BIOL 1080 Lecture Notes - Lecture 12: Pulmonary Vein, Pulmonary Artery, Circulatory System
Document Summary
The cardiovascular system: read pages 215-237, composed of three main components: Blood vessels conduits for blood flow. Blood vessel characteristics: arteries in arterial blood, arterioles, veins. Thin walled for easy expansion and recoiling. Think muscular walls designed to handle the high pressure: capillaries. A bit less muscle (pressures are now dropping), but there is lots of innervation to control smooth muscle contractions i. e. vessel diameter main site of bp regulation. No smooth muscle so there"s no control over diameter, or connective tissue no ability to withstand high pressures. But movement of fluid and solutes is maximized. Veins: blood is moved against gravity toward the heart by. Pressure gradient between left and right side of heart is facilitated by: Expansion of the thoracic cavity during breathing. Allow backwards flow of blood and pooling. Generally occurs in superficial veins in the thigh and calf (long saphenous vein)
