circulation of blood

To recognise the basic anatomy and the function of the major components of the CVS, including the heart (including valves), arteries, veins and microcirculation.

the circulatory system has a parallel arrangement of vessels system which allows for two main things

metabolic demands of tissues (can inc blood flow to muscle and decrease to abdomen during exercise)

allows for independent regulation of blood flow to different organs (think physics batteries)

there are 2 MAIN types of valve and there are two per type of each valve

semilunar valves (located between the ventricles and great vessels

these valves are less flimsy than atrioventricular valves and so they do not have the need for papillary muscles/chordae pectiniae instead once blood has flown through them because the heart cannot pump ALL the blood out and up the blood vessels in one beat some blood falls back down and closes the valves and this itself prevents the back-flow of blood

the two types of semilunar valves are as follows…

aortic valve - between the left ventricle and aorta

pulmonary valve - between the right ventricle and pulmonary

atrioventricular valves (located between the atria and ventricles)

the two types of atriaventricular valves are as follows…

mitral - (bicuspid) = found between the left atria and ventricle

tricuspid - found between the right atria and ventricle

these valves contain chordae tentinae which are attached to pappillary muscles (found in ventricles) and the papillary muscles contract JUST before contraction occurs which tightens the chordae pentiniae which makes sure the valve doesn’t ‘’go back in on itself’’ the blood itself is the thing that shuts the valve the chordae pentiniae and papillary muscles just act to ensure regurgitation doesn't occur