BIO 102 Lecture Notes - Lecture 15: Superior Vena Cava, Pulmonary Artery, Red Blood Cell
17 Apr 2017
School
Department
Course
Professor
Document Summary
Arteries bring blood away from heart, veins bring blood to heart. All circulatory systems have three major parts: Blood (transport gases, nutrients, and cellular waster) One or more simple hearts, some blood vessels, series of interconnected spaces within the body (hemocoel) Within hemocoel - tissues and organs are in a fluid (hemolymph) that acts as blood and the extracellular (interstitial) fluid that surrounds each cell within a multicellular organism. Heart chambers contract valves in heart are pressed shut hemolymph forced out through vessels and into hemocoel spaces throughout the body. Chambers relax hemolymph drawn back into them from the hemocoel. Confine the blood to the heart and to vessels that carry blood throughout the body. Blood pressure and flow rates are higher (than what is possible in open system) Better able to direct blood to specific tissues as needed delivering o2 and nutrients. Present in: all vertebrates, a few invertebrates, earthworms. Transport o2 and co2 (gills or lungs)
