| A | B |
|---|
| artery | blood vessel that carries blood away from the heart |
| vein | blood vessel that carries blood into the heart |
| pulse | change in the diameter of arteries following heart contractions |
| autonomic nervous system | part of the nervous system that controls the motor nerves that maintain equilibrium - regulates diameter of arterioles. Not under conscious control. |
| vasoconstriction | narrowing of blood vessels, allowing less blood to tissues |
| vasodilation | widening of blood vessels, allowing more blood to tissues |
| capillaries | blood vessels that connect arteries and veins; the site of gas and fluid exchange between blood and cells |
| septum | wall of muscle that separates the right and left sides of heart |
| pulmonary circulatory system | the system of blood vessels between the heart and lungs |
| systemic circulatory system | the system of blood vessels between the lungs and body |
| atrium (atria) | a thin-walled chamber of the heart that receives blood from veins |
| ventricle | a muscular, thick-walled chamber of the heart that delivers blood to arteries |
| AV valve | the valve between the atrium and ventricle to prevent backflow of blood |
| semilunar valve | the valve between the ventricle and artery to prevent backflow |
| aorta | the largest artery in the body - carries oxygenated blood from the heart to body tissues |
| coronary artery | an artery that supplies cardiac muscle in the heart with oxygen and nutrients |
| SA node | the pacemaker of the heart - a small mass of nerves that stimulate heartbeat |
| AV node | a small mass of tissue in the right atrioventricular region that passes impulses from the SA node to the ventricles |
| Purkinje fibres | nerve fibres that branch out to the ventricles and carry electrical impulses to make the ventricles contract |
| parasympathetic nervous system | a division of the autonomic nervous system that returns the body to normal after stress |
| diastole | relaxation (dilation) of the heart; the atria fill with blood during diastole |
| systole | contraction of the heart; blood is pumped out of the ventricles |
| cardiac output | the amount of blood pumped out of the heart each minute (=stroke volume x heart rate) |
| stroke volume | the quantity of blood pumped out of the heart per beat |
| heart rate | the number of times the heart beats per minute |
| sphygmomanometer | a device used to measure blood pressure |
| thermoregulation | maintenance of body temperature within a range that allows cells to function |
| hypothalamus | region of the brain responsible for coordinating many nerve and hormone functions, including thermoregulation |
| extracellular fluid (ECF) | the fluid that occupies the space between cells and tissues |
| filtration | the selective movement of materials through capillary walls by a pressure gradient |
| lymph | the fluid found in lymph vessels that contains some proteins that have leaked through capillary walls |
| lymph node | mass of tissues that stores lymphocytes (white blood cells) and removes bacteria and foreign particles from lymph |
| lymphocyte | a white blood cell that produces antibodies |
| spleen | a lymphoid organ that acts as a reservoir for blood and filtering site for lymph |
| thymus gland | a lymphoid organ in which T cells mature |
