Pyrimidine, like polycyclic aromatic hydrocarbons (PAHs), the most carbon-rich chemical found in the universe, may have been formed in red giants or in interstellar dust and gas clouds, according to the scientists.[146]
According to the panspermia hypothesis, microscopic life—distributed by meteoroids, asteroids and other small Solar System bodies—may exist throughout the universe.[147][148]
Environmental conditions
The diversity of life on Earth is a result of the dynamic interplay between genetic opportunity, metabolic capability, environmental challenges,[149] and symbiosis.[150][151][152] For most of its existence, Earth’s habitable environment has been dominated by microorganisms and subjected to their metabolism and evolution. As a consequence of these microbial activities, the physical-chemical environment on Earth has been changing on a geologic time scale, thereby affecting the path of evolution of subsequent life.[149] For example, the release of molecular oxygen by cyanobacteria as a by-product of photosynthesis induced global changes in the Earth’s environment. Because oxygen was toxic to most life on Earth at the time, this posed novel evolutionary challenges, and ultimately resulted in the formation of Earth’s major animal and plant species. This interplay between organisms and their environment is an inherent feature of living systems.[149]
Biosphere
The biosphere is the global sum of all ecosystems. It can also be termed as the zone of life on Earth, a closed system (apart from solar and cosmic radiation and heat from the interior of the Earth), and largely self-regulating.[153] By the most general biophysiological definition, the biosphere is the global ecological system integrating all living beings and their relationships, including their interaction with the elements of the lithosphere, geosphere, hydrosphere, and atmosphere.
Life forms live in every part of the Earth’s biosphere, including soil, hot springs, inside rocks at least 19 km (12 mi) deep underground, the deepest parts of the ocean, and at least 64 km (40 mi) high in the atmosphere.[154][155][156] Under certain test conditions, life forms have been observed to thrive in the near-weightlessness of space[157][158] and to survive in the vacuum of outer space.[159][160] Life forms appear to thrive in the Mariana Trench, the deepest spot in the Earth’s oceans.[161][162] Other researchers reported related studies that life forms thrive inside rocks up to 580 m (1,900 ft; 0.36 mi) below the sea floor under 2,590 m (8,500 ft; 1.61 mi) of ocean off the coast of the northwestern United States,[161][163] as well as 2,400 m (7,900 ft; 1.5 mi) beneath the seabed off Japan.[164] In August 2014, scientists confirmed the existence of life forms living 800 m (2,600 ft; 0.50 mi) below the ice of Antarctica.[165][166] According to one researcher, «You can find microbes everywhere—they’re extremely adaptable to conditions, and survive wherever they are.»[161]
The biosphere is postulated to have evolved, beginning with a process of biopoesis (life created naturally from non-living matter, such as simple organic compounds) or biogenesis (life created from living matter), at least some 3.5 billion years ago.[167][168] The earliest evidence for life on Earth includes biogenic graphite found in 3.7 billion-year-old metasedimentary rocks from Western Greenland[110] and microbial mat fossils found in 3.48 billion-year-old sandstone from Western Australia.[111][112] More recently, in 2015, «remains of biotic life» were found in 4.1 billion-year-old rocks in Western Australia.[102][103] In 2017, putative fossilised microorganisms (or microfossils) were announced to have been discovered in hydrothermal vent precipitates in the Nuvvuagittuq Belt of Quebec, Canada that were as old as 4.28 billion years, the oldest record of life on Earth, suggesting «an almost instantaneous emergence of life» after ocean formation 4.4 billion years ago, and not long after the formation of the Earth 4.54 billion years ago.[169][170][171][172] According to biologist Stephen Blair Hedges, «If life arose relatively quickly on Earth … then it could be common in the universe.»[102]
In a general sense, biospheres are any closed, self-regulating systems containing ecosystems. This includes artificial biospheres such as Biosphere 2 and BIOS-3, and potentially ones on other planets or moons.[173]
Range of tolerance
The inert components of an ecosystem are the physical and chemical factors necessary for life—energy (sunlight or chemical energy), water, heat, atmosphere, gravity, nutrients, and ultraviolet solar radiation protection.[174] In most ecosystems, the conditions vary during the day and from one season to the next. To live in most ecosystems, then, organisms must be able to survive a range of conditions, called the «range of tolerance.»[175] Outside that are the «zones of physiological stress,» where the survival and reproduction are possible but not optimal. Beyond these zones are the «zones of intolerance,» where survival and reproduction of that organism is unlikely or impossible. Organisms that have a wide range of tolerance are more widely distributed than organisms with a narrow range of tolerance.[175]
Extremophiles
To survive, selected microorganisms can assume forms that enable them to withstand freezing, complete desiccation, starvation, high levels of radiation exposure, and other physical or chemical challenges. These microorganisms may survive exposure to such conditions for weeks, months, years, or even centuries.[149] Extremophiles are microbial life forms that thrive outside the ranges where life is commonly found.[176] They excel at exploiting uncommon sources of energy. While all organisms are composed of nearly identical molecules, evolution has enabled such microbes to cope with this wide range of physical and chemical conditions. Characterization of the structure and metabolic diversity of microbial communities in such extreme environments is ongoing.[177]
Microbial life forms thrive even in the Mariana Trench, the deepest spot in the Earth’s oceans.[161][162] Microbes also thrive inside rocks up to 1,900 feet (580 m) below the sea floor under 8,500 feet (2,600 m) of ocean.[161][163] Expeditions of the International Ocean Discovery Program found unicellular life in 120 °C sediment that is 1.2 km below seafloor in the Nankai Trough subduction zone.[178]
Investigation of the tenacity and versatility of life on Earth,[176] as well as an understanding of the molecular systems that some organisms utilise to survive such extremes, is important for the search for life beyond Earth.[149] For example, lichen could survive for a month in a simulated Martian environment.[179][180]
Chemical elements
All life forms require certain core chemical elements needed for biochemical functioning. These include carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur—the elemental macronutrients for all organisms[181]—often represented by the acronym CHNOPS. Together these make up nucleic acids, proteins and lipids, the bulk of living matter. Five of these six elements comprise the chemical components of DNA, the exception being sulfur. The latter is a component of the amino acids cysteine and methionine. The most biologically abundant of these elements is carbon, which has the desirable attribute of forming multiple, stable covalent bonds. This allows carbon-based (organic) molecules to form an immense variety of chemical arrangements.[citation needed] Alternative hypothetical types of biochemistry have been proposed that eliminate one or more of these elements, swap out an element for one not on the list, or change required chiralities or other chemical properties.[182][183]
DNA
Main article: DNA
Deoxyribonucleic acid is a molecule that carries most of the genetic instructions used in the growth, development, functioning and reproduction of all known living organisms and many viruses. DNA and RNA are nucleic acids; alongside proteins and complex carbohydrates, they are one of the three major types of macromolecule that are essential for all known forms of life. Most DNA molecules consist of two biopolymer strands coiled around each other to form a double helix. The two DNA strands are known as polynucleotides since they are composed of simpler units called nucleotides.[184] Each nucleotide is composed of a nitrogen-containing nucleobase—either cytosine (C), guanine (G), adenine (A), or thymine (T)—as well as a sugar called deoxyribose and a phosphate group. The nucleotides are joined to one another in a chain by covalent bonds between the sugar of one nucleotide and the phosphate of the next, resulting in an alternating sugar-phosphate backbone. According to base pairing rules (A with T, and C with G), hydrogen bonds bind the nitrogenous bases of the two separate polynucleotide strands to make double-stranded DNA. The total amount of related DNA base pairs on Earth is estimated at 5.0 x 1037, and weighs 50 billion tonnes.[125] In comparison, the total mass of the biosphere has been estimated to be as much as 4 TtC (trillion tons of carbon).[126]
DNA stores biological information. The DNA backbone is resistant to cleavage, and both strands of the double-stranded structure store the same biological information. Biological information is replicated as the two strands are separated. A significant portion of DNA (more than 98% for humans) is non-coding, meaning that these sections do not serve as patterns for protein sequences.
The two strands of DNA run in opposite directions to each other and are, therefore, anti-parallel. Attached to each sugar is one of four types of nucleobases (informally, bases). It is the sequence of these four nucleobases along the backbone that encodes biological information. Under the genetic code, RNA strands are translated to specify the sequence of amino acids within proteins. These RNA strands are initially created using DNA strands as a template in a process called transcription.
Within cells, DNA is organised into long structures called chromosomes. During cell division these chromosomes are duplicated in the process of DNA replication, providing each cell its own complete set of chromosomes. Eukaryotic organisms (animals, plants, fungi, and protists) store most of their DNA inside the cell nucleus and some of their DNA in organelles, such as mitochondria or chloroplasts.[185] In contrast, prokaryotes (bacteria and archaea) store their DNA only in the cytoplasm. Within the chromosomes, chromatin proteins such as histones compact and organise DNA. These compact structures guide the interactions between DNA and other proteins, helping control which parts of the DNA are transcribed.
