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93 Cards in this Set

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  • Back
One of the dead-end, multilobed air sacs that constitute the gas exchange surface of the lungs.
A vessel that conveys blood between an artery and a capillary bed.
A vessel that carries blood away from the heart to organs throughout the body.
A cardiovascular disease in which growths called plaques develop on the inner walls of the arteries, narrowing their inner diameters.
atrioventricular (AV) node
A region of specialized muscle tissue between the right atrium and right ventricle. It generates electrical impulses that primarily cause the ventricles to contract.
atrioventricular valve
A valve in the heart between each atrium and ventricle that prevents a backflow of blood when the ventricles contract.
A chamber that receives blood returning to the vertebrate heart.
A type of connective tissue with a fluid matrix called plasma in which blood cells are suspended.
blood pressure
The hydrostatic force that blood exerts against the wall of a vessel.
blood vessels
A set of tubes through which the blood moves through the body.
Bohr shift
A lowering of the affinity of hemoglobin for oxygen, caused by a drop in pH; facilitates the release of oxygen from hemoglobin in the vicinity of active tissues.
The process involving alternate inhalation and exhalation of air that ventilates the lungs.
breathing control center
A brain center that directs the activity of organs involved in breathing.
One of the fine branches of the bronchus that transport air to alveoli.
One of a pair of breathing tubes that branch from the trachea into the lungs.
A microscopic blood vessel that penetrates the tissues and consists of a single layer of endothelial cells that allows exchange between the blood and interstitial fluid.
capillary bed
A network of capillaries that infiltrate every organ and tissue in the body.
cardiac cycle
The alternating contractions and relaxations of the heart.
cardiac output
The volume of blood pumped per minute by the left ventricle of the heart.
cardiovascular disease
Diseases of the heart and blood vessels.
cardiovascular system
A closed circulatory system with a heart and branching network of arteries, capillaries, and veins. The system is characteristic of vertebrates.
closed circulatory system
A circulatory system in which blood is confined to vessels and is kept separate from the interstitial fluid.
countercurrent exchange
The opposite flow of adjacent fluids that maximizes transfer rates; for example, blood in the gills flows in the opposite direction in which water passes over the gills, maximizing oxygen uptake and carbon dioxide loss.
A sheet of muscle that forms the bottom wall of the thoracic cavity in mammals; active in ventilating the lungs.
The stage of the heart cycle in which the heart muscle is relaxed, allowing the chambers to fill with blood.
diastolic pressure
Blood pressure that remains between heart contractions.
dissociation curve
A 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
A circulation scheme with separate pulmonary and systemic circuits, which ensures vigorous blood flow to all organs.
electrocardiogram (ECG or EKG)
A record of the electrical impulses that travel through cardiac muscle during the heart cycle.
The innermost, simple squamous layer of cells lining the blood vessels; the only constituent structure of capillaries.
A red blood cell; contains hemoglobin, which functions in transporting oxygen in the circulatory system.
A hormone produced in the kidney when tissues of the body do not receive enough oxygen. This hormone stimulates the production of erythrocytes.
The activated form of the blood-clotting protein fibrinogen, which aggregates into threads that form the fabric of the clot.
The inactive form of the plasma protein that is converted to the active form fibrin, which aggregates into threads that form the framework of a blood clot.
gas exchange
The uptake of molecular oxygen from the environment and the discharge of carbon dioxide to the environment.
A localized extension of the body surface of many aquatic animals, specialized for gas exchange.
gill circulation
The flow of blood through gills.
A muscular pump that uses metabolic energy to elevate hydrostatic pressure of the blood. Blood then flows down a pressure gradient through blood vessels that eventually return blood to the heart.
heart attack
The death of cardiac muscle tissue resulting from prolonged blockage of one or more coronary arteries.
heart murmur
A hissing sound that occurs when blood squirts backward through a leaky valve in the heart.
heart rate
The rate of heart contraction.
A type of respiratory pigment that uses copper as its oxygen-binding component. Hemocyanin is found in the hemolymph of arthropods and many molluscs.
An iron-containing protein in red blood cells that reversibly binds oxygen.
In invertebrates with an open circulatory system, the body fluid that bathes tissues.
high-density lipoprotein (HDL)
A cholesterol-carrying particle in the blood, made up of cholesterol and other lipids surrounded by a single layer of phospholipids in which proteins are embedded. An HDL particle carries less cholesterol than a related lipoprotein, LDL, and may be correlated with a decreased risk of blood vessel blockage.
Chronically high blood pressure within the arteries.
The voice box, containing the vocal cords.
