BIOL 111 Study Guide - Final Guide: Blood Vessel, Nephridiopore, Gastrointestinal Tract

• School: McGill University
• Department: Biology (Sci)
• Course: BIOL 111
• Professor: Suzanne Gray

Document Summary

Daytime, remain underground to avoid drying out. Nighttime, come above ground to search for food and to mate. Thin transparent cuticle secreted by the epidermis to protect the worm. Mucus is also secreted from the glandular cells, aids in protection, locomotion as well as respiration. The anterior end is thicker than the posterior end. The clitellum is a thick band around the worm, found closer to the anterior end. The ventral side is flatter and lighter than the dorsal side. Respiratory, digestive, circulatory and nervous systems are found in the anterior end. Earth worm is divided into segments (each segment contains four pairs of setae (bristle like projections that aid in anchoring the worm to the substrate) Segment 1: the mouth; thin ventral slit contains the peristomium (fleshy lobe that surrounds the mouth and the protosmium (fleshly lobe that proceeds the mouth) Segment 9 to 10: contains the seminal receptacles, where the sperm is stored.