Effect of Exercise on Heart Rate

Question 1

how many times does our heart beat at rest?

Answer 1

around 70 times a minute

Question 2

why does our heart rate increase?

Answer 2

so that more blood can travel to the muscle

Question 3

what part of the brain controls change in heart rate?

Answer 3

the medulla

Question 4

the effect of exercise on heart rate?

Answer 4

• when exercise starts the muscles produce more carbon dioxide in aerobic respiration
• sensors in the aorta and carotid artery detect this increase
• they send nerve impulses to the medulla
• the medulla responds by sending nerve impulses along the accelerator nerve
• the accelerator nerve increases the heart rate
• more blood is supplied to the muscles to meet the demands of increased aerobic respiration
• the decelerator nerve sends electrical impulses to decrease heart rate at rest

Question 5

what hormone increases our heart rate when we are stressed or angry?

Answer 5

adrenaline