The Earthy Earthworm
Rachel Shen. Vu-PAPBio-P2. Earthworm Dissection.
The Earthworm (Lumbricus terrestris)
Dissecting the Earthworm
The earthworm was very hard to dissect since it was very thin and long. Its skin was thin and it had tiny organs. It was hard to pin down some of the skin at first but it was done after a few times. Its main organs are near the top (the head/mouth) of the earthworm (anterior end) and its anus is at the opposite end (posterior end).
Objectives of the Worm of the Earth
The earthworm (starting from the anterior end) consists of the prostomium, the mouth, seminal receptacles (9, 10), oviduct openings (14), sperm duct openings (15), setae, clitellum (32), and an anus (at the posterior end).
The earthworm consists of many different organs like humans do as well. However, it is much more simple than the human body. The earthworm consists of mainly of a buccal cavity, pharynx, heart, seminal receptacles, seminal vesicles, crop, gizzard, septa, and dorsal blood vessel.
The earthworm has a closed circulatory system. The blood is circulated through the 3 main different types of vessels. These vessels are ventral blood vessels, aortic vessels, and dorsal blood vessels. The aortic vessels are responsible for pumping blood. The ventral blood vessels carry blood towards the posterior end as the dorsal blood vessels carry blood towards the anterior end.
The Digestive System
Did you know that the earthworm contains both male and female reproductive parts?
Did you know that an earthworm does not have a real heart but these things that work as a heart called aortic arches?
Did you know that earthworms reproduce by sliding past each other?
Did you know that an earthworm has bilateral symmetry?
Did you know that the earthworm's skin is used for the diffusion of O2 and CO2?