How does the skin of earthworm helps in Respiration?
Answers
Earthworms do not have lungs. They breathe through their skin. Oxygen and carbon dioxide pass through the earthworm’s skin by diffusion. For diffusion to occur, the earthworm’s skin must be kept moist. Body fluid and mucous is released to keep its skin moist. Earthworms therefore, need to be in damp or moist soil. This is one reason why they usually surface at night when it is possibly cooler and the “evaporating potential of the air is low.” Earthworms have developed the ability to detect light even though they cannot see. They have tissue located at the earthworm’s head that is sensitive to light. These tissues enable an earthworm to detect light and not surface during the daytime where they could be affected by the sun.
Earthworms are found in the soil. In the soil they eat dead and decaying organic matter along with soil. In return, they help in aeration of soil by digging holes in it and enhance fertility of soil. In earthworms there is no specialized organ to do respiration. So, in earthworms respiration process takes place through its moist, thin and highly vascular skin. The oxygen gas absorbed by the skin diffuses into the blood and transported to all the cells of the body. In the cells, oxygen is used up for oxidation of food. During this process, carbon dioxide is produced. Then, this carbon dioxide mixes in the blood and diffused out of the body through its moist skin.