Earthworm Dissection Lab
by: Deborah Adane Vu-PAP Bio-2
Earthworm life cycle
After earthworms mate, their fertilised eggs are held in a protective cocoon. The baby worms (hatchlings) emerge and burrow into the soil, where they grow into juvenile then mature worms.
Earthworms live at or under the surface of the soil.
The digestive system consists of the pharynx, the esophagus, the crop, the intestine and the gizzard. Food such as soil enters the earthworm’s mouth where it is swallowed by the pharynx. Then the soil passes through the esophagus, which has calciferous glands that release calcium carbonate to rid the earthworm’s body of excess calcium. After it passes through the esophagus, the food moves into the crop where it is stored and then eventually moves into the gizzard. The gizzard uses stones that the earthworm eats to grind the food completely. The food moves into the intestines as gland cells in the intestine release fluids to aid in the digestive process. The intestinal wall contains blood vessels where the digested food is absorbed and transported to the rest of the body.