Chapter 15: Alterations in Blood Flow

Chapter 15: Alterations in Blood Flow

Complete Chapter Questions With Answers

Sample Questions Are Posted Below

MULTIPLE CHOICE

1. Which vessel normally demonstrates the most rapid blood flow?

ANS:  D

The vena cava has the most rapid rate of flow. Arterioles don’t offer the most rapid blood flow. Capillaries are composed of a single thickness of endothelial cells attached to a protein network called the basement membrane and don’t offer the most rapid blood flow. A venule begins where the arteriole ends and doesn’t offer the most rapid blood flow.

REF:   Pg. 316

2. The movement of blood through the vascular system is opposed by the force of

ANS:  D

The movement of blood through the vascular system is opposed by the force of resistance. Three determinants of resistance are vessel length, vessel radius, and blood viscosity. Viscosity is the thickness of fluid and has an effect on resistance. The length of the vessel does have an effect on the resistance. Vessel radius has an effect on resistance.

REF:   Pg. 314

3. Which causes vasoconstriction?

ANS:  A

The release of norepinephrine results in arterial vasoconstriction via receptors located on the vascular smooth muscle walls. Calcium channel blockers produce vasodilation by interfering with calcium intake into the vascular smooth muscle cells. a-Adrenergic antagonists do not cause vasoconstriction. Acetylcholine does not have an effect on vasoconstriction.

REF:   Pg. 318

4. When systemic vascular resistance is decreased, blood flow

ANS:  B

When SVR is pathologically decreased, the blood is spread over a larger area and blood flow slows dramatically. Individual organs, such as the kidney and brain, may not obtain sufficient blood flow to meet metabolic needs. Blood flow decreases in response to decreases in vascular resistance. When SVR is pathologically decreased, the blood is spread over a larger area and blood flow slows dramatically. Individual organs, such as the kidney and brain, may not obtain sufficient blood flow to meet metabolic needs. Blood flow is not diverted to the extremities when systemic vascular resistance is decreased. However, the vital organs may not have sufficient blood flow to maintain metabolic needs.

REF:   Pg. 315