Regulation Of Heart Rate

Question 1

How does heart rate increase?

Answer 1

The heart is controlled by the cardiac control centre in the medulla, sympathetic nerve impulses increase being sent to the SAN, whereas there is a decrease in parasympathetic nerve impulses. This happens via a release of Adrenaline/Noradrenaline

Question 2

How does heart rate decrease?

Answer 2

Parasympathetic nerve impulses increase being sent to the SAN and there is a decrease in sympathetic nerve impulses this is done by the vagus nerve and happens via a release of Acetylcholine

Question 3

How do chemoreceptors increase heart rate?

Answer 3

When exercise occurs CO2 levels in the blood increase, chemo receptors, detect this and send a message to the cardiac control centre, and increase sympathetic impulse to the SAN causes the heart rate to increase, a decrease in parasympathetic impulses to SAN causes the heart rate to increase

Question 4

How do proprioreceptors increase heart rate?

Answer 4

When there is an increase in skeletal movement proprioreceptors detect this and send a message to the cardiac control centre, an increase in sympathetic impulses to the SAN causes heart rate to increase, a decrease in Vegas impulses to SAN causes heart rate to increase

Question 5

How do baroreceptors increase heart rate?

Answer 5

Barorecpetors respond of walls caused by a change in blood pressure, they establish a setpoint for blood pressure, and if going above or below, this setpoint, send a signal to cardiac control centre. A decrease in arterial pressure below setpoint causes rate to increase, and if there is an increase in arterial pressure above setpoint, heart rate decreases

Question 6

What do baroreceptors do before exercise?

Answer 6

Baroreceptors increase the setpoint otherwise it would negatively affect performance

Question 7

What is anticipatory rise?

Answer 7

Anticipatory rise is the increase in heart rate before exercise due to release of adrenaline