BIOL 101 Lecture Notes - Lecture 19: Pulmonary Artery, Pulmonary Vein, Extracellular Fluid
Document Summary
Increased body size requires systems: dedicated delivery and removal. Blood in vessels separate from interstitial fluid. Amphibian & mammal: pulmonary circuit and systemic circuit [3-4 chambers & 2 circuits] Pulmonary circuit: blood is pumped form the heart to the lungs where it picks up oxygen. Systemic circuit: blood is pumped to the tissues of the body, where it delivers oxygen. Transports substances to and from cells: gasses (oxygen, carbon dioxide, nutrients, vitamins, hormones, waste, immune system cells, proteins. Two circuits of blood flow: pulmonary. Right atrium and right ventricle: systemic. Heart body (materials transported to/from cells) Arteries (thick wall, high pressure: vessels that carry blood away from the heart and to the capillaries. Capillaries (narrow, thin walls: tiny porous vessels that bring blood close to tissue, enabling the diffusion of gasses, nutrients, and other molecules into and out of the tissue. Veins (thinner walls, lower pressure: vessels that carry blood away from the capillaries back toward the heart.