BIOL 1202 Chapter : Test 5 Notes Part 1 Ch 42 43
Document Summary
42 circulation and gas exchange (circulatory and respiratory system) 42. 1 circulatory systems link exchange surfaces with cells throughout the body transport systems functionally connect the organs of exchange with the body cells. Gastrovascular cavities (cnidarians and flatworms) simple animals like cnidarians have a body wall that"s diploblastic (2-cell layers thick) between external environment and gastrovascular cavity gastrovascular cavity function both in digestion and circulation. More complex animals have 2 types of circulatory systems. Open circulatory system: blood bathes the organs directly. Closed circulatory system: blood is confined to vessels and is distinct from the interstitial fluid (exchange is between epithelium) Ex) some invertebrates (annelid and cephalopods) and all vertebrates. Mammals/birds have 4 chambered heart with double circulation (pulmonary and systemic circuit) Both of these types of systems have 3 components: circulatory fluid (blood, muscular pump (heart) Q: an open circulatory system allows blood and interstitial fluid to mix with each other. 42. 2 heart contraction drives double circulation in mammals.
