what is life
LifeΒ is a quality that distinguishesΒ matterΒ that hasΒ biological processes, such asΒ signalingΒ and self-sustaining processes, from matter that does not, and is defined descriptively by the capacity forΒ homeostasis,Β organisation,Β metabolism,Β growth,Β adaptation, response toΒ stimuli, andΒ reproduction. Many philosophical definitions ofΒ living systemsΒ have been proposed, such asΒ self-organizingΒ systems.Β VirusesΒ in particular make definition difficult as they replicate only inΒ hostΒ cells. Life exists all over the Earth in air, water, and soil, with manyΒ ecosystemsΒ forming theΒ biosphere. Some of these are harsh environments occupied only byΒ extremophiles.














