Inside The World of an Earthworm
Earthworm Dissection Pre-AP Biology April 9, 2014- VU
Lumbricus terrestris
Earthworms, otherwise known as Lumbricus terrestris, fall under the phylum Annelida. They are streamlined to help them burrow and move through the soil. The mucus coating helps oxygen pass through its skin. Earthworms typically in warm, moist soil that's rich in nutrients. Their habitat is influenced by the climate and vegetation that area has. The earthworm has many predators like birds, raccoon, moles, snakes, and their biggest predator... man. Many cultures eat worms and farmers kill billions of them by plowing their fields and using harmful pesticides or chemical fertilizers.
Objectives
Student's will learn the internal and external anatomy of an earthworm. They will focus on the organs, structures, and functions of its digestive system.
External Anatomy
anterior end, mouth, seminal receptacles, oviduct openings, sperm duct openings, setae, clitellum, segments, anus, and prosterior end.
Internal Anatomy
prestonium, brain, pharynx, testes, heart, seminal receptacles, esophagus, ovaries, crop, gizzard, seminal vesicles, dorsal blood vessel, nephridia, clitellum, intestine, ventral blood vessel, and central nerve chord.
Digestive System
mouth, pharynx, esophogus, crop, gizzard
Diving into an Earthworm's Digestive System
An Earthworm’s digestive system consists of mouth, pharynx, esophagus, crop, gizzard and intestine. The food particles pass from the mouth to the pharynx where the food is lubricated by mucus secretions to make it easier to pass to the esophagus. After that, the food gets mixed together in the crop and from there it is passed on to the gizzard where the real digestion process begins. Next, the mixture is sent to the intestine where various minerals, carbohydrates, vitamins, and proteins are released to supply the worm with the nutrients it needs
You Take A Look!
Earthworm Dissection Lab