It is a synonym for " life form ". Organisms are classified by taxonomy into groups such as multicellular animals , plants , and fungi ; or unicellular microorganisms such as protists , bacteria , and archaea. Humans , squids , mushrooms , and vascular plants are examples of multicellular organisms that differentiate specialized tissues and organs during development. An organism may be either a prokaryote or a eukaryote. Eukaryotic organisms are characterized by the presence of a membrane-bound cell nucleus and contain additional membrane-bound compartments called organelles such as mitochondria in animals and plants and plastids in plants and algae , all generally considered to be derived from endosymbiotic bacteria. Estimates on the number of Earth's current species range from 2 million to 1 trillion,  of which over 1. In , a set of genes from the last universal common ancestor LUCA of all organisms was identified. It is directly related to the term "organization". There is a long tradition of defining organisms as self-organizing beings, going back at least to Immanuel Kant 's Critique of Judgment. An organism may be defined as an assembly of molecules functioning as a more or less stable whole that exhibits the properties of life.
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OTHER WORDS FROM organism
To save this word, you'll need to log in. Recent Examples on the Web In these cases, as in neuronal life, memory expresses itself through priming and triggering events that cause the organism or the system to respond in a way that improves overall fitness. Send us feedback. See more words from the same year Dictionary Entries near organism organic synthesis organing organisation organism organismic psychology organist organistic. Accessed 31 Aug. Keep scrolling for more More Definitions for organism organism.
Biology definition of organism: a living thing that has an organized structure, can react to stimuli, reproduce, grow, adapt, and maintain homeostasis. An organism refers to a living thing that has an organized structure, can react to stimuli , reproduce, grow , adapt, and maintain homeostasis. An organism would, therefore, be any animal , plant , fungus , protist , bacterium , or archaeon on earth. These organisms may be classified in various ways. One of the ways is by basing upon the number of cell s that make it up. The two major groups are the single-celled e. Organisms can also be classified according to their subcellular structures. Those with a well-defined nucleus are referred to as eukaryotes whereas those without are called prokaryotes. Both of them possess a genetic material but the location differs.
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