circulatory system revision Flashcards
what is systole
the contraction phase of the atria and ventricles.
what is systole measured in
mmHg and give the upper reading of BP
Aorta is
a major artery that carries oxygenated blood out of the left ventricle and through the systemic circulatory system
Capillaries
microscopically thin blood vessels which are fed by arterioles and are semi permeable allowing O2 and CO2 to pass through their walls
valves
found in the heart between the top and bottom chambers . it prevents regurgitation of blood.
skeletal pump
during exercise the muscles surrounding the veins expand and contract, pressing on the veins and causing a pumping effect to maintain venous return
pulmonary
its an artery that takes deoxygenated blood from the right ventricle to the lungs to pick up O2 and get rid of CO2
cardiac
is a type of muscle that forms the heart. it receives its own nourishment via the coronary arteries
cardiac output
amount of blood poured out by the left ventricle each minute . at rest usually 5 litres/minute.
veins
blood has to travel against gravity and back up to the right atrium. thinner walls and are less elastic.
anaemia
a condition where a person has a shortage of red blood cells and constantly feels tired weal and reathless
red blood cells
bi concave disc shape, contain iron have a life cycle of about 120 days and produce in bone marrow which contain haemoglobin
white blood cell
produced in bone marrow lymph tissue and spleen they have no special shape
platelets
responsible for blood clotting
diastolic pressure
measure of the blood pressure against the artery walls during the relaxation phase of the hearts pumping action
