See also: Alive
In Biology and ecology, a living organism (of the Greek organon = instrument) is a Système complexes evolutionary formed of Organe S which interacts so that they function like a stable unit.
An organization is in a thermodynamic state of not-balance, preserving a Environnement homeostatic intern, and a continuous contribution of energy is necessary to maintain this state.
The Origin of life and the relation between its major lines are discussed. One can distinguish two independent groups, the Procaryote S and the Eucaryote S. the procaryotes are generally regarded as composed of two fields, called Bacteria and Archaea , which is as distant one from the other as they are to it eucaryotes. The interval between procaryotes and eucaryotes is largely regarded as a missing link in the History of the evolution. Two organoids eucaryotic S, namely the Mitochondrie and the Chloroplaste, are generally regarded as the result of the endosymbiose of a bacterium.
The term organization complexes described any organization with more cell.
General information
A living organism is a to be organized, which can be Unicellulaire or Pluricellulaire. It is difficult to define with precision what is the life. One can give some characteristics of the alive one:- capacity to be maintained in life by drawing from the environment energy necessary (the Métabolisme includes various functions, the Nutrition, the Respiration…) ;
- capacity to develop according to a certain organization (growth, morphology);
- capacity to reproduce (vegetative reproduction or sexuée);
- need for a favorable Environment to survive (Temperature, Pressure, Oxygen, Water…).
Any living organism is Mort el, by definition.
According to the energy source used, one distinguishes the Chimiotrophe S, drawing their energy from molecules and the autotrophic S, drawing their energy from the Sun.
A living organism is an organized whole of matter which tends to be maintained in a homeostatic state by a concerted use of energy.
Optional characteristics
Other frequent but not systematic characteristics are:- the Displacement (characteristic which excludes only the plants), which also exists at procaryotic organizations such as the bacteria (whip, pili);
- sensitivity to the Stimulus (generally external).
Classification
The living organisms are classified by the phylogenetic . The first subdivision includes/understands three fields:- the Archéobactérie S;
- the Eubactérie S;
- the Eucaryote S.
There exist entities close to the living organisms, which however are not regarded as such, because of an absence of metabolism: the Virus and the prion S. Cependant, these entities share with the living organisms the capacity to be retorted, i.e. to cause on behalf of their environment the production of copies of themselves (formulation of David Deutsch): they are réplicateurs.
See too
Simple: Organism Zh-min-nan: Seng-bu̍t Zh-yue: 生物
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