The Dirty Earthworm
Earthworm Dissection PreAp Biology 3/11/14 - Nima Desai 7th
The objective is to learn about the external and internal anatomy of a earthworm. Also focus on the organs, structures, and functions of the digestive system. Students will also understand the ecological role of the earthworm.
- Earthworms are tube-shaped, segmented animals that most commonly live in soil, and are only a few inches in length. Earthworms have setaes, or small bristles, which helps the worm to move and burrow. The scientific name for an earthworm is Lumbricus terrestris. Earthworms feed on live and dead organic matter and get eaten by predators like snakes, birds, rodents, and so many more which feed on Earthworms. The earthworm has no gills or lungs. Gases are exchanged between the circulatory system and the environment through the moist skin. Earthworms are seen after rain because they need the rain to help keep the skin moist and allow for gas exchange.
Do you know how to dissect a earthworm? If you don't, click on the link above to see how it works. This video also gives great information so if you want to know more about earthworms, click on the link above.
Digestive System Up Close
The digestive system has many regions, each with a certain function. The mouth, pharynx, esophagus, crop, intestine and gizzard are part of the digestive system. The food enters the threw the mouth where it is swallowed by the pharynx. After it passes through the esophagus, the food moves into the crop where it is stored and then eventually moves into the gizzard. The food moves into the intestines which processes the food. The intestinal wall contains blood vessels where the digested food is absorbed and transported to the rest of the body. The digestive System works closely with the circulatory system because when the food gets to the intestine the blood vessels absorb and transport the food.
Earthworms need to maintain moisture for air to pass threw the skin. This is why earthworms are found after rain.
Birds are one of many predators of the earthworms.
Mouth, Pharynx, Esophagus, Crop, Intestine and Gizzard
Humans impact the earthworm population by using them as bait for fishing. Fishers use earthworms to help catch fish. Sometimes fishes get away which require more earthworms to be used.
Confused about earthworms? Click to get more information about the history, anatomy, diet and so much more. You can also test yourself! Come join Herman the Worm!