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EarthwormsEarthwormsPhylum AnnelidaPhylum Annelida
Class OligochaetaClass Oligochaeta
Where do earthworms live?Where do earthworms live?
They live in burrows in the dirtThey live in burrows in the dirt
They tunnel in the soil– this They tunnel in the soil– this helps the soil become loosehelps the soil become loose
It also cycles nutrients & lets air It also cycles nutrients & lets air inin
How do they move?How do they move?
They crawl using muscle They crawl using muscle contractions that shorten contractions that shorten and lengthen the bodyand lengthen the body
They can grip the soil using They can grip the soil using seteasetea or little hairs on the or little hairs on the ventral surfaceventral surface
Lots of mucusLots of mucus
External FeaturesExternal Features
Sensitive skin – can Sensitive skin – can sense light, touch & sense light, touch & chemicalschemicals
Mouth, anus, clitellum, Mouth, anus, clitellum, many segmentsmany segments
What do earthworms eat?What do earthworms eat?
Soil and the organic material in itSoil and the organic material in itThe food enters the mouth and The food enters the mouth and
pharynx where saliva gets it moistpharynx where saliva gets it moistThe crop stores it and the gizzard The crop stores it and the gizzard
grinds it upgrinds it upThe intestines absorb nutrients, the The intestines absorb nutrients, the
anus expels waste (castings)anus expels waste (castings)
Respiration, Circulation, Nervous Respiration, Circulation, Nervous SystemSystem
Diffusion of gases through Diffusion of gases through skinskin
5 pairs of hearts (10), 2 5 pairs of hearts (10), 2 main blood vesselsmain blood vessels
Simple nervous system with Simple nervous system with cerebral ganglion & ventral cerebral ganglion & ventral nerve cordnerve cord
ReproductionReproductionHermaphroditicHermaphroditic2 worms come together 2 worms come together
ventrally and exchange spermventrally and exchange spermLater the each worm excretes a Later the each worm excretes a
cocoon surrounding the worm, cocoon surrounding the worm, as it slides forward, the sperm is as it slides forward, the sperm is released and the eggs fertilized released and the eggs fertilized the worm slips out of the cocoonthe worm slips out of the cocoon
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