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- Current: Jun 20, 2022
Animal
Animals are a group of organisms that meet all of the following conditions.
- Eukaryotic
- Multicellular
- Lacking a cell wall
- Consumer
Tubeworms and corals obtain energy from symbiotic bacteria. While they do not feed the bacteria, they are still considered to be animals based on the definition of consumer.
The following features can be seen in most animals [2].
- Reproduce sexually
- Motile
- Rapidly respond to environmental stimuli (compared to plants)
Definitions in the literature
- A multicelled, eukaryotic consumer that is made up of unwalled cells and develops through a series of stages. Most ingest food, reproduce sexually, and can move from to place to place [1].
- No single feature uniquely defines animals, so the group is defined by a list of characteristics [2].