DNA was first isolated by Friedrich Miescher in 1869.[186] Its molecular structure was identified by James Watson and Francis Crick in 1953, whose model-building efforts were guided by X-ray diffraction data acquired by Rosalind Franklin.[187]
Classification
Antiquity
The first known attempt to classify organisms was conducted by the Greek philosopher Aristotle (384–322 BC), who classified all living organisms known at that time as either a plant or an animal, based mainly on their ability to move. He also distinguished animals with blood from animals without blood (or at least without red blood), which can be compared with the concepts of vertebrates and invertebrates respectively, and divided the blooded animals into five groups: viviparous quadrupeds (mammals), oviparous quadrupeds (reptiles and amphibians), birds, fishes and whales. The bloodless animals were also divided into five groups: cephalopods, crustaceans, insects (which included the spiders, scorpions, and centipedes, in addition to what we define as insects today), shelled animals (such as most molluscs and echinoderms), and «zoophytes» (animals that resemble plants). Though Aristotle’s work in zoology was not without errors, it was the grandest biological synthesis of the time and remained the ultimate authority for many centuries after his death.[188]
Linnaean
The exploration of the Americas revealed large numbers of new plants and animals that needed descriptions and classification. In the latter part of the 16th century and the beginning of the 17th, careful study of animals commenced and was gradually extended until it formed a sufficient body of knowledge to serve as an anatomical basis for classification.
In the late 1740s, Carl Linnaeus introduced his system of binomial nomenclature for the classification of species. Linnaeus attempted to improve the composition and reduce the length of the previously used many-worded names by abolishing unnecessary rhetoric, introducing new descriptive terms and precisely defining their meaning.[189] The Linnaean classification has eight levels: domains, kingdoms, phyla, class, order, family, genus, and species.
The fungi were originally treated as plants. For a short period Linnaeus had classified them in the taxon Vermes in Animalia, but later placed them back in Plantae. Copeland classified the Fungi in his Protoctista, thus partially avoiding the problem but acknowledging their special status.[190] The problem was eventually solved by Whittaker, when he gave them their own kingdom in his five-kingdom system. Evolutionary history shows that the fungi are more closely related to animals than to plants.[191]
As new discoveries enabled detailed study of cells and microorganisms, new groups of life were revealed, and the fields of cell biology and microbiology were created. These new organisms were originally described separately in protozoa as animals and protophyta/thallophyta as plants, but were united by Haeckel in the kingdom Protista; later, the prokaryotes were split off in the kingdom Monera, which would eventually be divided into two separate groups, the Bacteria and the Archaea. This led to the six-kingdom system and eventually to the current three-domain system, which is based on evolutionary relationships.[192] However, the classification of eukaryotes, especially of protists, is still controversial.[193]
As microbiology, molecular biology and virology developed, non-cellular reproducing agents were discovered, such as viruses and viroids. Whether these are considered alive has been a matter of debate; viruses lack characteristics of life such as cell membranes, metabolism and the ability to grow or respond to their environments. Viruses can still be classed into «species» based on their biology and genetics, but many aspects of such a classification remain controversial.[194]
In May 2016, scientists reported that 1 trillion species are estimated to be on Earth currently with only one-thousandth of one per cent described.[123]
The original Linnaean system has been modified over time as follows:
Linnaeus 1735[195] |
Haeckel 1866[196] |
Chatton 1925[197] |
Copeland 1938[198] |
Whittaker 1969[199] |
Woese et al. 1990[192] |
Cavalier-Smith 1998[200] |
Cavalier-Smith 2015[201] |
---|---|---|---|---|---|---|---|
2 kingdoms | 3 kingdoms | 2 empires | 4 kingdoms | 5 kingdoms | 3 domains | 2 empires, 6 kingdoms | 2 empires, 7 kingdoms |
(not treated) | Protista | Prokaryota | Monera | Monera | Bacteria | Bacteria | Bacteria |
Archaea | Archaea | ||||||
Eukaryota | Protoctista | Protista | Eucarya | Protozoa | Protozoa | ||
Chromista | Chromista | ||||||
Vegetabilia | Plantae | Plantae | Plantae | Plantae | Plantae | ||
Fungi | Fungi | Fungi | |||||
Animalia | Animalia | Animalia | Animalia | Animalia | Animalia |
Cells
Cells are the basic unit of structure in every living thing, and all cells arise from pre-existing cells by division. Cell theory was formulated by Henri Dutrochet, Theodor Schwann, Rudolf Virchow and others during the early nineteenth century, and subsequently became widely accepted.[202] The activity of an organism depends on the total activity of its cells, with energy flow occurring within and between them. Cells contain hereditary information that is carried forward as a genetic code during cell division.[203]
There are two primary types of cells. Prokaryotes lack a nucleus and other membrane-bound organelles, although they have circular DNA and ribosomes. Bacteria and Archaea are two domains of prokaryotes. The other primary type of cells are the eukaryotes, which have distinct nuclei bound by a nuclear membrane and membrane-bound organelles, including mitochondria, chloroplasts, lysosomes, rough and smooth endoplasmic reticulum, and vacuoles. In addition, they possess organised chromosomes that store genetic material. All species of large complex organisms are eukaryotes, including animals, plants and fungi, though most species of eukaryote are protist microorganisms.[204] The conventional model is that eukaryotes evolved from prokaryotes, with the main organelles of the eukaryotes forming through endosymbiosis between bacteria and the progenitor eukaryotic cell.[205]
The molecular mechanisms of cell biology are based on proteins. Most of these are synthesised by the ribosomes through an enzyme-catalyzed process called protein biosynthesis. A sequence of amino acids is assembled and joined based upon gene expression of the cell’s nucleic acid.[206] In eukaryotic cells, these proteins may then be transported and processed through the Golgi apparatus in preparation for dispatch to their destination.[207]
Cells reproduce through a process of cell division in which the parent cell divides into two or more daughter cells. For prokaryotes, cell division occurs through a process of fission in which the DNA is replicated, then the two copies are attached to parts of the cell membrane. In eukaryotes, a more complex process of mitosis is followed. However, the result is the same; the resulting cell copies are identical to each other and to the original cell (except for mutations), and both are capable of further division following an interphase period.[208]
Multicellular organisms may have first evolved through the formation of colonies of identical cells. These cells can form group organisms through cell adhesion. The individual members of a colony are capable of surviving on their own, whereas the members of a true multi-cellular organism have developed specialisations, making them dependent on the remainder of the organism for survival. Such organisms are formed clonally or from a single germ cell that is capable of forming the various specialised cells that form the adult organism. This specialisation allows multicellular organisms to exploit resources more efficiently than single cells.[209] In January 2016, scientists reported that, about 800 million years ago, a minor genetic change in a single molecule, called GK-PID, may have allowed organisms to go from a single cell organism to one of many cells.[210]
Cells have evolved methods to perceive and respond to their microenvironment, thereby enhancing their adaptability. Cell signalling coordinates cellular activities, and hence governs the basic functions of multicellular organisms. Signaling between cells can occur through direct cell contact using juxtacrine signalling, or indirectly through the exchange of agents as in the endocrine system. In more complex organisms, coordination of activities can occur through a dedicated nervous system.[211]
Though life is confirmed only on Earth, many think that extraterrestrial life is not only plausible, but probable or inevitable.[212][213] Other planets and moons in the Solar System and other planetary systems are being examined for evidence of having once supported simple life, and projects such as SETI are trying to detect radio transmissions from possible alien civilisations. Other locations within the Solar System that may host microbial life include the subsurface of Mars, the upper atmosphere of Venus,[214] and subsurface oceans on some of the moons of the giant planets.[215][216]
Beyond the Solar System, the region around another main-sequence star that could support Earth-like life on an Earth-like planet is known as the habitable zone. The inner and outer radii of this zone vary with the luminosity of the star, as does the time interval during which the zone survives. Stars more massive than the Sun have a larger habitable zone, but remain on the Sun-like «main sequence» of stellar evolution for a shorter time interval. Small red dwarfs have the opposite problem, with a smaller habitable zone that is subject to higher levels of magnetic activity and the effects of tidal locking from close orbits. Hence, stars in the intermediate mass range such as the Sun may have a greater likelihood for Earth-like life to develop.[217] The location of the star within a galaxy may also affect the likelihood of life forming. Stars in regions with a greater abundance of heavier elements that can form planets, in combination with a low rate of potentially habitat-damaging supernova events, are predicted to have a higher probability of hosting planets with complex life.[218] The variables of the Drake equation are used to discuss the conditions in planetary systems where civilisation is most likely to exist.[219] Use of the equation to predict the amount of extraterrestrial life, however, is difficult; because many of the variables are unknown, the equation functions as more of a mirror to what its user already thinks. As a result, the number of civilisations in the galaxy can be estimated as low as 9.1 x 10−13, suggesting a minimum value of 1, or as high as 15.6 million (1.56 x 108); for the calculations, see Drake equation.
A «Confidence of Life Detection» scale (CoLD) for reporting evidence of life beyond Earth has been proposed.[220][221]
Artificial
Artificial life is the simulation of any aspect of life, as through computers, robotics, or biochemistry.[222] The study of artificial life imitates traditional biology by recreating some aspects of biological phenomena. Scientists study the logic of living systems by creating artificial environments—seeking to understand the complex information processing that defines such systems. While life is, by definition, alive, artificial life is generally referred to as data confined to a digital environment and existence.
Synthetic biology is a new area of biotechnology that combines science and biological engineering. The common goal is the design and construction of new biological functions and systems not found in nature. Synthetic biology includes the broad redefinition and expansion of biotechnology, with the ultimate goals of being able to design and build engineered biological systems that process information, manipulate chemicals, fabricate materials and structures, produce energy, provide food, and maintain and enhance human health and the environment.[223]
Death
Animal corpses, like this African buffalo, are recycled by the ecosystem, providing energy and nutrients for living creatures.
