Blood Pressure Regulation

Answers to Questions on Blood Pressure Regulation:

1. Sensory receptors that detect increased pressure, by increased stretch in arterial walls.

2. In the carotid sinus, aortic arch, and other large arteries of the neck and thorax.

3. Increased blood pressure stretches arterial walls, stimulating the baroreceptors.  The result is an increase in sensory signals to the brain.

4. Get increased parasympathetic activity and decreased sympathetic activity.

5. Heart rate decreases and blood pressure decreases.

6. The vagus nerve (cranial nerve X).

7. By lowering cardiac output.

8. A sympathetic nerve fiber that innervates muscular arteries and arterioles.

9. High blood pressure decreases sympathetic activity, sympathetic impulses to vascular smooth muscle decreases and there is a vasodilation of the arteries.

10. When vasodilation occurs, there is an increase in arterial diameter, allowing more space for the blood to be in.  The result is less pressure on the walls of the arteries (lowered blood pressure).

11. Baroreceptors are not stimulated.  Get decreased impulses to the brain which increase sympathetic activity and decrease parasympathetic activity.

12. 1. Get increased heart rate and increased contractility leading to an increased blood pressure.  2. Get increased vasoconstriction  3. Get release of epinephrine and norepinephrine which enhance heart rate, contractility, and vasoconstriction leading to an increased blood pressure.

13. By increasing cardiac output.

14. Low blood pressure increases sympathetic activity, sympathetic impulses to vascular smooth muscle increases and there is a vasoconstriction of the arteries, causing the blood pressure to rise.

15. When vasoconstriction occurs, there is an decrease in arterial diameter, allowing less space for the blood to be in.  The result is more pressure on the walls of the arteries (increased blood pressure).

16.  Adrenal gland releases the hormones epinephrine and norepinephrine.

17. Hormones travel in the blood which takes more time than the release and action of neurotransmitters.