Biological systems

An organism is any living thing that functions as an individual. Such a definition raises more problems than it solves, not least because the concept of an individual is also difficult. Several criteria, few of which are widely accepted, have been proposed to define what constitutes an organism. Among the most common is that an organism has autonomous reproduction, growth, and metabolism. This would exclude viruses, even though they evolve like organisms.

thumb|A false color composite of global oceanic and terrestrial photoautotroph abundance, from September 2001 to August 2017. Provided by the [[SeaWiFS Project, NASA/Goddard Space Flight Center and ORBIMAGE.]]

major work by Carolus Linnaeus

argument by proponents of intelligent design that certain biological systems are too complex to have evolved

complex network of biologically relevant entities on the macro to the nanoscopic scale

description of the element's function as an essential mineral micronutrient

hypothesis in neuroscience proposed by Karl Friston

Use of Magnesium by organisms

broad-based engineering discipline with particular emphasis on biology and chemistry

Use of Sodium by organisms

open self-organizing living things that interact with their environment

Loss of all biotic/abiotic features in an ecosystem

ability of an ecosystem to recover from damage

model for simulation of ecological relations and effects

Use of Iron by organisms

life in the deep subsurface of the Earth

book by Carl Alexander Clerck

Use of Potassium by organisms