Definition of animals and their varying lifestyle
Answers
An animal (plural: animals) refers to any of the eukaryotic multicellular organisms of the biological kingdom Animalia generally characterized to be heterotrophic, motile, having specialized sensory organs, lacking a cell wall, and growing from a blastula during embryonic development. Etymology: Latin animale (neuter of animalis). Synonym: fauna.
Animal societies, in which collective action emerges from cooperation among individuals, represent extreme social complexity. Such societies are not only common in insects, mammals, and birds, but exist even in simple species like amoebas
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Answer:
Animals are multicellular organisms. The animal body is composed of several cells performing specific functions as opposed to bacteria and most protists that are unicellular. The cells may then be organized into various animal tissues, such as epithelial tissues, connective tissues, muscle tissues, nervous tissues, and vascular tissues. The cells in tissues may be held through cell junctions, e.g. tight junctions, gap junctions, and desmosomes.
Animals are eukaryotic. An animal cell contains a membrane-bound nucleus. The nucleus is the organelle that contains chromosomes that bear genes.
Animals are heterotrophic. Unlike plants and algae that are autotrophic, the animals depend on another organism for food.