Death is the termination of all vital functions or life processes in an organism or cell.[224][225] It can occur as a result of an accident, violence, medical conditions, biological interaction, malnutrition, poisoning, senescence, or suicide. After death, the remains of an organism re-enter the biogeochemical cycle. Organisms may be consumed by a predator or a scavenger and leftover organic material may then be further decomposed by detritivores, organisms that recycle detritus, returning it to the environment for reuse in the food chain.
One of the challenges in defining death is in distinguishing it from life. Death would seem to refer to either the moment life ends, or when the state that follows life begins.[225] However, determining when death has occurred is difficult, as cessation of life functions is often not simultaneous across organ systems.[226] Such determination, therefore, requires drawing conceptual lines between life and death. This is problematic, however, because there is little consensus over how to define life. The nature of death has for millennia been a central concern of the world’s religious traditions and of philosophical inquiry. Many religions maintain faith in either a kind of afterlife or reincarnation for the soul, or resurrection of the body at a later date.[227]
Extinction
Extinction is the process by which a group of taxa or species dies out, reducing biodiversity.[228] The moment of extinction is generally considered the death of the last individual of that species. Because a species’ potential range may be very large, determining this moment is difficult, and is usually done retrospectively after a period of apparent absence. Species become extinct when they are no longer able to survive in changing habitat or against superior competition. Over 99% of all the species that have ever lived are now extinct.[229][117][118][119] Mass extinctions may have accelerated evolution by providing opportunities for new groups of organisms to diversify.[230]
Fossils
Fossils are the preserved remains or traces of animals, plants, and other organisms from the remote past. The totality of fossils, both discovered and undiscovered, and their placement in fossil-containing rock formations and sedimentary layers (strata) is known as the fossil record. A preserved specimen is called a fossil if it is older than the arbitrary date of 10,000 years ago.[231] Hence, fossils range in age from the youngest at the start of the Holocene Epoch to the oldest from the Archaean Eon, up to 3.4 billion years old.[232][233]
See also
- Biology, the study of life
- Astrobiology
- Biosignature
- History of life
- Lists of organisms by population
- Phylogenetics
- Viable system theory
- Central dogma of molecular biology
- Epigenetics
- Synthetic biology
- Hypothetical types of biochemistry
- Carbon-based life
Notes
- ^ The «evolution» and classification of viruses and other similar forms is still uncertain. Therefore, this listing may be paraphyletic if cellular life evolved from non-cellular life, or polyphyletic if the most recent common ancestor were not included.
- ^ Infectious protein molecules prions are not considered living organisms, but can be described as «organism-comparable organic structures».
- ^ Certain specific organism-comparable organic structures may be considered subviral agents, including virus-dependent entities: satellites and defective interfering particles, both of which require another virus for their replication.
- ^ Viruses are strongly believed not to descend from a common ancestor, with each realm corresponding to separate instances of virus coming into existence.[1]
- ^ To a first approximation this means that the enzymes needed for the system to function must be products of the system itself.
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Further reading
- Walker, Martin G. (2006). LIFE! Why We Exist … And What We Must Do to Survive. Dog Ear Publishing. ISBN 978-1-59858-243-7. Archived from the original on 24 July 2011.
External links
Wikiquote has quotations related to Life.
Look up life or living in Wiktionary, the free dictionary.
- Life (Systema Naturae 2000)
- Vitae (BioLib)
- Biota (Taxonomicon)
- Wikispecies – a free directory of life
- Resources for life in the Solar System and in galaxy, and the potential scope of life in the cosmological future
- «The Adjacent Possible: A Talk with Stuart Kauffman»
- Stanford Encyclopedia of Philosophy entry
- The Kingdoms of Life
by Brian Shilhavy
Life. It is one of the most common words in the English language. It is something to “live,” something to “spend,” something that begins and ends, something that is evaluated as “good” or “bad,” as “healthy” or “unhealthy.”
But how do we actually define it? Is it defined by our culture, or does it have an intrinsic meaning that transcends how the culture uses the word?
How you understand or define “life” affects pretty much everything you do, and I doubt that very many people have actually spent time evaluating their understanding of “life,” but passively just accept how the culture defines it.
“Life” is closely associated with “truth,” which means that the meaning of “life” is not dependent on people’s opinions or understanding of what it is.
It just is. It transcends even language, therefore it requires that we examine the language we use to describe and define life, and the closer we can come to its actual intrinsic meaning, the closer we come to understanding “truth.”
To help you decide whether or not you want to continue reading this article, I need to repeat my working premises that I have publicly explained in previous articles, and which are the premises I have accepted as true and are the foundation for all the articles I have personally written and published on Health Impact News for the past 12 years, which is that the Ancient writings of the Bible, also referred to as the “Scriptures,” are true in so much as they contain truth.
They are not the total embodiment of truth, as that originates from God (Yahweh/Jehovah) and his Son Jesus Christ, who is the “living Word of God.”
So for example, one of the “truths” found in the Scriptures is: Love your neighbor as yourself. This is written in English, so to properly understand this truth, we need to define “love” and “neighbor,” which is generally defined by our culture and language. It is also an “imperative” (command) truth.
But even if we come to an agreement on how these English words are defined so that we can properly communicate with each other about this truth so that we generally agree on how these words/concepts are defined, the truth of how that works out in your life, or mine, is not something we can find in the Scriptures.
Who I am supposed to be loving as my neighbor, will not usually be the same as who you are supposed to be loving as your neighbor, especially if we do not even know each other.
The general principle of this truth, “love your neighbor as yourself,” is always true, but how that truth is applied to someone’s life or situation is not the same for everyone.
And the knowledge of that kind of truth does not come from words written in a book, even if those words are true. They come from a relationship with the Living Word of God.
But that’s a topic for another article.
Where does Life Come From?
This is a question that is easily answered in the Scriptures, but when we closely examine just what the English word “life” means, it actually becomes more complicated.
As I have stated in other articles I have written, I have been studying the Bible for over 40 years, and I start each day by reading it and studying it.
I recently was reading through Paul’s two letters to his young associate, Timothy, and I recently wrote an article on what I found to be the main truth in Paul’s second letter to Timothy, and how that truth can be applied to us today. See:
Has Everyone Left You Because You are not Ashamed to Speak the Truth? Stay the Course!
But I came across something Paul wrote towards the end of his first letter to Timothy that Paul mentioned as an “aside.” In other words, it was not the main point he was making, but he stated it as a generally accepted fact.
I command you before God, who gives life to all things, and before Christ Jesus, who before Pontius Pilate testified the good confession, that you keep the commandment without spot, blameless, until the appearing of our Lord Jesus Christ; which in its own times he will show, who is the blessed and only Ruler, the King of kings, and Lord of lords; who alone has immortality, dwelling in unapproachable light; whom no man has seen, nor can see: to whom be honor and eternal power. Amen. (1 Timothy 6:13-16)
The “aside” here is the text I highlighted “who gives life to all things.”
I jotted down a note about this verse, and I thought to myself, “This would be a good topic for an article.”
I am familiar with this statement, and it is stated in many other places in the Scriptures, so I thought it would be a quick and easy article to write.
But as I dug deeper into the Greek words that are used in the New Testament which we translate as “life,” I soon learned that I did not understand this concept nearly as much as I thought I did, and so even though this would have been the earlier article I would have published before the one on 2 Timothy, I have now spent very many hours and days studying “life” as it is defined in the Scriptures, and I almost abandoned writing this article, so deep is the topic, and so inadequate do I feel in even attempting to write this article.
So I will be the first one to admit that I still have more to learn, but so important is this topic of “life,” that I felt I had to share what I have learned so far, as we are in desperate need today to identify the truth in our culture, and identify the lies, and it begins, in my opinion, with the proper understanding of “life.”
But before I start in examining the Greek words used by the New Testament writers that are translated into our English Bibles as “life,” let me give you other passages that confirm the truth Paul expressed here: God gives life to all things.
One of the most comprehensive statements of this truth is in Paul’s letter to the Colossians where he explains that Jesus Christ, in his pre-incarnate state, which means before he took on human form and was born to the virgin Mary, was the one who created everything in the universe.
He is the image of the invisible God, the firstborn over all creation.
For by him all things were created: things in heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities; all things were created by him and for him. He is before all things, and in him all things hold together. (Colossians 1:15-17)
Here is the same truth again written in Paul’s first letter to the Corinthians:
For even if there are so-called gods, whether in heaven or on earth (as indeed there are many “gods” and many “lords”), yet for us there is but one God, the Father, from whom all things came and for whom we live; and there is but one Lord, Jesus Christ, through whom all things came and through whom we live. (1 Corinthians 8:5-6)
Here is the apostle John writing the same truth:
In the beginning was the Word, and the Word was with God, and the Word was God. He was with God in the beginning. Through him all things were made; without him nothing was made that has been made. In him was life, and that life was the light of men. (John 1:1-4)
Here is the same truth being stated in the book of Hebrews:
In the past God spoke to our forefathers through the prophets at many times and in various ways, but in these last days he has spoken to us by his Son, whom he appointed heir of all things, and through whom he made the universe.
The Son is the radiance of God’s glory and the exact representation of his being, sustaining all things by his powerful word. After he had provided purification for sins, he sat down at the right hand of the Majesty in heaven. (Hebrews 1:1-3)
I realize that the English word “life” is not in all of these verses, but I believe the truth that God gives life to all things is included in these passages as well.
