Biology II - Chapter 42 - Circulation and Gas Exchange

A muscular pump that uses metabolic energy to elevate the hydrostatic pressure of the circulatory fluid (blood or hemolymph). The fluid then flows down a pressure gradient through the body and eventually returns to the heart.

In insects, a system of branched, air-filled tubes that extends throughout the body and carries oxygen directly to the cells.

A decrease in the diameter of blood vessels caused by contraction of smooth muscles in the vessel walls.

The alternating contractions and relaxations of the heart.

In invertebrates with an open ciculatory system, the body fluid that bathes tissues.

A vessel that conveys blood between a capillary bed and a vein.

A region in the right atrium of the heart that sets the rate and timing at which all cardiac muscle cells contract; the pacemaker.

It is located in the wall of the right atrium, near where the superior vena cava enters the heart.

The rhythmic bulging of the artery walls with each heartbeat.

AA circulatory system consisting of separate pulmonary and systemic cicuits, in which blood passes through the heart after completing each circuit.

An oxygen-storing pigmented protein in muscle cells. It is typically found in diving mammals.

An iron-containing protein in red blood cells that reverisbly binds oxygen. It is found within the red blood cells and allows for each red blood cell to hold 4 molecules of O2.

The uptake of molecular oxygen from the environment and the discharge of carbon dioxide to the environment.

(1) A heart chamber that pumps blood out of the heart.

(2) A space in the bertebrate brain, filled with cerebrospinal fluid.

A breathing system in which air is forced into the lungs.

The activated form of the blood-clotting protein fibrinogen. Fibrin aggregates into threads that form the fabric of the clot.

A hissing sound that most often results from blood squirting backward through a leaky valve in the heart.

The branch of the circulatory system that supplies the lungs.

(1) A sheet of muscle that forms the bottom wall of the thoracic cavity in mammals. Contraction of the diaphragm pulls air into the lungs.

(2) A dome-shaped rubber cup fitted into the upper portion of the vagina before sexual intercourse. It serves as a physical barrier to the passage of sperm into the uterus.

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.

The portion of the respiratory tract containing the vocal cords; also called the voice box.

The branch of the circulatory system that supplies all body organs except those involved in gas exchange.

An organ located along a lymph vessel. Lymph nodes filter lymph and contain cells that attack vircuses and bacteria.

(1) In animals, a vessel that carries blood toward the heart.

(2) In plants, a vascular bundle in a leaf.

A vessel that conveys blood between an artery and a capillary bed.

A disorder in which blood pressure remains abnormally high (high blood pressure).

The colorless fluid, derived from interstitial fluid, in the lymphatic system of vertebrates.

A vessel that carries blood away from the heart to organs throughout the body.

Any relatively unspecialized cell that can produce, during a single division, one identical daughter cell and one more specialized daughter cell that can undergo further differentiation.

A region of specialized heart muscle tissue between the left and right atria where electrical impulses are delayed for about 0.1 second before spreading to both ventricles and causing them to contract.

A particle in the blood made up of cholesterol and other lipids surrounded by a single layer of phospholipids in which proteins are embedded. LDL carries more cholesterol than a related lipoprotein, HDL, and high LDL levels in blood correlate with the deposition of cholesterol in arterial plaques.

A cardiovascular disease in which fatty deposits called plaques develop in the inner walls of the arteries, obstructing the arteries and causing them to harden.

The volume of air a mammal inhales and exhales with each breath.

• A particle in the blood made up of cholesterol and other lipids surrounded by a single layer of phospholipids in which proteins are embedded. HDL carries less cholesterol than a related lipoprotein, LDL, and high HDL levels in the blood may be correlated with the reduction of the deposition of cholesterol.
• "Good cholesterol"

The death of nervous tissue in the brain, usually resulting from rupture or blockage of arteries in the head.

A fine branch of the bronchi that transports air to alveoli.

A system of vessels and nodes, separate from the circulatory system, that returns fluid, proteins, and cells to the blood.

