cardiovascular system

Question 1

what factors affect stroke volume?

Answer 1

• venous return
• how far the ventricles will stretch
• the pressure of the arteries leading from the heart
• ejection fraction

Question 2

what is Starling’s law

Answer 2

during exercise, venous return increases and therefore cardiac output increases.

Question 3

what is venous return

Answer 3

the amount of blood returning to the heart

Question 4

what is cardiac output

Answer 4

the amout of blood pumped around the heart per minute
stroke volume x heart rate = cardiac output

Question 5

what is cardiovascular drift

Answer 5

when there is an increase of heart rate after 10 minutes of steady state exercise. This is due to stroke volume decreasing, blood becoming more viscous. to maintain cardiac output, heart rate must increase.

Question 6

what is bradycardia

Answer 6

hypertrophy of the myocardium meaning it gets bigger and stronger. as a result resting HR decreases below 60bpm.

Question 7

what does the left hand side of the heart do

Answer 7

it is responsible for pumping oxygenated blood around the body

Question 8

how does the heart conduction system work

Answer 8

• heart generates its own electrical impulse at the sino-atrial node
• impulse spreads through cardiac tissue in the atria
• this causes contraction in the atria
• the impulse carries onto the atrio-ventricular node
• the action potential moves into the Bundle of His and spreads throughout the Purkinje fibres, causing the ventricles to contract