Central Nervous Control of Circulation

Question 1

Which set of nerves originating from the vertebrae innervate all the vasculature of the body.

Answer 1

T1-L2 Sympathetic Nerves

Question 2

Which nerves originating from the vertebrae innervate the heart?

Answer 2

T1-T5 Sympathetic Nerves

Question 3

Which nerve supplies the parasympathetic innervation of the heart?

Answer 3

Vagus nerve

Question 4

What does sympathetic innervation of heart control vs parasympathetic innervation?

Answer 4

sympathetic: rate of contraction and force of contraction

parasympathetic of nodal regions : heart rate

Question 5

Which 3 variables affect blood pressure?

what is the equation for BP

Answer 5

• Heart rate
• Stroke Volume
• Total peripheral resistance

Therefore BP = HR X SV X Rtotal peripheral

Question 6

where are the baroreceptors located?

Answer 6

Corotid Sinus and Aortic arch

Question 7

what is the name of the parasympathetic nerve from corotid sinus?

Answer 7

Glossopharyngeal

Question 8

Name the nerve from the aortic arch baroreceptor

Answer 8

Vagus nerve

Question 9

What is the compensatory mechanism (3 steps) as a result of low blood volume (due to blood pooling) ?

Answer 9

• vasoconstriction of veins (so increased venous return)
• increase in Heart rate
• increase in force of contraction

Question 10

How does the Valsalva Manoeuver moniter Baroreceptor Reflex?

Answer 10

During exhalation, the venous return decreases bcas compression of rib cage on to heart

so Hr increases to maintain BP

Question 11

what does stimulation of ventricular mechanoreceptors do?

Answer 11

They ellicit vasodilation and bradycardia so heart doesnt have to overwork