Because God’s creative actions also include things that are not “alive,” such as the elements of the earth.
Genesis, the first book of the Bible, teaches us that God took some of these elements that we would not say were “alive” but then formed them into a living being, the first man.
The LORD God formed the man from the dust of the ground and breathed into his nostrils the breath of life, and the man became a living being. (Genesis 2:7)
So we can conclusively say that the Bible clearly teaches that ALL life comes from God, specifically from the person Jesus Christ. So now we just need to define what this “life” is.
What is “Life?”
The English noun life, and its corresponding verb, to live, along with other cognates of this word, such as alive, lively, lifeless, etc., have multiple meanings, and we generally understand the meaning the speaker or author is using by its context.
“Live,” for example, can be a noun or a verb based on usage. So “Live your life to its fullest” has a different meaning from “It’s being broadcast live,” for example. In written English we determine the meaning by context, but in spoken English the pronunciation is different based on usage, making it easier to distinguish.
This is true in Koine Greek also, but when we get to the usage of the English word life in the New Testament portion of the Bible, there is actually more than one word in the Greek that is translated into this single word in the English. And of those words in the Greek, which are mainly 3 different words, each of those words can have multiple meanings as well, based on the context in which it is being used, just like the English word group.
The primary 3 words in the Greek that are translated (sometimes) by the English word life, are ζωή (zóé), ψυχή (psuché), and βίος (bios).
Zóé and its cognates are by far the most common words translated to the English life, and it is found in all 27 books of the New Testament.
Psuché is the second most common, used hundreds of times including its cognates.
Bios is the least common (this actually surprised me), and is only used 11 times in the entire New Testament.
Zoe is almost always translated into the English word “life.” I surveyed a few English translations, and the only exception I found was in the older King James Version in Luke 16:25, where it is translated “lifetime,” which restricts its meaning to the duration of our physical lives in our natural body between our physical birth and our physical death.
Here is a verse where Jesus uses the word that seems to refer to our “life” between physical birth and physical death:
Then he said to them, “Watch out! Be on your guard against all kinds of greed; a man’s life does not consist in the abundance of his possessions.” (Luke 12:15)
Here is an example of Paul using it the same way:
If only for this life we have hope in Christ, we are to be pitied more than all men. (1 Corinthians 15:19)
As with the English word “life,” zoe has different variations of meanings, and besides “lifetime” can refer to the “natural life” that applies to humans, animals, and plants, but is also used with “eternal life” as exceeding the “life” of just our natural bodies, but including our “soul” and “spirit” which are not confined to just the existence of our physical bodies.
This concept of “eternal life” is, by far, the more common meaning found in the New Testament, referring to “life” as an eternal existence not confined to the duration of time we spend in our physical bodies. Some examples (note, in some of these verses the verb form, zao, is also being used):
“Then they will go away to eternal punishment, but the righteous to eternal life.” (Matthew 25:46)
Just as Moses lifted up the snake in the desert, so the Son of Man must be lifted up, that everyone who believes in him may have eternal life. For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life. (John 3:14-16)
Jesus answered, “Everyone who drinks this water will be thirsty again, but whoever drinks the water I give him will never thirst. Indeed, the water I give him will become in him a spring of water welling up to eternal life.” (John 4:13-14)
“I tell you the truth, whoever hears my word and believes him who sent me has eternal life and will not be condemned; he has crossed over from death to life. I tell you the truth, a time is coming and has now come when the dead will hear the voice of the Son of God and those who hear will live. For as the Father has life in himself, so he has granted the Son to have life in himself. (John 5:24-26)
In the context of the New Testament writings, zoe also is used with “new life” to describe the spiritual rebirth found only in Jesus Christ, the first man resurrected from the (physical) dead which added new meaning to zoe that the ancient Greek philosophers writing in Classical Greek, such as Plato and Aristotle, did not have.
Jesus said to them, “I tell you the truth, it is not Moses who has given you the bread from heaven, but it is my Father who gives you the true bread from heaven. For the bread of God is he who comes down from heaven and gives life to the world.” “Sir,” they said, “from now on give us this bread.” Then Jesus declared, “I am the bread of life. He who comes to me will never go hungry, and he who believes in me will never be thirsty. (John 6:32-35)
Jesus said to her, “I am the resurrection and the life. He who believes in me will live, even though he dies; and whoever lives and believes in me will never die. Do you believe this?” (John 11:25-26)
We always carry around in our body the death of Jesus, so that the life of Jesus may also be revealed in our body. For we who are alive are always being given over to death for Jesus’ sake, so that his life may be revealed in our mortal body. (2 Corinthians 4:10-11)
For while we are in this tent, we groan and are burdened, because we do not wish to be unclothed but to be clothed with our heavenly dwelling, so that what is mortal may be swallowed up by life. (2 Corinthians 5:4)
The quality of this “life” is often associated with “light” and “truth” shining into the domain of Satan, exposing his lies hidden in the dark.
In the beginning was the Word, and the Word was with God, and the Word was God. He was with God in the beginning. Through him all things were made; without him nothing was made that has been made. In him was life, and that life was the light of men. The light shines in the darkness, but the darkness has not understood it. (John 1:1-5)
When Jesus spoke again to the people, he said, “I am the light of the world. Whoever follows me will never walk in darkness, but will have the light of life.” (John 8:12)
Psuché, on the other hand, is translated into English as “soul” about as often as it is translated into English as “life,” and refers to more than just our physical bodies. This Greek word is behind our modern English words like psyche, psychology, etc.
Here are some of the verses where psuche is translated as either “life” or “soul” in English:
Therefore I tell you, do not worry about your life, what you will eat or drink; or about your body, what you will wear. Is not life more important than food, and the body more important than clothes? (Matthew 6:25)
Then Jesus asked them, “Which is lawful on the Sabbath: to do good or to do evil, to save life or to kill?” But they remained silent. (Mark 3:4)
Do not be afraid of those who kill the body but cannot kill the soul. Rather, be afraid of the One who can destroy both soul and body in hell. (Matthew 10:28)
Take my yoke upon you and learn from me, for I am gentle and humble in heart, and you will find rest for your souls. (Matthew 11:29)
Here the same word is translated “life” in one verse, and then the exact same word (psuche) in the following verse is translated “soul”:
For whoever wants to save his life will lose it, but whoever loses his life for me will find it. What good will it be for a man if he gains the whole world, yet forfeits his soul? Or what can a man give in exchange for his soul? (Matthew 16:25-26)
Another word used in English to translate psuche sometimes is “mind.”
But the Jews who refused to believe stirred up the Gentiles and poisoned their minds against the brothers. (Acts 14:2)
In some verses, psuche is translated into the English word “heart.”
Obey them not only to win their favor when their eye is on you, but like slaves of Christ, doing the will of God from your heart. (Ephesians 6:6)
Consider him who endured such opposition from sinful men, so that you will not grow weary and lose heart. (Hebrews 12:3)
As should be obvious from just this brief look at the various uses of the two most common Greek words in the New Testament portion of the Bible that are translated into the English word “life,” it has a much broader meaning than its usage in modern Western culture today, which over-emphasizes only our physical life starting with physical birth and ending with physical death.
In the New Testament writings, “life” cannot be understood apart from Jesus Christ, who broke the power of physical death and instituted “eternal life” in heaven, the Kingdom of God, which also exists on the physical earth at this time in the spiritual realm, invading the Kingdom of Satan, the current world system, also referred to as “darkness.”
So using zoe, we come back to that famous statement made by Jesus Christ in John 14:6:
Jesus answered, “I am the way and the truth and the life. No one comes to the Father except through me.” (John 14:6)
Jesus did not just explain what “life” is, he claimed that he IS “life.” And this truth fits with what was written in the passage in Colossians I quoted above:
For by him all things were created: things in heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities; all things were created by him and for him. He is before all things, and in him all things hold together.
And he is the head of the body, the assembly; he is the beginning and the firstborn from among the dead, so that in everything he might have the supremacy.
For God was pleased to have all his fullness dwell in him, and through him to reconcile to himself all things, whether things on earth or things in heaven, by making peace through his blood, shed on the cross. (Colossians 1:16-20)
Jesus also used an analogy of a vine, a living plant, and the “branches” that lived off of the vine, but which “died” and were burned up once they were cut off from the vine, to illustrate how he IS the “life”:
I am the true vine, and my Father is the gardener. He cuts off every branch in me that bears no fruit, while every branch that does bear fruit he prunes so that it will be even more fruitful.
You are already clean because of the word I have spoken to you. Remain in me, and I will remain in you. No branch can bear fruit by itself; it must remain in the vine.
Neither can you bear fruit unless you remain in me. I am the vine; you are the branches. If a man remains in me and I in him, he will bear much fruit; apart from me you can do nothing.
If anyone does not remain in me, he is like a branch that is thrown away and withers; such branches are picked up, thrown into the fire and burned. (John 15:1-6)
Bios
Karl Marx (left) and Karl Ritter (right). These two men are credited with developing modern day academic and political theories that shaped the development of western culture.
But there is a 3rd Greek word that is sometimes translated “life” in the English translations of the Bible: bios. This noun is only used 11 times in the New Testament, and once in its verb form.
Notice how it is translated into English in each of these verses.