A white blood cell; typically functions in immunity, such as phagocytosis or antibody production.
low-density lipoprotein (LDL)
A cholesterol-carrying particle in the blood, made up of cholesterol and other lipids surrounded by a single layer of phospholipids in which proteins are embedded. An LDL particle carries more cholesterol than a related lipoprotein, HDL, and high LDL levels in the blood correlate with a tendency to develop blocked blood vessels and heart disease.
An invaginated respiratory surface of terrestrial vertebrates, land snails, and spiders that connects to the atmosphere by narrow tubes.
The colorless fluid, derived from interstitial fluid, in the lymphatic system of vertebrate animals.
lymph node
Organ located along a lymph vessel. Lymph nodes filter lymph and help attack viruses and bacteria.
lymphatic system
A system of vessels and lymph nodes, separate from the circulatory system, that returns fluid, proteins, and cells to the blood.
myogenic heart
A type of heart, such as in vertebrate animals, in which the pacemaker is made up of specialized muscle tissues and located within the heart itself.
An oxygen-storing, pigmented protein in muscle cells.
negative pressure breathing
A breathing system in which air is pulled into the lungs.
neurogenic heart
A type of heart, such as in insects, in which the pacemakers originate in motor nerves arising from outside the heart.
open circulatory system
A circulatory system in which fluid called hemolymph bathes the tissues and organs directly and there is no distinction between the circulating fluid and the interstitial fluid.
A specialized region of the right atrium of the mammalian heart that sets the rate of contraction; also called the sinoatrial (SA) node.
parabronchus (plural, parabronchi)
A site of gas exchange in bird lungs. Parabronchi allow air to flow past the respiratory surface in just one direction.
partial pressure
A measure of the concentration of one gas in a mixture of gases; the pressure exerted by a particular gas in a mixture of gases (for instance, the pressure exerted by oxygen in air).
peripheral resistance
The impedance of blood flow by the arterioles.
The liquid matrix of blood in which the cells are suspended.
A small enucleated blood cell important in blood clotting; derived from large cells in the bone marrow.
positive pressure breathing
A breathing system in which air is forced into the lungs.
pulmocutaneous circuit
The route of circulation that directs blood to the skin and lungs.
The 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
A blood cell containing hemoglobin, which transports O2; also called an erythrocyte
residual volume
The amount of air that remains in the lungs after forcefully exhaling.
respiratory medium
The source of oxygen. It is typically air for terrestrial animals and water for aquatic organisms.
respiratory pigment
A special protein that transports most of the oxygen in blood.
respiratory surface
The part of an animal where gases are exchanged with the environment.
semilunar valve
A valve located at the two exits of the heart, where the aorta leaves the left ventricle and the pulmonary artery leaves the right ventricle.
sinoatrial (SA) node
A region of the heart composed of specialized muscle tissue that sets the rate and timing at which all cardiac muscle cells contract.
Any of the spaces surrounding the organs of the body in animals with open circulatory systems.
stem cell
Any relatively unspecialized cell that can divide during a single division into one identical daughter cell and one more specialized daughter cell, which can undergo further differentiation.
The death of nervous tissue in the brain, usually resulting from rupture or blockage of arteries in the head.
stroke volume
The amount of blood pumped by the left ventricle in each contraction.
systemic circuit
The branch of the circulatory system that supplies all body organs and then returns oxygen-poor blood to the right atrium via the veins.
systemic circulation
Movement of blood through the systemic circuit.
The stage of the heart cycle in which the heart muscle contracts and the chambers pump blood.
systolic pressure
Blood pressure in the arteries during contraction of the ventricles.
A clump of platelets and fibrin that blocks the flow of blood through a blood vessel.
tidal volume
The volume of air an animal inhales and exhales with each breath.
The windpipe; that portion of the respiratory tube that has C-shaped cartilagenous rings and passes from the larynx to two bronchi.
tracheal system
A gas exchange system of branched, chitin-lined tubes that infiltrate the body and carry oxygen directly to cells in insects.
(1) In animals, a vessel that returns blood to the heart. (2) In plants, a vascular bundle in a leaf.
Any method of increasing contact between the respiratory medium and the respiratory surface.
(1) A heart chamber that pumps blood out of a heart. (2) A space in the vertebrate brain, filled with cerebrospinal fluid.
A vessel that conveys blood between a capillary bed and a vein.
vital capacity
The maximum volume of air that a respiratory system can inhale and exhale.
vocal cord
One of a pair of string-like tissues in the larynx. Air rushing past the tensed vocal cords makes them vibrate, producing sounds.
white blood cell
A blood cell that functions in defending the body against infections and cancer cells; also called a leukocyte.