the heart

Question 1

what is the aorta?

Answer 1

an artery

Question 2

what is the vena cava?

Answer 2

a vein

Question 3

where does aorta take oxygenated blood? (4)

Answer 3

● right side

● head

● left side

● lower body

Question 4

where does pulmonary artery take deoxygenated blood? (2)

Answer 4

● right lung

● left lung

Question 5

where does pulmonary vein bring oxygenated blood from? (2)

Answer 5

● right lung

● left lung

Question 6

where does inferior vena cava bring deoxygenated blood from?

Answer 6

from lower body

Question 7

where does superior vena cava bring deoxygenated blood from?

Answer 7

from upper body

Question 8

what is the atrioventricular valve?

Answer 8

valve in between atrium and ventricle

Question 9

what is the semi lunar valve?

Answer 9

valve in between ventricle and artery

Question 10

draw a diagram of the human heart, including names of chambers, vessels and valves

Answer 10

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Question 11

what are the 3 parts of the cardiac cycle?

Answer 11

● diastole

● atrial systole

● ventricular systole

Question 12

what happens during a diastole? (5)

Answer 12

● all muscle relaxes

● av valve open

● sl valve closed

● blood flows into the atria

● pressure is highest in the arteries

Question 13

what happens during an atrial systole? (5)

Answer 13

● atrial muscle contracts

● av valve open

● sl valve closed

● blood flows into ventricle

● pressure highest in atrium

Question 14

what happens during a ventricular systole? (5)

Answer 14

● ventricular muscle contracts

● av valve closed (prevents back flow of blood into the atria)

● sl valve open

● blood flows into arteries (pulmonary artery, aorta)

● pressure highest in ventricle

Question 15

describe the pathway of blood in the heart (4)

Answer 15

● deoxygenated blood returns from body in vena cava (vein) and enters right atrium

● blood then passes via an atrio-ventricular valve into the right ventricle and, via semi lunar valve, into the pulmonary artery

● blood passes through lungs and returns to left atrium via the pulmonary vein

● blood passes through second atrio-ventricular valve into the left ventricle and then passes through the semi-lunar valve into the aorta where it is pumped around the whole body

Question 16

why is the left ventricle thicker? (2)

Answer 16

● has thicker, muscular walls than right ventricle

● as it needs to contract powerfully to pump blood around entire body

Question 17

when do semi-lunar valves open?

Answer 17

when pressure is higher in ventricles than arteries

Question 18

when do semi-lunar valves close? (2)

Answer 18

● when pressure is higher in arteries than ventricle

● to prevent back flow of blood from arteries to ventricle

Question 19

when do atrio-ventricular valves close? (2)

Answer 19

● when pressure is higher in ventricle than the atria

● to prevent back flow of blood from ventricle to atria

Question 20

when do atrio-ventricular valves open?

Answer 20

when pressure is higher in atria than ventricles

Question 21

what is cardiac output?

Answer 21

volume of blood pumped by left ventricle in 1 minute

Question 22

what is heart rate?

Answer 22

contraction of heart in a minute

Question 23

what is stroke volume?

Answer 23

volume of blood that leaves left ventricle per contraction (ventricular systole)

Question 24

what is the equation for cardiac output?

Answer 24

cardiac output(cm3min-1) = heart rate (bpm) x stroke volume (cm3)

Question 25

what is CHD? (3)

Answer 25

● coronary heart disease ● a type of CVD ● coronary arteries supply blood to the heart muscle itself

Question 26

where does CVD occur? (2)

Answer 26

● arteries ● higher blood pressure in arteries more likely to damage endothelium

Question 27

what are the risk factors of CHD? (3)

Answer 27

● increase in blood pressure - high salt diet (salt lowers water potential of blood plasma, higher pressure damages endothelium) ● increased blood fat levels - high fat level, sedentary lifestyle ● increased heart rate - nicotine / caffeine - leads to a higher blood pressure

Question 28

what is atherosclerosis? (7)

Answer 28

● the process of atheroma formation ● lumen of artery is narrowed due to build up of fatty deposits and cholesterol underneath endothelium of artery ● deposit is called an atheroma ● plaque forms and bulges into lumen of artery ● atheroma may cause reduced blood flow to heart muscle cells ● if blood vessel is completely blocked, the muscle cells get no oxygen and die ● this will cause a heart attack (myocardial infarction)

Question 29

what is thrombosis? (6)

Answer 29

● plaque may rupture ● trigger blood clotting over damaged area ● clot builds up very rapidly causing further blockage of artery ● known as a thrombus ● clot may break up, travel up blood stream and cause blockage elsewhere ● could lead to problems such as a stroke

Question 30

what is an aneurysm? (5)

Answer 30

● when artery blocked - blood flow through area restricted ● blood pressure builds up in front of blockage and presses on artery wall ● pressure causes wall to weaken and it starts to bulge outwards ● known as aneurysm ● vessel may rupture resulting in internal bleeding