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The
chordata is one phylum of animals. One subphylum of chordata
is
divided into
five classes. Each class has its own unique features. |
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Characteristics
of Animals |
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Animals
have certain features that together make them different
from other organisms. First, animals are multicellular—they
are
made of more than one cell. The bears shown on this page are
made of trillions of cells. Second, animals cannot make their
own food. In order to get energy, animals must eat other
organisms. Third, animals can move on their own during part
or all of their lives. |
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Vertebrate Animals |
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Today, the animal
kingdom is divided into more than 30 phyla.
Only one phylum, the chordata, contains organisms that have
spinal cords. One subphylum of this group contains animals
with backbones that surround the spinal cord. These animals
are called vertebrates. Backbones protect a very important
set
of nerves that go to the brain. Bison and sheep are vertebrates.
What other vertebrates do you know? This subphylum is divided
into five classes. The classes are mammals, birds, reptiles,
amphibians, and fish. |
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