Animals are classified as multicellular, eukaryotic organisms belonging to the kingdom Animalia. They are characterized by the following features:
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Multicellular Structure: Animals are composed of multiple cells that work together, unlike single-celled organisms.
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Eukaryotic Cells: Their cells have a nucleus and other membrane-bound organelles, distinguishing them from prokaryotic organisms like bacteria.
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Heterotrophic Metabolism: Animals are heterotrophs, meaning they obtain their food by consuming other organisms, either plants or other animals, rather than producing their own food through photosynthesis as plants do.
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Mobility: Most animals have the ability to move at some stage of their life, which is often facilitated by specialized muscles and nervous systems.
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Reproduction: Animals reproduce mainly through sexual reproduction, although many also have asexual reproduction methods.
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Complex Tissue Structures: Animals have specialized cells that form tissues and organs, allowing for greater complexity and specialization in function.
Animals can be further divided into various groups, such as vertebrates (with a backbone) and invertebrates (without a backbone), with numerous phyla and classes within each group. Examples include mammals, birds, reptiles, amphibians, fishes, insects, and many others.