Question 1

Which type of blood vessel is primarily responsible for material exchange between blood and tissues?

Accepted Answer

Capillaries

Question 2

Which capillary type is most likely found in the liver and bone marrow, allowing passage of large molecules and cells?

Accepted Answer

Sinusoidal capillaries

Question 3

Why is the velocity of blood flow lowest in capillaries?

Accepted Answer

Capillaries have the highest summed cross-sectional area

Question 4

Given Poiseuille’s Law $$R = \frac{8 L \eta}{\pi r^4$}$$, which factor has the greatest effect on vascular resistance?

Accepted Answer

Radius of the vessel (r)

Question 5

A patient with Raynaud’s disease experiences excessive vasoconstriction. Which receptor is most likely involved?

Accepted Answer

⍺1-receptors

Question 6

Which hormone decreases blood volume and pressure by increasing glomerular filtration rate and inhibiting renin, aldosterone, and ADH?

Accepted Answer

Atrial Natriuretic Peptide (ANP)

Question 7

What is the main mechanism by which oxygen and carbon dioxide cross capillary walls?

Accepted Answer

Diffusion through the lipid membrane

Question 8

Calculate the net pressure at the arterial end of a capillary given hydrostatic pressure $$P_{HA} = 32 mm Hg $$and colloid osmotic pressure $$\pi = 25 mm Hg.$$

Accepted Answer

$$7 mm Hg$$

Question 9

Which process describes fluid moving out of the capillary into the interstitial space?

Accepted Answer

Filtration

Question 10

If blood volume decreases due to dehydration, which compensatory mechanism is NOT activated?

Accepted Answer

Increased glomerular filtration rate

Question 11

Which equation correctly relates blood flow velocity ($$V$$), flow rate ($$Q$$), and cross-sectional area ($$A$$)?

Accepted Answer

$$V = \frac{Q}{A}$$

Question 12

Which of the following is a local (paracrine) signal that causes vasodilation in response to increased tissue metabolism?

Accepted Answer

Nitric oxide (NO)

Question 13

During sympathetic stimulation, which effect is seen in arterioles supplying skeletal muscle?

Accepted Answer

Dilation via β2-receptors

Question 14

Which of the following best describes the effect of PKG activation in vascular smooth muscle cells?

Accepted Answer

Decreases intracellular calcium, leading to relaxation

Question 15

Which of the following is NOT a determinant of mean arterial blood pressure?

Accepted Answer

Blood glucose concentration

Question 16

A patient receives an intravenous infusion of fluids, increasing blood volume. What is the expected effect on mean arterial pressure?

Accepted Answer

Mean arterial pressure increases

Question 17

Which hormone is released from the adrenal gland and increases sodium reabsorption in the kidney?

Accepted Answer

Aldosterone

Question 18

Which mechanism is responsible for the movement of water from the interstitial space into the capillary?

Accepted Answer

Colloid osmotic pressure

Question 19

Which of the following would most likely increase systemic vascular resistance?

Accepted Answer

Vasoconstriction of arterioles

Question 20

Which of the following is a consequence of net filtration exceeding net absorption in capillaries?

Accepted Answer

Edema formation

Microcirculation and Regulation of Blood Flow and Pressure

Study Guide - Practice Questions

Study Guide - Flashcards