the structure of the heart Flashcards Preview

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Flashcards in the structure of the heart Deck (21):

where is the heart located?

thoracic cavity behind the sternum (breast bone).


which side of the heart pumps which type of blood?

left side - oxygenated from lungs right side - deoxygenated from body


what are the two chambers made of?

atrium - thin-walled and elastic - stretches as it collects blood

ventricles - much thicker muscular wall as has to contract strongly to pump blood either to lungs or rest of body.


why is the heart made of two separate pumps?

blood has to fall through tiny capillaries in the lungs, in order to present a large SA for the exchange of gases - a very large drop in pressure - 1 pump = slow circulation


why is it essential to keep oxygenated blood to the left side and de-oxygenated blood to the right?

would result in partially oxygenated blood reaching the tissues and the lungs - reduced diffusion in the lungs, limiting the rate of oxygen uptake - supply of oxygen to tissues would be inadequate 


why does the left ventricle have a thicker muscular wall?

to contract and create enough pressure to pump blood to rest of the body.


both sides of the heart...

pump at the same time - both atria and ventricles contract together, pumping the same volume of blood.


what is the role of a valve?

prevent backflow of blood into atria when ventricles contract


name the two valves in the upper chamber

left atrioventricular (bicuspid)/mitral valve right atrioventricular (tricuspid) valve


what is the role of a ventricle?

pumps blood away from the heart and into the arteries


what is the role of a vein?

carry blood to the and atria into the heart


vessels connecting the heart to the lungs are called...

pulmonary vessels


vena cava

connected to the right atrium and brings deoxygenated blood back from the tissues of the body (except the lungs).


pulmonary artery

connected to the right ventricle and carries deoxygenated blood to the lungs, where its oxygen is replenished and cO2 is removed.


pulmonary vein

connected to the left atrium and brings back oxygenated blood back from the lungs.



connected to the left ventricle and carries oxygenated blood to the body (except the lungs).


what are the coronary arteries?

hearts own supply of oxygen - branches off the aorta.


what happens if the coronary arteries are blocked e.g. blood clot?

leads to myocardial infarction or heart attack - an area of muscle deprived of blood/oxygen - muscle cells in this region unable to aerobically respire and so die


what is the septum?

the partition separating the two chambers


name the two valves in the lower chamber

semi-lunar valves


diagram of heart