| A | B |
|---|
| closed circulatory system | blood remains in vessels and exchanges materials with interstitial fluid bathing cells |
| cardiovascular system | heart, blood vessels, and blood |
| atria | receive blood |
| ventricles | pump blood out of the heart |
| arteries | carries blood away from heart |
| capillary beds | exchange of substances between blood and interstitial fluid occurs |
| veins | return blood to the heart |
| pulmocutaneous circuit | leads to lungs and skin capillaries and then back to the left atrium; amphibians |
| systemic circuit | carries blood to the rest of the body and back to the right atrium; amphibians |
| pulmonary circuit | gas exchange tissues in the lungs and through a systemic circuit to the body tissues |
| atrioventricular (AV) valves | between each atrium and ventricle are snapped shut when blood is forced back against them as the ventricles contract |
| semilunar valves | at the exit of hte aorta and pulmonary artery are forced open by ventricular contraction and close when the ventricles relax and blood starts to flow back toward the ventricles |
| heart rate | heartbeats per minute |
| pulse | rhythmic stretching of arteries as the ventricles contract and pump blood through them |
| systole | cardiac muscle contracts and the chambers pump blood |
| diastole | heart chambers are relaxed and filling with blood |
| cardiac output | volume of blood pumped per minute into the systemic circuit, depends on heart rate and stroke volume |
| stroke volume | quantity of blood pumped by each contraction of the left ventricle |
| sinoatrial (SA) node | coordinates rhythm of contractions--pacemaker |
| atrioventricular (AV) node | relays the impulse after a 0.1 second delay through fibers to all parts of the ventricular walls, causing contraction |
| blood pressure | hydrostatic force exerted against the wall of a blood vessel, is much greater in arteries than in veins and is greatest during systole |
| peripheral resistance | caused by narrow openings of the arterioles impeding the exit of blood from arteries, causes swelling of the arteries during systole |
| lymphatic system | returns fluid to the blood and aids in body defense |
| lymp nodes | lymph is filtered and WBCs attack viruses and bacteria |
| hemoglobin | iron containing protein that binds oxygen |
| platelets | pinced off fragments of large cells in the bone marrow, involved in the blood clotting mechanism |
| pluripotent stem cells | red and white blood cells produced from in red bone marrow |
| thrombus | a clot that occurs within a blood vessel and blocks the flow of blood |
| heart attack | blockage of coronary arteries |
| stroke | blockage of arteries in the head |
| atherosclerosis | gwrowths called plaques develop within arteries and narrow the vessels |
| arteriosclerosis | hardening of the arteries |
| low-density lipoproteins (LDLs) | cholesterol deposits in plaques |
| high-density lipoproteins (HDLs) | cholesterol carriers that appear to reduce cholesterol deposition in plaques |
| gas exchange | supplies oxygen for cellular respiration and disposes of carbon dioxide |
| respiratory surface | gas exchange with the respiratory medium occurs |
| gills | respiratory adaptations of most aquatic animals |
| countercurrent exchange | diffusion gradient favors the movement of oxygen into the blood throughout the length of the capillary |
| ventilation | any method of increasing the flow of the respiratory medium or the respiratory surface, brings in fresh supply of O2 and CO2 |
| tidal volume | volume of air inhaled and exhaled by an animal during normal breathing |
| vital capacity | maximum volume that can be inhaled and exhaled by forced breathing |
| residual volume | air that remains in the alveoli and lungs after forceful exhaling |
