Circulatory System-physiology - section 1

Question 1

If the cross-sectional area is doubled, how does the velocity within a vessel change?

Answer 1

Velocity is cut in half. (V=Q/A)

Question 2

If the radius of a vessel is doubled, how does flow of blood change?

Answer 2

Resistance decrease by factor of 16, and therefore flow increases by factor of 16.

Question 3

Which has more resistance: vessels in series or in parallel?

Answer 3

Vessels in series has greater total resistance.

Question 4

If you’re able to hear bruit of a vessels using a stethoscope, what is the Reynolds number?

Answer 4

greater than 2000

Question 5

What factors does the Reynold number take into account?

Answer 5

Velocity, Cross-sectional area, density, and viscosity

Question 6

When velocity is 1, cross sectional area is __2__, density is 3, and/or viscosity is 4, blood flow is more turbulent.

Answer 6

1. high,
2. large
3. heavy
4. low

Question 7

Which vessel types have greater compliance?

Answer 7

Veins

Question 8

Where are you likely to see the greatest drop in pressure in the circulatory system?

Answer 8

across arterioles.

Question 9

A patient’s BP is 120/80, what is the mean pressure?

Answer 9

93.3

Question 10

If arterial compliance is decreased, how does the pulse pressure change?

Answer 10

Pulse pressure increases.

Question 11

How does aortic stenosis affect mean arterial pressure?

Answer 11

Decrease.