And he called his disciples to him and said to them, “Truly, I say to you, this poor widow has put in more than all those who are contributing to the offering box. For they all contributed out of their abundance, but she out of her poverty has put in everything she had, all she had to live on.” (Mark 12:43-44)
And as for what fell among the thorns, they are those who hear, but as they go on their way they are choked by the cares and riches and pleasures of life, and their fruit does not mature. (Luke 8:14)
And there was a woman who had had a discharge of blood for twelve years, and though she had spent all her living on physicians, she could not be healed by anyone. (Luke 8:43)
And the younger of them said to his father, ‘Father, give me the share of property that is coming to me.’ And he divided his property between them. (Luke 15:12)
But when this son of yours came, who has devoured your property with prostitutes, you killed the fattened calf for him!’ (Luke 15:30)
No soldier gets entangled in civilian pursuits, since his aim is to please the one who enlisted him. (2 Timothy 2:4 – note: some English translations say “every day life” or “affairs of life” for “bios” here.)
1 Peter 4:2-3 uses the verb form (only occurrence in the New Testament) in verse 2, and the noun in verse 3.
that you no longer should live the rest of your time in the flesh for the lusts of men, but for the will of God. For we have spent enough of our past time doing the desire of the Gentiles, and having walked in lewdness, lusts, drunken binges, orgies, carousings, and abominable idolatries. (1 Peter 4:2-3)
For all that is in the world, the lust of the flesh, the lust of the eyes, and the pride of life, isn’t the Father’s, but is the world’s. (1 John 2:16)
But whoever has the world’s goods, and sees his brother in need, and closes his heart of compassion against him, how does God’s love remain in him? (1 John 3:17)
I think it is easy to see by observing how bios is used in these verses that this is a very different, and mostly negative, term that is sometimes translated into “life” in English.
It is obviously only dealing with physical life, and the duration of that life between our physical birth and our physical death. It includes the things that “empower” our physical life, such as finances and worldly possessions, but also the emotions and desires that are tied into the physical world and the current world system ruled by Satan, such as pride, lust, idolatry, etc.
So even though bios is the original Greek word used the least amount of time in the New Testament, is it any surprise that of the three Greek words used to translate into “life,” that bios is the one most often used today in English and Western Culture?
We are familiar with the common English words derived from bios, such as biology, biologist, etc., which are used in academic settings in the study of “life.”
The English word “life” comes originally from the Germanic languages, the language group from where English originated.
Old English life (dative lif) “animated corporeal existence; lifetime, period between birth and death; the history of an individual from birth to death, written account of a person’s life; way of life (good or bad); condition of being a living thing, opposite of death; spiritual existence imparted by God, through Christ, to the believer,” from Proto-Germanic *leiban (source also of Old Norse lif “life, body,” Old Frisian, Old Saxon lif “life, person, body,” Dutch lijf “body,” Old High German lib “life,” German Leib “body”), properly “continuance, perseverance,” from PIE root *leip- “to stick, adhere.” (Source.)
“Biology,” on the other hand, appears to be an introduced word, both into German, as well as into French (a Latin language), in the late 1700s or early 1800s.
Here is the entry from etymonline.com:
biology (n.)
“the science of life and living things,” 1819, from Greek bios “life, one’s life, lifetime” (from PIE root *gwei- “to live;” see bio-) + -logy “study of.” Suggested 1802 by German naturalist Gottfried Reinhold Treviranus, and introduced as a scientific term that year in French by Lamarck; they seem to have hit upon the word independently.
They “seem to have hit upon the word independently“? Yeah, I don’t think so….
Merriam Webster, which today is owned by a Jewish financier in Switzerland, states:
First Known Use of biology
1799, in the meaning defined at sense 1
History and Etymology for biology
German Biologie, from bi- + -logie -logy
From Dictionary.com:
ORIGIN OF BIOLOGY
From the German word Biologie, dating back to 1805–15.
What they seem to agree upon is that the word we know today as “biology” was an introduced word from the early 1800s coming to use in the English from the German.
So what all was going on in Germany and Europe during this time period?
This was the period of history often referred to as the “Great Awakening” in Europe.
We have the rise of the House of Rothschild, for example, taking over the banking industry. We have the secret societies like the Freemason lodges, and the Illuminati, all taking form in Europe during this time, and influencing academics.
The theories of Marxism were written by Karl Marx and the theories of race development and the “Aryan Race” was written by Karl Ritter, and these two opposing theories would shape political and academic thought that shaped Western Culture in Europe, and was exported to the United States.
There were some positive influences also from the “Reformation Movement” during that time that at least worked at translating the Scriptures into the vernacular of the languages of the working classes.
Charles Darwin’s statue outside the library, formerly Shrewsbury School which he attended from 1818 to 1825. Source.
But the biggest development from this time period, by far, which gave birth to “biology,” was Charles Darwin, and this theories of “evolution.”
Here is the entry on “biology” from encyclopedia.com:
BIOLOGY.
Biology comes from the Greek word for life, bis, and the Greek word for thought or reasoning, logos. It denotes the science that studies life, the properties and processes that sustain life, the evolutionary history of life, and particular living organisms. It is a science of enormous diversity, breadth, and heterogeneity unified only by the conceptual framework provided by the theory of evolution.
Indeed, as famously noted in 1973 by the Russian evolutionary geneticist Theodosius Dobzhansky (1900–1975), “Nothing in biology makes sense except in the light of evolution”—a quote now replicated in so many university-level textbooks that it is almost a dictum in modern biology.
During this time period the definition of “science” began to evolve from a meaning that historically was synonymous with “knowledge” and “philosophy” and began to limit its study to strictly the bios of life, concerning only the physical life between our physical birth and physical death, and all the elements of Satan’s world system such as pride, lust, greed, etc., and eliminate all other meanings of “life” as “unscientific.”
Today, in American academics, you are generally not allowed to challenge Darwin’s theories of evolution, theories which have undergone many changes over the years, as it is presented as a scientific “fact,” even though it is only a theory which is really not supported by science at all.
The actual science that Darwin (and others) observed were primarily species adapting to their environment, in order to survive, and not evolving into a higher life form which in this theory takes BILLIONS of years to happen, and could never be observed by science, but just accepted by faith.
What we have completely lost in modern day academics, is the teaching that life comes from our Creator, and our Savior, Jesus Christ. And along with this view of “life,” is a declining emphasis on the humanities and arts, the creative expression of human life, as “science” is now regulated to only physical science, based mainly on Darwinian Biology, which, among other things, has given us modern medicine and the pharmaceutical industry with its very narrow, and very evil, view of “life” that came from bios.
Transhumanism’s False Claims
I have wanted to write an article for some time now debunking all the false claims for “transhumanism.” But as I began to study the language used to define and describe “life,” I quickly realized that the easiest way to debunk transhumanism is to first properly define “life.”
Once we realize what life really is, we can easily see that the promises, or warnings, depending on who you are reading or listening to, regarding transhumanism are all based on a false definition of “life”.
Transhumanism is nothing more than the 21st Century version of Darwinian biology, based on bios, instead of zoe and psuche. Modern academic teaching has turned the meaning of life upside down, putting the lowest forms of “life” that deal only with physical life and the elements of this world system on top, and eliminating the human soul and spirit completely.
If you want to live your life like that, ignoring your soul and your spirit, go ahead. You will fit into modern society just fine, along with the modern belief in the religious cult of “medicine” and their priests called “doctors.”
This false belief that originates with the Greek concept of bios, and popularized and institutionalized with academic thought built upon “biology,” is what produced the false science known today as “genetics,” which was originally called “eugenics,” until it was associated with Nazi Germany and Hitler and perceived as negative.
Therefore it was rebranded as “genetics,” and it is what fuels most “scientific” research today that gives us modern day drugs and vaccines, which never promote a healthy life, but merely manage disease at best, or kills life prematurely at its worst. For more information on this topic, see our previous articles:
Mapping the Genome and Modern Genetics: Eugenics Repackaged for Modern Times
Eugenics in the United States Today: Are We on the Same Path Nazi Germany Followed?
Dr. David Martin Exposes the False Foundation of Eugenics: “You Don’t Have DNA”
To understand the false science of “genetics” and “biology,” you first need to understand what true “life” really is, which includes your eternal soul and your spirit.
All life originates from God, through Jesus Christ. I quoted these verses above, and the Greek word for “all” is pas, which really means ALL, or the WHOLE.
That means neither man, nor Satan, can create life. Period. End of story.
They can affect our physical bodies and the bios that we live from physical birth to physical death, but neither man nor Satan has control of our soul or spirit.
Do not be afraid of those who kill the body but cannot kill the soul. Rather, be afraid of the One who can destroy both soul and body in hell. (Matthew 10:28)
We are created in the image of God, and nothing can change that, because all life originates and is upheld by God through Jesus Christ. There are no exceptions, according to the language used in the Scriptures.
What about procreation? Cannot a man and women create children through sex?
No!
We just established the fact that all life is created by God. When a man and women join together and produce a child, they are participating in the creative process with God, but they are not creating anything. God created the sperm, and the egg.
Every single person born from their mother was created by God.
For you created my inmost being; you knit me together in my mother’s womb.
I praise you because I am fearfully and wonderfully made; your works are wonderful, I know that full well.
My frame was not hidden from you when I was made in the secret place. When I was woven together in the depths of the earth, your eyes saw my unformed body.
