Feeding:Their nutrition comes from things in soil, such as decaying roots and leaves. Animal manures are an important food source for earthworms. They eat living organisms such as nematodes, protozoans, rotifers, bacteria, fungi in soil. Worms will also feed on the decomposing remains of other animals.
Internal Transport: Most have blood with hemoglobin, a red pigment that carries oxygen, but some others have a green pigment that carries oxygen, or unpigmented blood. Most segmented worms (such as earthworms) have a closed circulatory system which means the blood circulates only within a system of blood vessels, rather than mixing with fluid in the body cavity..
Response: Earthworms have no eyes,ears or nose. They can sense light and dark by small light sensitive cells found mainly on the upper skin surface at the ends of their body. They sense vibration and chemicals by the means of tiny touch or chemical sensitive cells.Earthworm move away from light, vibrations and dangerous chemicles.
Reproduction:Earthworms are simultaneous hermaphrodites, meaning worms have both male and female reproductive organs. During sexual intercourse among earthworms, both sets of sex organs are used by both worms. If all goes well, the eggs of both of the mates become fertilized. You can imagine this is a highly efficient way of ensuring the survival of the species.
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Respiration:Instead of lungs, earthworms have a thin permeable skin through which oxygen in air passes through.The oxygen does not directly pass through the earthworm’s thin outer skin. Instead, the oxygen must first mix with the moist slime on the earthworms skin. It is this mixture that passes through the skin as well as the very thin tissue of capillaries under the skin
Excretion: Digestion is similar to that of human beings except an earthworm has a crop and a gizzard. A worm actually sucks in its food. From the pharynx, the food moves to the esophagus and then into the crop for storage until the rest of the tract is clear. From there the food moves to the gizzard where the soil is ground up with little stones, releasing organic matter.
Movement: Earthworms have fluids skeleton. They move by squeezing the circular muscles of each segment to make their body extend forward, then they grip the surface with their bristles and contract their longitudinal muscles so their body is pulled up to their anterior end.
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