Cardiovascular physiology III

Question 1

What are blood vessels and the three different types?

Answer 1

All are made from different tissue, but lines with endothelium tissue which acts as a barrier between blood and vessels

1) Artery: smooth muscle, elastic, important for maintaining blood pressure
2) Capillaries: no smooth muscle, exchange vessels
3) Veins: smooth muscle which allows capacity change and therefore controls stroke volume

Question 2

Where does blood go from the right and left sides of the heart?

Answer 2

Right side: blood –> lungs

Left side: blood –> body

Question 3

How does blood get from arteries to veins?

Answer 3

1) Artery
2) Ateriole (smooth muscle)
3) Blood diffusion (capillary)
4) Vein/heart

Question 4

How is blood pressure generated?

Answer 4

Through ventricular contraction

1) Contraction: ventricle contracts, semilunar valves open, aorta/arteries expand and store pressure in elastic walls which allows blood to travel out of the ventricle into arteries due to low pressure
2) Relaxation: isovolumic ventricular relaxation, semilunar valve shuts, elastic recoil of arteries increases pressure in the arteriole which forces blood forwards

Question 5

What are aortic aneurysms?

Answer 5

This happens when the stretch does not return to the aorta, it is treated with mesh

Question 6

What is mean arterial blood pressure?

Answer 6

This is the driving force for blood flow, determined by blood volume, the pump, resistance of flow and distribution.

Question 7

How does pressure decrease?

Answer 7

Through the venus cycle:
Open - max pressure
Closed - resting pressure

Question 8

What do baroreceptors do?

Answer 8

Detect changes in blood pressure and respond immediately by sending signals to the medulla.

Question 9

What is the renin angiotensin aldosterone system?

Answer 9

This is part of the kidneys, renin is a hormone released when the arterial pressure is low
Renin produces angiotenin II to the blood which:
-Stimulates thirst
-Constricts blood vessels
-Increases sodium and water
-Increases blood volume and peripheral resistance

Question 10

What is local control?

Answer 10

Intrinsic autoregulation - enables changes in flow and keeps pressure constant

Question 11

What is active hypermia?

Answer 11

A decrease in O2 levels and increase in Co2 levels from working out

Question 12

What is flow autoregulation?

Answer 12

Increase flow of noradrenaline and lower blood pressure from stress