| A | B |
|---|
| alveolus | multilobed air sacs that constitute the gas exchange surface of the lungs |
| arteriole | vessel that conveys blood between an artery and a capillary bed |
| artery | vessel that carries blood away from the heart to organs throughout the body |
| atherosclerosis | disease in which growths called plaques develop on the inner walls of the arteries narrowing their inner diameters |
| atrioventricular (AV) node | generates electrical impulses that primarily cause the ventricles to contract |
| atrioventricular valve | valve in the heart between each atrium and ventricle that prevents a backflow of blood |
| atrium | chamber that receives blood returning to the vertebrate heart |
| blood | fluid matrix called plasma in which blood cells are suspended |
| blood pressure | hydrostatic force that blood exerts against the wall of a vessel |
| blood vessels | tubes through which the blood moves through the body |
| Bohr shift | lowering of the affinity of hemoglobin for oxygen facilitates the release of oxygen from hemoglobin in the vicinity of active tissues |
| breathing | process involving alternate inhalation and exhalation of air that ventilates the lungs |
| breathing control center | directs the activity of organs involved in breathing |
| bronchiole | fine branches of the bronchus that transport air to alveoli |
| bronchus | pair of breathing tubes that branch from the trachea into the lungs |
| capillary | consists of a single layer of endothelial cells that allows exchange between the blood and interstitial fluid |
| capillary bed | network of capillaries that infiltrate every organ and tissue in the body |
| cardiac cycle | alternating contractions and relaxations of the heart |
| cardiac output | volume of blood pumped per minute by the left ventricle of the heart |
| cardiovascular disease | diseases of the heart and blood vessels |
| cardiovascular system | closed circulatory system with a heart and branching network of arteries |
| closed circulatory system | blood is confined to vessels and is kept separate from the interstitial fluid |
| countercurrent exchange | opposite flow of adjacent fluids that maximizes transfer rates |
| diaphragm | muscle that forms the bottom wall of the thoracic cavity in mammals |
| diastole | stage of the heart cycle in which the heart muscle is relaxed |
| diastolic pressure | blood pressure that remains between heart contractions |
| dissociation curve | chart showing the relative amounts of oxygen bound to hemoglobin when the pigment is exposed to solutions varying in their partial pressure of dissolved oxygen |
| double circulation | scheme with separate pulmonary and systemic circuits |
| electrocardiogram (ECG or EKG) | record of the electrical impulses that travel through cardiac muscle during the heart cycle |
| endothelium | simple squamous layer of cells lining the blood vessels |
| erythrocyte | hemoglobin bearing ed blood cell in transporting oxygen in the circulatory system |
| erythropoietin | hormone stimulates the production of erythrocytes |
| fibrin | aggregates into threads that form the fabric of the clot |
| fibrinogen | inactive form of the plasma protein that is converted to the active form fibrin |
| gas exchange | uptake of molecular oxygen from the environment and the discharge of carbon dioxide to the environment |
| gill | localized extension of the body surface of many aquatic animals specialized for gas exchange |
| gill circulation | flow of blood through gills |
| heart | muscular pump that uses metabolic energy to elevate hydrostatic pressure of the blood |
| heart attack | death of cardiac muscle tissue resulting from prolonged blockage of one or more coronary arteries |
| heart murmur | hissing sound that occurs when blood squirts backward through a leaky valve in the heart |
| heart rate | rate of heart contraction |
| hemocyanin | respiratory pigment that uses copper as its oxygen-binding component |
| hemoglobin | iron-containing protein in red blood cells that reversibly binds oxygen |
| hemolymph | open circulatory system the body fluid that bathes tissues |
| hemophilia | genetic disease caused by a sex-linked recessive allele characterized by excessive bleeding following injury |
| high-density lipoprotein (HDL) | cholesterol-carrying particle in the blood good cholesterol |
| hypertension | chronically high blood pressure within the arteries |
| larynx | voice box containing the vocal cords |
| leukocyte | white blood cell typically functions in immunity |
| low-density lipoprotein (LDL) | cholesterol-carrying particle in the blood bad cholesterol |
| lung | invaginated respiratory surface of terrestrial vertebrates |
| lymph | colorless fluid derived from interstitial fluid |
| lymph node | lymph and help attack viruses and bacteria |
| lymphatic system | system of vessels and lymph nodes separate from the circulatory system that returns fluid to the blood |
| myogenic heart | pacemaker is made up of specialized muscle tissues and located within the heart itself |
| myoglobin | oxygen-storing muscle fibers |
| negative pressure breathing | breathing system in which air is pulled into the lungs |
| neurogenic heart | pacemakers originate in motor nerves arising from outside the heart |
| open circulatory system | fluid called hemolymph bathes the tissues and organs directly |
| pacemaker | specialized region of the right atrium sets the rate of contraction |
| parabronchus (plural | tubes for one way air flow in lungs of birds |
| partial pressure | measure of the concentration of one gas in a mixture of gases |
| peripheral resistance | impedance of blood flow by the arterioles |
| plasma | liquid matrix of blood in which the cells are suspended |
| platelet | enucleated blood cell important in blood clotting |
| positive pressure breathing | breathing system in which air is forced into the lungs |
| pulmocutaneous circuit | route of circulation that directs blood to the skin and lungs |
| pulmonary circuit | branch of the circulatory system that supplies the lungs |
| pulse | rhythmic stretching of the arteries caused by the pressure of blood forced through the arteries by contractions of the ventricles during systole |
| red blood cell | blood cell containing hemoglobin |
| residual volume | amount of air that remains in the lungs after forcefully exhaling |
| respiratory medium | source of oxygen. It is typically air for terrestrial animals and water for aquatic organisms |
| respiratory pigment | special protein that transports most of the oxygen in blood |
| respiratory surface | part of an animal where gases are exchanged with the environment |
| semilunar valve | valve located at the two exits of the heart |
| sinoatrial (SA) node | region of the heart composed of specialized muscle tissue that sets the rate and timing at which all cardiac muscle cells contract |
| sinus | spaces surrounding the organs of the body in animals with open circulatory systems |
| stem cell | cell that can divide during a single division into one identical daughter cell and one more specialized daughter cell |
| stroke | death of nervous tissue in the brain |
| stroke volume | amount of blood pumped by the left ventricle in each contraction |
| systemic circuit | branch of the circulatory system that supplies all body organs and then returns oxygen-poor blood to the right atrium |
| systemic circulation | Movement of blood through the systemic circuit |
| systole | stage of the heart cycle in which the heart muscle contracts |
| systolic pressure | blood pressure in the arteries during contraction of the ventricles |
| thrombus | clump of platelets and fibrin that blocks the flow of blood through a blood vessel |
| tidal volume | volume of air an animal inhales and exhales with each breath |
| trachea | portion of the respiratory tube that has C-shaped cartilagenous rings and passes from the larynx to two bronch |
| tracheal system | gas exchange system of branched chitin-lined tubes that infiltrate the body and carry oxygen directly to cells in insects |
| vein | vessel that returns blood to the heart |
| ventilation | method of increasing contact between the respiratory medium and the respiratory surface |
| ventricle | heart chamber that pumps blood out of a heart |
| venule | vessel that conveys blood between a capillary bed and a vein |
| vital capacity | maximum volume of air that a respiratory system can inhale and exhale |
| vocal cord | string-like tissues in the larynx |
| white blood cell | cell that functions in defending the body against infections and cancer cells |