A circulatory system consisting of a single pump and circuit, in which blood passes from the sites of gas exchange to the rest of the body before returning to the heart.

An infolded respiratory surface of a terrestrial vertebrate, land snail, or spider that connects to the atmosphere by narrow tubes.

A protein that transports oxygen in blood or hemolymph. Respiratory pigments circulate with the blood or hemolymph and are often contained within specialized cells. The pigments greatly increase the amount of O2 that can be carrier in the cirulatory fluid.

A microscopic blood vessel that penetrates the tissues and consists of a single layer of endothelial cells that allows exchange between the blood and interstital fluid.

The liquid matrix of blood in which the cells are suspended.

A blood cell that functions in fighting infections; also called a white blood cell.

A blood cell that contains hemoglobin, which transports oxygen; also called a red blood cell.

A network of capillaries in a tissue or organ.

A brain center that directs the activity of organs involved in breathing.

One of a pair of breathing tubes that branch from the trachea into the lungs.

The ventilation of the lungs through alternating inhalation and exhalation.

A branch of the circulatory system in many amphibians that supplies the lungs and skin.

The pressure exerted by a particular gas in a mixture of gases (for instance, the pressure exerted by oxygen in air).

A breathing system in which air is pulled into the lungs.

An increase in the diameter of blood vessels caused by relaxation of smooth muscles in the vessel walls.

The volume of blood pumped per minute by each ventricle of the heart.

A record of the electrical impulses that travel through heart muscle during the cardiac cycle.

The exchange of a substance of heat between two fluids flowing in opposite directions.

For example, blood in a fish gill flows in the opposite direction of water passing over the gill, maximizing diffusion of oxygen into and carbon dioxide out of the blood.

A circulatory system in which blood is confined to vessels and is kept separate from the interstitial fluid.

The simple squamous layers of cells lining the lumen of blood vessels.

The stage of the cardiac cycle in which a heart chamber is relaxed and fills with blood.

A valve located at each exit of the heart, where the aorta leaves the left ventricle and the pulmonary artery leaves the right ventricle.

A pinched-off cytoplasmic fragment of a specialized bone marrow cell. Platelets circulate in the blood and are important in blood clotting.

A fibrin-containing clot that forms in a blood vessel and blocks the flow of blood.

The volume of blood pumped by a heart venticle in a single contraction.

A hormone that stimulates the production of erythrocytes. It is secreted by the kidney when body tissues do not receive enough oxygen.

The maximum volume of air that a mammal can inhale and exhale with each breath.

One of a pair of bands of elastic tissue in the larynx. Air rushing past the tensed vocal cord makes them vibrate, producing sounds.

The frequency of heart contraction.

Blood pressure in the arteries during contraction of the ventricles.

The amount of air that remains in the lungs after forceful exhalation.

The flow of air or water over a respiratory surface.

The portion of the respiratory tract that passes from the larynx to the bronchi; also called the windpipe.

A chamber of the vertebrate heart that receives blood from the veins and transfers blood to a ventricle.

A peptide produced by a blood vessel's endothelium that causes the vessel to constrict.

A heart valve located between each atrium and ventricle that prevents a backflow of blood when the ventricle contracts.

A lower of the affinity of hemoglobin for oxygen, caused by a drop in pH. It facilitates the release of oxygen from hemoglobin in the vicinity of active tissues. The lowering of the pH is brought on by an increase in the concentration of CO2.

(plural, alveoli) One of the dead-end, multilobed air sacs where gas exchange occurs in a mammalian lung.

A closed circulatory system with a heart and branching network of arteries, capillaries, and veins. The system is characteristic of vertebrates.

The blood pressure in the arteries when the ventricles are relaxed.

A substance secreted by alveoli that decreases surface tension in the fluid that coats the alveoli.

The stage of the cardiac cycle in which a heart chamber contracts and pumps blood.

The damage or death of cardiac muscle tissue resulting from prolonged blockage of one or more coronary arteries.