All the days ordained for me were written in your book before one of them came to be. (Psalms 139:13-16)
If a man and a women do not have the power to create a human being, therefore, then Satan and his demons most certainly cannot create “transhumans”!! And neither can the technocrats.
I am currently seeing two forms of transhumanism being discussed in the popular culture and also in the Alternative Media.
One is put forward by the technocrats such as those who work with the World Economic Forum and have defined what they want to do with “transhumanism.”
The second is promoted mostly by Evangelical Zionist Christians who believe that Satan can procreate and produce hybrid demons/humans, and much of this is based on the Book of Enoch, which was rejected as an authentic piece of literature to be included in the Bible.
And as I have shown here in this article, probably the main reason why the Book of Enoch was not included in the Bible is that it has a false definition of “life.” The Biblical definition of “life” sees ALL life as originating with God, and even being upheld in the universe today by God.
The writers of the New Testament dealt very strongly with the issues taught in the Book of Enoch, which deal with “bloodlines” or genealogies and hybrid demon-human beings. Here are a few of the warnings from Paul to NOT get involved with these debates and arguments:
As I urged you when I went into Macedonia, stay there in Ephesus so that you may command certain men not to teach false doctrines any longer nor to devote themselves to myths and endless genealogies. These promote controversies rather than God’s work–which is by faith. The goal of this command is love, which comes from a pure heart and a good conscience and a sincere faith. Some have wandered away from these and turned to meaningless talk. (1 Timothy 1:3-6)
Therefore, rebuke them sharply, so that they will be sound in the faith and will pay no attention to Jewish myths or to the commands of those who reject the truth. To the pure, all things are pure, but to those who are corrupted and do not believe, nothing is pure. In fact, both their minds and consciences are corrupted. (Titus 1:13-15)
But avoid foolish controversies and genealogies and arguments and quarrels about the law, because these are unprofitable and useless. (Titus 3:9)
As far as the false claims of the technocrats, no machine, robot, or artificial intelligence can ever be defined as “life.” It is also based on the false science of “genetics,” and it is all cow dung.
These are the false prophets of our day. The Christian false prophets are terrorizing people who foolishly took a COVID-19 injection by telling them that they now cannot be healed or saved, and that their DNA has been altered and they are no longer human.
They say these things because they have a false understanding of “life,” and there is no room for God in their thinking to overcome the negative effects of the pharmaceutical cult. They need to repent.
The technocrats are from my generation, and they grew up watching Star Trek and Star Wars and actually believing all that science fiction, because they too have a false concept of “life.” They are actually not even very smart people, most of them, and as soon as their technology developed to the point where almost everyone started using it, the Globalists came in and bought them all, as they sold their souls to the Wall Street Bankers and Billionaires.
But transhumanism is only science fiction, and it always will be. AI, robots, etc. are all creations of man, corrupted by Satan, and cannot create life, nor be called “life.”
It is mainly a distraction to the real dangers of technology, and things like artificial intelligence, which is massive data processing that allows new levels of tracking and surveillance that we have never seen before.
It is one thing to spy on every single person on the planet through technology, and it is another thing to be able to process all that data and use it for evil purposes, and that is the true danger of the technocrats who are now owned by the Wall Street bankers.
But here is the truth:
Jesus answered, “I am the way and the truth and the life. No one comes to the Father except through me.” (John 14:6)
End of story.
Jesus controls life, and if we know him and have his Spirit living inside of us, we have absolutely nothing to fear, because the worst thing our enemy can do to us is kill our bios, our physical life, which is going to pass away at some point anyway, as our soul lives on into eternity without the physical body.
I declare to you, brothers, that flesh and blood cannot inherit the kingdom of God, nor does the perishable inherit the imperishable.
Listen, I tell you a mystery: We will not all sleep, but we will all be changed–in a flash, in the twinkling of an eye, at the last trumpet.
For the trumpet will sound, the dead will be raised imperishable, and we will be changed. For the perishable must clothe itself with the imperishable, and the mortal with immortality.
When the perishable has been clothed with the imperishable, and the mortal with immortality, then the saying that is written will come true: “Death has been swallowed up in victory.”
“Where, O death, is your victory? Where, O death, is your sting?” The sting of death is sin, and the power of sin is the law.
But thanks be to God! He gives us the victory through our Lord Jesus Christ.
Therefore, my dear brothers, stand firm. Let nothing move you. Always give yourselves fully to the work of the Lord, because you know that your labor in the Lord is not in vain. (1 Corinthians 15:50-58)
Comment on this article at Created4Health.org
See Also:
Understand the Times We are Currently Living Through
The God of All Comfort
Year 2023: Will America Fulfill Its Destiny? Jesus Christ is the Only “Transhuman” the World Has Ever Seen or Will Ever See
An Invitation to the Technologists to Join the Winning Side
Synagogue of Satan: Why It’s Time to Leave the Corporate Christian Church
How to Determine if you are a Disciple of Jesus Christ or Not
Epigenetics Exposes Darwinian Biology as a Religion – Your DNA Does NOT Determine Your Health!
What Happens When a Holy and Righteous God Gets Angry? Lessons from History and the Prophet Jeremiah
Insider Exposes Freemasonry as the World’s Oldest Secret Religion and the Luciferian Plans for The New World Order
Identifying the Luciferian Globalists Implementing the New World Order – Who are the “Jews”?
Published on January 23, 2022
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See synonyms for: life / lives on Thesaurus.com
This shows grade level based on the word’s complexity.
noun, plural lives [lahyvz]. /laɪvz/.
the condition that distinguishes organisms from inorganic objects and dead organisms, being manifested by growth through metabolism, reproduction, and the power of adaptation to environment through changes originating internally.
the sum of the distinguishing phenomena of organisms, especially metabolism, growth, reproduction, and adaptation to environment.
the animate existence or period of animate existence of an individual: to risk one’s life; a short life and a merry one.
a corresponding state, existence, or principle of existence conceived of as belonging to the soul: eternal life.
the general or universal condition of human existence: Too bad, but life is like that.
any specified period of animate existence: a man in middle life.
the period of existence, activity, or effectiveness of something inanimate, as a machine, lease, or play: The life of the car may be ten years.
a living being, especially a human being: Several lives were lost.
living things collectively: the hope of discovering life on other planets; insect life.
a particular aspect of existence: He enjoys an active physical life.
the course of existence or sum of experiences and actions that constitute a person’s existence: His business has been his entire life.
a biography: a newly published life of Willa Cather.
animation; liveliness; spirit: a speech full of life.
resilience; elasticity.
the force that makes or keeps something alive; the vivifying or quickening principle: The life of the treaty has been an increase of mutual understanding and respect.
a mode or manner of existence, as in the world of affairs or society: So far her business life has not overlapped her social life.
the period or extent of authority, popularity, approval, etc.: the life of the committee; the life of a bestseller.
a prison sentence covering the remaining portion of the offender’s animate existence: The judge gave him life.
anything or anyone considered to be as precious as life: She was his life.
a person or thing that enlivens, cheers, or brightens a gathering or group: the life of the party.
effervescence or sparkle, as of wines.
pungency or strong, sharp flavor, as of substances when fresh or in good condition.
nature or any of the forms of nature as the model or subject of a work of art: drawn from life.
Baseball. another opportunity given to a batter to bat because of a misplay by a fielder.
(in English pool) one of a limited number of shots allowed a player: Each pool player has three lives at the beginning of the game.
adjective
for or lasting a lifetime; lifelong: a life membership in a club; life imprisonment.
of or relating to animate existence: the life force; life functions.
working from nature or using a living model: a life drawing; a life class in oil painting.
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Idioms about life
- to recover consciousness.
- to become animated and vigorous: The evening passed, but somehow the party never came to life.
- to appear lifelike: The characters of the novel came to life on the screen.
as large as life, actually; indeed: There he stood, as large as life.Also as big as life .
come to life,
for dear life, with desperate effort, energy, or speed: We ran for dear life, with the dogs at our heels.Also for one’s life .
for the life of one, as hard as one tries; even with the utmost effort: He can’t understand it for the life of him.
get a life, to improve the quality of one’s social and professional life: often used in the imperative to express impatience with someone’s behavior: Stop wasting time with that nonsense; get a life!
not on your life, Informal. absolutely not; under no circumstances; by no means: Will I stand for such a thing? Not on your life!
take one’s life in one’s hands, to risk death knowingly: We were warned that we were taking our lives in our hands by going through that swampy area.
to the life, in perfect imitation; exactly: The portrait characterized him to the life.
Origin of life
before 900; Middle English lif(e); Old English līf; cognate with Dutch lijf,German Leib body, Old Norse līf life, body; akin to live1
OTHER WORDS FROM life
pre·life, adjectiveun·der·life, noun
Words nearby life
lieve, Lièvre, lie with, LIF, Lifar, life, life-and-death, life annuity, life arrow, life assurance, life belt
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Words related to life
activity, growth, heart, soul, career, course, generation, history, season, survival, time, body, existence, living, man, person, woman, autobiography, journal, memoir
How to use life in a sentence
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Despite his condition, Paul maintained his social life to stave off the depression.
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Wenstrup also focused on Biden and Harris, accusing the Democrats of “playing politics with people’s lives” without responding to the reporter’s question.
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Multiply that by an expected life span of at least ten years.
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Look, you’re, you’ve spent your whole life in public service.
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“We’ve spent $8 trillion and we’ve lost thousands of lives but really millions of lives because I view both sides.”
