response to sport (cardiac cycle)

Question 1

to meet demands of exercise the cardiac cycle has to

Answer 1

heart rate increases
blood fills artia and ventricles
blood pressure rises

Question 2

vasodilation

Answer 2

blood rushes to active muscles , increase dilation of artericles . increase diameter of blood vessels

Question 3

vasoconstriction

Answer 3

shorters the diameter of blood vessels by contraction of involuntary muscles fibres.

Question 4

what happens in the anticipatory increase in heart rate

Answer 4

heart rate can change due to neurotransmitters , such as adrenaline and noradrenaline , being released from the brain. before exercise, heart rate increases and blood flow begins to supply oxygen and nutrients to the working muscles

Question 5

what is cardiac output

Answer 5

volume of blood pumped out in one minute

Question 6

what is calculation for cardiac output

Answer 6

heart rate multipled by stroke volume

Question 7

what is stroke volume

Answer 7

amount of blood pumped out of left ventricle in one contraction. exercise increases it and then levels off until exercise is finished

Question 8

explain heart rate

Answer 8

heart rate changes according to the bodies needs , it increases during exercise to deliver oxygen and remove waste products

Question 9

what does adrenaline do

Answer 9

makes heart beat faster. Once exercise has started, there is an increase in carbon dioxide and lactic acid in the body which is detected by chemoreceptors. ​

Question 10

what is heart rate controlled by

Answer 10

the sinoatrial node . heart rate goes up or down when San receives information via nerves that link the SAN with the cardiovascular centre in the brain

Question 11

how does the heart adapt to exercise

Answer 11

1. the sympathetic nerve speeds up the heart - synapses at end of nerve produce a hormone called noradrenaline
2. the vagus nerve slows down heart- synapses at end of nerve produce a hormone called acetylcholine

Question 12

How many litres of blood are circulated each minute at rest?

Answer 12

5 litres

Question 13

What is the benefit of increased cardiac output?

Answer 13

More blood can be transported to working muscle and therefore more oxygen

Question 14

What is Starlings Law Theory?

Answer 14

Starlings Law Theory states that stroke volume increases in response to an increase in blood volume filling the heart. This stretches the walls, causing the cardiac muscle to contract forcefully