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Noun, pl. animals

1. A living organism belonging to Kingdom Animalia that possess several characteristics that set them apart from other living things, such as:

a. being eukaryotic (i.e. the cell contains a membrane-bound nucleus) and usually multicellular (unlike bacteria and most protists, an animal is composed of several cells performing specific functions) ;
b. being heterotrophic (unlike plants and algae that are autotrophic, an animal depends on another organism for sustenance) and generally digesting food in an internal chamber (such as a digestive tract);
c. lacking cell wall (unlike plants, algae and some fungi that possess cell walls);
d. being generally motile, that is being able to move voluntarily;
e. embryos passing through a blastula stage;
f.  possessing specialized sensory organs for recognizing and responding to stimuli in the environment.


2. A living organism that feeds on organic matter, typically having specialized sense organs and nervous system and able to respond rapidly to stimuli. (


1. Of or relating to animals (

Word origin: Middle English, from Latin, from animāle, neuter of animālis, living, from anima, soul.

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