Editing Life (section)

=== Descriptive ===

{{further|Organism}}

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 implies all or most of the following traits:<ref name=McKay/><ref name=Koshland>{{Cite journal |title=The Seven Pillars of Life |journal=Science |date=22 March 2002 | first=Daniel E. Jr. | last=Koshland |volume=295 |issue=5563 |pages=2215–2216 |doi=10.1126/science.1068489 |pmid=11910092 |doi-access=free }}</ref><ref>{{Cite book |title=The American Heritage Dictionary of the English Language |publisher=Houghton Mifflin |year=2006 |isbn=978-0-618-70173-5 |edition=4th |chapter=life }}</ref><ref name=merriamwebster>{{cite web|url=http://www.merriam-webster.com/dictionary/life|title=Life|publisher=Merriam-Webster Dictionary|access-date=25 July 2022|url-status=live|archive-url=https://web.archive.org/web/20211213211541/https://www.merriam-webster.com/dictionary/life|archive-date=13 December 2021}}</ref><ref>{{cite web |url=http://phoenix.lpl.arizona.edu/mars141.php |title=Habitability and Biology: What are the Properties of Life? |access-date=6 June 2013 |website=Phoenix Mars Mission |publisher=The University of Arizona |url-status=live |archive-url=https://web.archive.org/web/20140416114923/http://phoenix.lpl.arizona.edu/mars141.php |archive-date=16 April 2014 }}</ref><ref name="JBS-2012Feb">{{cite journal |last=Trifonov |first=Edward N. |title=Definition of Life: Navigation through Uncertainties |journal=Journal of Biomolecular Structure & Dynamics |volume=29 |issue=4 |pages=647–650 |doi=10.1080/073911012010525017 |pmid=22208269 |year=2012 |s2cid=8616562 |doi-access=free }}</ref>

# [[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 [[cell (biology)|cells]]&nbsp;– the basic units of life.
# [[Metabolism]]: transformation of energy, used to convert chemicals into cellular components ([[anabolism]]) and to decompose organic matter ([[catabolism]]). Living things [[bioenergetics|require energy]] for homeostasis and other activities.
# [[Cell growth|Growth]]: maintenance of a higher rate of anabolism than catabolism. A growing organism increases in size and structure.
# [[Adaptation]]: the evolutionary process whereby an organism becomes better able to live in its [[habitat]].<ref>{{cite book |last=Dobzhansky |first=Theodosius |author-link=Theodosius Dobzhansky |chapter=On Some Fundamental Concepts of Darwinian Biology |date=1968 |chapter-url=http://dx.doi.org/10.1007/978-1-4684-8094-8_1 |title=Evolutionary Biology |pages=1–34 |place=Boston, MA |publisher=Springer US |doi=10.1007/978-1-4684-8094-8_1 |isbn=978-1-4684-8096-2 |access-date=23 July 2022 |archive-date=30 July 2022 |archive-url=https://web.archive.org/web/20220730033922/https://link.springer.com/chapter/10.1007/978-1-4684-8094-8_1 |url-status=live }}</ref><ref>{{Cite book |last=Wang |first=Guanyu |url=https://www.worldcat.org/oclc/868928102 |title=Analysis of complex diseases : a mathematical perspective |date=2014 |publisher=CRC Press |isbn=978-1-4665-7223-2|oclc=868928102 |access-date=23 July 2022 |archive-date=30 July 2022 |archive-url=https://web.archive.org/web/20220730033921/https://www.worldcat.org/title/analysis-of-complex-diseases-a-mathematical-perspective/oclc/868928102 |url-status=live }}</ref><ref>{{Cite book |url=https://www.worldcat.org/oclc/906025831 |title=Climate change impact on livestock : adaptation and mitigation |date=2015 |publisher=Springer |editor-last1=Sejian |editor-first1=Veerasamy |editor-last2=Gaughan |editor-first2=John |editor-last3=Baumgard |editor-first3=Lance |editor-last4=Prasad |editor-first4=C. S. |isbn=978-81-322-2265-1 |oclc=906025831 |access-date=23 July 2022 |archive-date=30 July 2022 |archive-url=https://web.archive.org/web/20220730033921/https://www.worldcat.org/title/climate-change-impact-on-livestock-adaptation-and-mitigation/oclc/906025831 |url-status=live }}</ref>
# Response to [[stimulus (physiology)|stimuli]]: such as the contraction of a [[unicellular organism]] away from external chemicals, the complex reactions involving all the senses of [[multicellular organisms]], or the motion of the leaves of a plant turning toward the sun ([[phototropism]]), and [[chemotaxis]].
# [[Reproduction]]: the ability to produce new individual organisms, either [[asexual reproduction|asexually]] from a single parent organism or [[sexual reproduction|sexually]] from two parent organisms.