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His life as a man is built around health insurance and tax services.
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It was also an attack on our freedom of expression and way of life.
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I always wanted my life to be that way, and it became that way.
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I liked it because it was like my life coming back together.
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When the father arrived at the hospital, he was told that Andrew Dossi was in surgery, but the wounds were not life-threatening.
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Now, it immediately occurred to Davy that he had never in his whole life had all the plums he wanted at any one time.
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Dean Swift was indeed a misanthrope by theory, however he may have made exception to private life.
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We shall recover again some or all of the steadfastness and dignity of the old religious life.
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It is the dramatic impulse of childhood endeavouring to bring life into the dulness of the serious hours.
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Woman is mistress of the art of completely embittering the life of the person on whom she depends.
British Dictionary definitions for life
noun plural lives (laɪvz)
the state or quality that distinguishes living beings or organisms from dead ones and from inorganic matter, characterized chiefly by metabolism, growth, and the ability to reproduce and respond to stimuliRelated adjectives: animate, vital
the period between birth and death
a living person or beingto save a life
the time between birth and the present time
- the remainder or extent of one’s life
- (as modifier)a life sentence; life membership; life subscription; life work
the amount of time that something is active or functioningthe life of a battery
a present condition, state, or mode of existencemy life is very dull here
- a biography
- (as modifier)a life story
- a characteristic state or mode of existencetown life
- (as modifier)life style
the sum or course of human events and activities
liveliness or high spiritsfull of life
a source of strength, animation, or vitalityhe was the life of the show
all living things, taken as a wholethere is no life on Mars; plant life
sparkle, as of wines
strong or high flavour, as of fresh food
(modifier) arts drawn or taken from a living modellife drawing; a life mask
physics another name for lifetime
(in certain games) one of a number of opportunities of participation
as large as life informal real and living
larger than life in an exaggerated form
come to life
- to become animate or conscious
- to be realistically portrayed or represented
for dear life urgently or with extreme vigour or desperation
for the life of one though trying desperately
go for your life Australian and NZ informal an expression of encouragement
a matter of life and death a matter of extreme urgency
not on your life informal certainly not
the life and soul informal a person regarded as the main source of merriment and livelinessthe life and soul of the party
the life of Riley informal an easy life
to the life (of a copy or image) resembling the original exactly
to save one’s life informal in spite of all considerations or attemptshe couldn’t play football to save his life
the time of one’s life a memorably enjoyable time
true to life faithful to reality
Word Origin for life
Old English līf; related to Old High German lib, Old Norse līf life, body
Collins English Dictionary — Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for life
The properties or qualities that distinguish living plants and organisms from dead or inanimate matter, including the capacity to grow, metabolize nutrients, respond to stimuli, reproduce, and adapt to the environment. The definitive beginning and end of human life are complex concepts informed by medical, legal, sociological, and religious considerations.
Living organisms considered as a group, such as the plants or animals of a given region.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Other Idioms and Phrases with life
In addition to the idioms beginning with life
- life and death
- life is too short
- life of Riley
- life of the party
also see:
- bet one’s ass (life)
- big as life
- breathe new life into
- bring to life
- change of life
- charmed life
- come alive (to life)
- dog’s life
- facts of life
- for dear life
- for the life of
- get a life
- good life
- late in life
- lay down (one’s life)
- lead a double life
- matter of life and death
- new lease on life
- not on your life
- of one’s life
- once in a lifetime
- prime of life
- risk life and limb
- run for it (one’s life)
- staff of life
- story of my life
- take someone’s life
- to save one’s life
- to the life
- true to (life)
- variety is the spice of life
- walk of life
- while there’s life there’s hope
- you bet (your life)
The American Heritage® Idioms Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
As ‘nightmare’ scenario unfolds in one plant, auto union fights for ‘American way of life‘ yahooBuzzArticleHeadline = ‘As ‘nightmare’ scenario unfolds in one plant, auto union fights for ‘American way of life »; yahooBuzzArticleSummary = ‘Article: As bargaining for a new contract begins, GM, Ford and Chrysler will push autoworkers for wage and benefit concessions. ❋ Unknown (2007)
This is your life flashing before your eyes, this is your ~life~ passing you by. ❋ Wendchymes (2007)
This literature tends to show subjects ‘self-ratings of well-being or happiness are based partly on pleasure, partly on the absence of negative affect, and partly on their views of how well they are achieving the ends they regard as important in life (their ˜life satisfaction™). ❋ Katz, Leonard D. (2006)
If what I have found so far and my search has not ended yet, nor will it ever likely is accurate- that life begins at fertilization both by the independent definition of life and a scientific understanding of the life cycle- then abortion must end. ❋ Unknown (2005)
He also credits Aristotle with saying: Teachers who educated children deserved more honour than parents who merely gave them birth; for bare life is furnished by the one, the other ensures a good life (p. 463). ❋ Unknown (1989)
_The girl must prepare for life work in the home, or life work outside the home, or a period of either followed by the other, or perhaps a combination of both during some part or even all of her mature life_. ❋ Marguerite Stockman Dickson (N/A)
Now those who regard literature as an important thing, playing a significant part in the life of a nation, must, as I have already indicated, seek in it something more positive than a _distraction_ from life; for them it must be an _addition to life_. ❋ Rolfe Arnold Scott-James (N/A)
Now, relying on these discoveries, as well as upon the successful demonstration, by inorganic means, of organic acids in chemistry, and starting from the supposition that the first appearance of life must necessarily be explained by those agencies which are already active in the inorganic nature, many scientists have attempted the so-called _mechanical explanation of life_. ❋ Rudolf Schmid (N/A)
There are, as I suppose, the following several kinds of life: (1) _Spirit life_; (2) _Moral life_; (3) _Electric life_. ❋ Daniel Clark (N/A)
In New York the frontier was just beyond the posts on the Hudson River; and in Virginia life outside of the oldest settlements was strictly «_life on the border_.» ❋ William Worthington Fowler (N/A)
_After the death_, &c. 172, l. 3. _or_ else it _should cost life for life_; and that in a short time they should be like hogs kept for slaughter, by this vitious ❋ John Knox (N/A)
Not enough that you would barter my life — yes, my _life_ — for gold, sell my heart’s blood for your own ease and comfort? ❋ Lawrence L. Lynch (N/A)
It appears to be the only kind of matter with which life is ever associated, and for this reason protoplasm is called the _physical basis of life_. ❋ Francis M. Walters (N/A)
By nature it is implanted in man that he should live in civil society, for since he cannot attain in solitude the necessary means of civilized life, it is a Divine provision that he comes into existence adapted for taking part in the union and assembling of men, both in the Family and in the State, which alone can supply adequate facilities for _the perfecting of life_. ❋ Various (N/A)
The life of the kings of Egypt, says Diodorus, was not like that of other monarchs who are irresponsible and may do just what they choose; on the contrary, everything was fixed for them by law, not only their official duties, but even the details of their daily life . ❋ Unknown (1922)
Private life, Weems avowed, is real life; and though, lacking first-hand knowledge, he was obliged to invent, he seemed intimate and credible to an audience somewhat overwhelmed by the heavy splendor of the more official orations and odes and sermons called forth by Washingtons death. ❋ Unknown (1921)
As Platonism began with the ideal of the good or the object of life, so the new idealism begins with the conviction of duty, or _the story of life_. ❋ Ralph Barton Perry (1916)
NATURAL phenomenon of human life brings us to the scientifical source of ethics and I prove that the so-called “highest ideals of humanity” have nothing of “sentimentalism” or of the “_super_natural” in them, but are exclusively the _fulfilment_ of the _natural laws_ for the _human class of life_. ❋ Alfred Korzybski (1914)
The true preacher can be known by this, that he deals out to the people his life, life passed through the fire of thought. ❋ Unknown (1909)
We may then take it, without prejudice to any special belief, that the spiritual life we wish to study is _one life_; based on experience of one Reality, and manifested in the diversity of gifts and graces which men have been willing to call true, holy, beautiful and good. ❋ Evelyn Underhill (1908)
❋ Anonymous (2003)
[Life’s a bitch], [and then] you [die]. ❋ Mr. Cynic (2005)
[Insert Name] is reading UrbanDictionary because it is the most intriguing activity that Insert Name could think of doing at the moment in his life.
([Sailor Jerry] [says hi]) ❋ Wittyname (2010)
At age 4, success is…not peeing [in your pants].
At age 12, success is…having friends.
At age 16, success is…having [a driver’s] [license].
At age 20, success is…having sex.
At age 35, success is…having money.
At age 50, success is…having money.
At age 60, success is…having sex.
At age 70, success is…having a driver’s license.
At age 75, success is…having friends.
At age 90, success is…not peeing in your pants. ❋ Ay Yo (2004)
god damn [eve] and her [fat ass] for eating [an apple], life is her fault. ❋ DoUNoTylrDurden (2005)
[My life] is rapidly becoming a [pun] for a seriously [disturbed] joke. ❋ Bulletproof Marshmallow (2003)
[Boy 1]: [how do] you think [your life] is?
Boy2: Shit ❋ Megumisgf (2022)
Don’t take life to seriously. [You’ll never] [get out of it] [alive] ❋ Garabaldi (2003)
[Life] is like [a dick], when it gets [hard fuck] it! ❋ I’ll Never Tell (2003)
life in the ’emergin’ [countries] ❋ Cordelia (2004)
Britannica Dictionary definition of LIFE
1
[noncount]
:
the ability to grow, change, etc., that separates plants and animals from things like water or rocks
-
He believes that God gives life to all creatures.
