Nervous Control Of The Heart

Question 1

What is the benefit when the sympathetic system increases heart rate?

Answer 1

Greater cardiac output (more blood = more oxygen etc.)

Question 2

What is the benefit when the sympathetic system increases blood pressure?

Answer 2

Speeds up flow of blood and so oxygen and nutrients supply gets where it needs to quicker. Therefore energy is produced faster.

Question 3

What is the benefit when the sympathetic system secretes adrenaline and noradrenaline?

Answer 3

Fight or flight response. For example:

• Pupil dilation (so you can take in more light to see more clearly).

• It causes release of blood sugar (can then be carried to muscle cells to help produce energy).

Question 4

What is the benefit when the sympathetic system increases contractile force of cardiac muscle?

Answer 4

It increases stroke volume (amount of blood ejected from the heart each beat) which in turn increases blood flow.

Question 5

What is the benefit when the sympathetic system stimulates vasoconstriction and vasodilation?

Answer 5

It redirects blood flow and contributes to thermoregulation.

Question 6

What 4 things does the parasympathetic system do?

Answer 6

• Decreases heart rate to resting level.

• Decreases blood pressure to resting level.

• Decreases cardiac output to resting level.

• Will also re-direct blood flow and adjust thermoregulation.

Question 7

What are the benefits of the parasympathetic system?

Answer 7

Reduces the amount of time that we spend in this stressful state as soon as possible.

This helps to avoid the symptoms of chronic symptoms of chronic stress (e.g. diabetes, arterial hardening, depression, etc.).