Cardiovascular System

Question 1

What does the cardiovascular system provide? (3)

Answer 1

1. O2
2. Nutrients
3. Water

Question 2

What does the cardiovascular system move? (6)

Answer 2

1. Immune cells
2. Antibodies
3. Clotting proteins
4. Hormones
5. Bodily wastes
6. Red blood cells (CO2)

Question 3

What are the 3 components of the CVS (cardiovascular system)? (3)

Answer 3

1. Heart as pumps
2. Blood vessels
3. Blood circulation in CVS

Question 4

What does the inferior vena cava carry?

Answer 4

deoxygenated blood from body to heart

Question 5

What does the superior vena cava carry?

Answer 5

deoxygenated blood from brain to heart

Question 6

What does the pulmonary artery carry?

Answer 6

deoxygenated blood from heart to lungs

Question 7

What does the pulmonary vein carry?

Answer 7

oxygenated blood from the lungs to the heart

Question 8

what does the aorta carry?

Answer 8

oxygenated blood from the heart to the body (systemic circuit)

Question 9

what is the circuit involving the heart and lungs?

Answer 9

pulmonary circuit

Question 10

what is the circuit involving the heart and the rest of the body?

Answer 10

systemic circuit

Question 11

what % of cardiac muscle cells are autorythmic cells?

Answer 11

1%

Question 12

what is the node thats responsible for initiating a heartbeat (autorythmic cells)

Answer 12

sino-atrial node

Question 13

What is the node responsible for connecting the electrical systems of the atrium and ventricle?

Answer 13

atrio-ventricular node

Question 14

what are the specialised nerve cells that transmit electrical signals to the heart’s ventricles, causing them to contract and pump blood throughout the body.

Answer 14

purkinje fibres

Question 15

Describe the stages of the conducting system (5)

Answer 15

1. SA node activated (depolarises)
2. Electrical activity goes rapidly to AV node via inter-nodal pathways
3. Activation signal (depolarisation) spreads more slowly across atria
4. Signal (depolarisation) moves rapidly through purkinje fibres to apex of heart
5. Signal (depolarisation) wave spreads upward from apex

Question 16

Describe the trace of a human electrocardiogram (3)

Answer 16

1. P wave - trace starts
2. QRS wave - middle sharp and relatively large peak
3. T wave - final gentle bump

Question 17

What does the P wave represent on the human electrocardiogram?

Answer 17

SA node activation

Question 17

What does the QRS wave represent on the human electrocardiogram?

Answer 17

Activation of AV node and purkinje fibres

Question 18

What does the T wave represent on the human electrocardiogram?

Answer 18

Ventricle diastole

Question 19

What represents a cardiac cycle on the human electrocardiogram?

Answer 19

From the peak of one P wave to the next P wave

Question 20

Describe the blood flow system (5)

Answer 20

1. Diastole - all chambers relaxed, ventricles fill passively
2. Atrial systole - contraction forces small amount of additional blood into ventricle via AV valves
3. Ventricular depolarisation (purkinje fibres) - 1st phase contraction, AV valves closed, not enough pressure to open semilunar valves
4. Ventricular ejection - ventricle pressure rises enough, semilunar valves open, blood ejected
5. Ventricular diastole - pressure falls and blood flows back into cusps of semilunar valves, closing them

Question 21

What is the equation for cardiac output?

Answer 21

HR x SV = CO (l/m)
Heart rate x systolic volume = cardiac output (litres/minute)

Question 22

What is the equation for stroke volume?

Answer 22

EDV - ESV = SV
End diastolic volume - end systolic volume = stroke volume
(volume of blood pumped per contraction)

Question 23

What is the cardiac output % of the digestive tract and liver at rest?

Answer 23

27%

Question 24

What is the cardiac output % of the muscles at rest?

Answer 24

21%

Question 25

What is the cardiac output % of the kidneys at rest?

Answer 25

20%

Question 26

What is the % cardiac output muscles can receive during exercise?

Answer 26

85%