Earthworm

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Phylum Annelida- Segmented Worms
Earthworm
Fire worm
Leech
Feather duster worm
Christmas tree worm
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Segmented worms such as earthworms have bodies
made up of many linked sections called segments.
They dont have a smooth outer body like
roundworms. Like roundworms, segmented worms
have a one way digestive tract with two openings,
a mouth and an anus. Just as in flatworms and
roundworms some segmented worms are parasitic,
for example a leech is a type of parasitic
segmented worms. Segmented worms have a
closed circulatory system, this means that blood
only moves within a connected network of tubes
called blood vessels. In contrast, some animals,
such as insects, have an open circulatory system
in which blood leaves the blood vessels and
sloshed around the body. A closed system works
more efficiently and can deliver oxygen and food
to cells more quickly. Earthworms are the most
recognizable type of segmented worm. They are
very helpful inhabitants of gardens and farms
because their droppings make soil more fertile.
They also help loosen soil and allow air, water
and plant roots to move easily through it.
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