Pressure Gradients, Blood Flow & Peripheral Resistance

Question 1

Describe arteries.

Answer 1

• low resistance vessels conducting blood to various organs with little loss in pressure
• acts as pressure reservoirs for maintaining blood flow between contractions

Question 2

Describe arterioles.

Answer 2

• major sites of resistance to blood flow
• responsible for flow distribution
• regulation of blood pressure

Question 3

Describe capillaries.

Answer 3

• site of exchange between blood & tissues

Question 4

Describe veins.

Answer 4

• low resistance vessels for blood to flow back to heart

- capacity for blood is adjusted to facilitate flow

Question 5

What is flow rate?

Answer 5

pressure between two points and resistance to flow

Question 6

What is the force equation?

Answer 6

F = pressure gradient/resistance

Question 7

What are the three factors that affect resistance to blood flow?

Answer 7

• viscosity
• vessel length
• vessel radius

Question 8

What is the Poiseuille equation?

Answer 8

Flow rate = pi x pressure gradient x radius of vessel^4/8 x viscosity x length of vessel

Question 9

What are two factors responsible for vascular tone?

Answer 9

1) myogenic activity

2) sympathetic activity

Question 10

What is the systole phase of the cardiac cycle?

Answer 10

contraction and emptying

Question 11

what is the diastole phase?

Answer 11

relaxation and filling.

Question 12

What are the 5 phases of the cardiac cycle?

Answer 12

1) passive filling during ventricular and atrial diastole
2) atrial contraction
3) isovolumetric ventricular contraction
4) ventricular ejection
5) isovolumetric ventricular relaxation

Question 13

What is pulse pressure?

Answer 13

Difference between systolic and diastolic blood pressure.