-
the miracle of life
-
eternal/everlasting life
2
a
:
the period of time when a person is alive
[noncount]
-
She knew what she wanted to do early in life. [=when she was young]
-
He became famous relatively late in life. [=at a relatively old age]
-
He became famous later in life. = He became famous in later life.
[count]
-
She was happy and healthy for most of her life.
-
The people in her family tend to have long/short lives.
-
I’ve known her all my life.
-
He is nearing the end of his life.
-
They spent their whole/entire lives in one town. = They lived in one town all their lives.
-
People can expect to change jobs several times in their life/lives.
-
They’ve been waiting their whole/entire life/lives for an opportunity like this.
-
This is the financial opportunity of his life. [=of his lifetime; the best chance in his life to make money]
b
:
the experience of being alive
[noncount]
-
What do you really want out of life?
-
He believes in living life to the fullest. [=in living a very full and rich life]
-
All this paperwork has made life much more difficult.
-
The details of everyday/ordinary life can be fascinating.
-
life in the city/country = city/country life
-
Sometimes life just isn’t fair.
-
We can laugh at things in movies that would scare us in real life. [=in a real situation; in actual existence]
-
Oh well, that’s life! [=bad things will happen, and you have to deal with them]
-
Despite the political upheaval, for most people life goes on as usual. [=the activities of life continue in the usual way]
[count]
-
What do you really want to do with your life?
-
Her children say that she has ruined their lives.
-
She talked about the men in her life. [=the men she has had a romantic or close relationship with during her life]
-
She has dedicated/devoted her life to helping other people.
-
All this paperwork has made my life much more difficult.
-
They’re trying to get/put their lives back together. [=to begin living in a normal way after suffering loss, hardship, etc.]
-
She was the love of my life. [=the person I loved more than any other person at any time in my life]
-
I’ve never heard such a silly idea in all my life! [=at any time] = Never in my life have I heard such a silly idea!
-
They’re old enough to run/live their own lives. [=to make their own decisions about how to live]
-
After all the problems they’ve had recently, they just want to get/move on with their lives. [=to continue living their lives in the usual way]
-
I’m not surprised that I didn’t get the job. That’s the story of my life. [=that’s the way things usually or always happen in my life]
— often used before another noun
-
She told us her life story. [=she told us about many of the things that had happened to her in her life]
-
a lack of life experience [=experience and knowledge gained through living]
◊ If your life flashes/passes before your eyes or if your life flashes/passes before you, many memories from different parts of your life quickly appear in your mind one after the other.
-
Her life flashed before her eyes when her car was about to crash.
3
[count]
a
:
a specified part of a person’s life
-
He talked about his life as an artist.
-
the social lives of college students
-
How’s your love/sex life?
-
They had difficult home lives when they were children.
-
They are trying to keep their personal/private lives separate from their public lives.
-
the responsibilities of their family life
b
:
a specified way or manner of living
-
He lived/led a life of crime. [=he was a criminal]
-
They have lived/led sheltered lives.
-
He is trying to make a better life for himself and his family.
◊ Your way of life is how you live your life.
-
a fisherman’s way of life
-
Most people don’t approve of my way of life.
-
a traditional way of life
4
[count]
:
the state or condition of being alive
-
They spared the horse’s life. [=they did not kill the horse]
-
She feels that her life is in danger. = She fears for her life. = She is in fear for her life. [=she feels that she is in danger of being killed]
-
She risked her life [=she did something very dangerous that could have resulted in her death] to help him.
-
She gave/sacrificed her life [=she did something that resulted in her death] for her country.
-
He was running for his life. [=he was running to escape from great danger]
-
He is fighting for his life. [=he is very sick or injured and may die]
-
A would-be assassin made an attempt on the President’s life. [=tried to kill the President]
5
[noncount]
:
living things of a specified kind or in a specified place
-
There may be a great deal of animal/plant life still to be discovered in this region.
-
forest life
-
ocean life
-
Will we ever find intelligent life on other planets?
6
:
the time when something can be used
:
the period when something exists or is useful or effective
[noncount]
-
battery life
-
the life of an insurance policy
-
They claim that using their product will extend the life of the car.
-
a warranty that is good for the life of the product
[count]
-
a product that extends the lives of the rugs/cars
—
see also half-life, shelf life
7
[noncount]
a
:
energy and spirit
-
eyes full of life
-
(informal) suck the life out of a room [=take all the fun and energy out of a group of people in a room]
b
:
activity and movement
-
The streets were humming with life. [=the streets were filled with people and activity]
-
There were no signs of life in the deserted village.
8
[count]
:
a book that tells about the life of a person
:
biography
-
She wrote a life of Napoleon.
-
Boswell’s Life of Johnson
9
[noncount]
:
the punishment of being kept in a prison for the rest of your life
:
life imprisonment
-
He was found guilty and sentenced to life. = (informal) He got life. = He was given life.
a life of its own
◊ Something that takes on a life of its own becomes very large, important, or hard to control.
-
The project soon took on a life of its own and prevented us from getting any other work done.
-
The story took on a life of its own and began to appear on news broadcasts everywhere.
all walks of life
or
every walk of life
—
see 2walk
a matter of life and death
:
something that is extremely important and often involves decisions that will determine whether someone lives or dies
-
Being prepared for severe weather can be a matter of life and death.
—
see also life-and-death
a new lease on/of life
—
see 1lease
(as) big as life
(US)
informal
or chiefly British
(as) large as life
:
in person
— used to describe the surprise of seeing someone
-
I never expected her to come to the party, but there she was, as big as life.
bet/stake your life on
◊ If you would bet/stake your life on something, you are very sure that it will happen.
-
“Will she keep her promise?” “I’d bet/stake my life on it!”
breathe (new) life into
:
to give new energy and excitement to (something)
-
She is credited with breathing new life into contemporary art.
-
The singer managed to breathe life into some tired old songs.
bring someone or something back to life
:
to cause someone or something that has died to begin living again
-
The story is about a mad scientist who tries to bring dead people back to life.
— often used figuratively
-
They’re trying to bring the restaurant back to life by introducing a new menu.
-
an old theory that is being brought back to life
bring something to life
:
to make something very interesting, appealing, or exciting
-
She brings history to life with her books.
come to life
1
:
to become very interesting, appealing, or exciting
-
The movie really comes to life when she appears on the screen.
2
of a place
:
to become filled with the energy and excitement of active people
-
Downtown comes to life each night when the clubs open.
3
of a machine
or
sputter/roar (etc.) to life
:
to begin working
-
The engine suddenly roared to life.
for dear life
:
very tightly or quickly because of fear or danger
-
He was hanging/holding on to the rope for dear life.
-
They were running for dear life to get away from the vicious dogs.
for life
:
for the whole of your life
:
for the rest of your life
-
They met in college and have remained friends for life.
-
He was sentenced to prison for life.
for the life of me
informal
:
in any way at all
— used to say that you are unable to remember or understand something
-
I couldn’t for the life of me remember what her name was.
-
For the life of me, I can’t think of any reasons why you wouldn’t want a computer at home.
frighten/scare the life out of
informal
:
to frighten (someone) very badly
-
You (nearly) scared the life out of me when you startled me like that!
from life
of a painting, drawing, etc.
:
from looking at an actual person, object, etc.
-
drawings done from life rather than from photographs
:
to stop spending time doing or thinking about things that are not important or interesting
:
to begin to have a more interesting or exciting life
-
My girlfriend’s parents are nice people, but all they do is watch TV all day. They need to get a life.
lay down your life
—
see lay down at 1lay
life depends on
◊ If your life depends on something, then you must do it.
-
His life depends on how he answers this question.
-
He was studying as if his life depended on it.
— often used in negative statements
-
I wouldn’t eat that food if my life depended on it. [=I would never eat it]
lose your life
:
to die
-
She nearly lost her life in a car accident.
-
Many lives were lost. [=many people died]
new life
◊ When something takes on (a) new life or when you give something new life or give new life to something, it becomes more active, interesting, etc.
-
Plain old mashed potatoes take on a new life in this recipe.
-
Falling interest rates gave new life to the housing market.
not on your life
informal
— used as a very forceful way of saying “no” or “never”
-
Do the government’s policies really help the average worker? Not on your life.
risk life and limb
:
to do something that is very dangerous
-
They risked life and limb to pull the child from the river.
save someone’s life
—
see 1save
take/claim someone’s life
:
to cause someone’s death
-
Two years ago he was diagnosed with the illness that eventually took his life.
-
The flood claimed many lives. [=caused the deaths of many people]
take your own life
:
to kill yourself
-
He threatened to take his own life [=commit suicide], but no one believed him.
the life of the party
(US)
or chiefly British
the life and soul of the party
:
someone who is very lively and amusing at a party or other social gathering
the light of your life
—
see 1light
the next life
or
the life to come
:
a life that is believed by some people to come after death
-
He believed that he would see his family again in the next life.
to save your life
—
see 1save
Britannica Dictionary definition of LIFE
always used before a noun
1
:
of or relating to life
-
the life force in all things
2
:
done as long as a person lives
:
existing or lasting throughout a person’s life
-
a life [=lifelong] member
-
my life savings [=all the money I have saved in my life]
-
He was given a life sentence in prison.