This preview shows page 1. Sign up to view the full content.
Unformatted text preview: to internal septa (walls) separating each body segment. The earthworm excretory system has coiled nephridia tubules in each segment with two openings: one is a ciliated funnel that collects coelomic fluid, and the other is an exit in the body wall. Between the two openings, the coiled nephridia tubule allows removal of waste materials from blood vessels. Red blood is moved anteriorly by a dorsal blood vessel and pumped by five pairs of hearts (sometimes referred to as aortic arches) to a ventral vessel. Earthworms are hermaphroditic, having both testes with seminal vesicles, and ovaries with seminal receptacles. Mating involves the worms lying parallel to each other facing opposite directions and exchanging sperm. Each worm possesses a clitellum that then secretes a mucus, protecting sperm and eggs from drying out. Embryonic development lacks a larval stage....
View Full Document
This note was uploaded on 11/29/2011 for the course BIO BSC1010 taught by Professor Gwenhauner during the Fall '10 term at Broward College.
- Fall '10