Author Question: During exercise, cardiac output increases dramatically, but mean arterial blood pressure rises very ... (Read 53 times)

viki

  • Hero Member
  • *****
  • Posts: 525
During exercise, cardiac output increases dramatically, but mean arterial blood pressure rises very little. Why is this so?
 
  a. Venules constrict, increasing vascular re-sistance.
  b. Arterioles dilate, decreasing vascular ca-pacity.
  c. Arterioles constrict, increasing vascular resistance.
  d. Muscle vessels dilate, increasing vascular capacity.

Question 2

Mean arterial blood pressure can be regulated by changing which of the following? 1. Capacity of the circulatory system 2. Effective volume of circulating blood 3. Tone of the capacitance vessels (veins)
 
  a. 1 and 2 only
  b. 2 only
  c. 1, 2, and 3
  d. 3 only



chem1s3

  • Sr. Member
  • ****
  • Posts: 320
Answer to Question 1

ANS: D
For example, when exercising, the circulating blood volume undergoes a relative increase, but blood pressure remains near normal. This is because the skeletal muscle vascular beds dilate, causing a large increase in system capacity.

Answer to Question 2

ANS: C
All else being constant, mean arterial pressure is directly related to the volume of blood in the vascular system and inversely related to its capacity. A change in the tone of the capacitance vessels alters their capacity.
Mean arterial pressure = volume/capacity.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

The human body produces and destroys 15 million blood cells every second.

Did you know?

More than 34,000 trademarked medication names and more than 10,000 generic medication names are in use in the United States.

Did you know?

ACTH levels are normally highest in the early morning (between 6 and 8 A.M.) and lowest in the evening (between 6 and 11 P.M.). Therefore, a doctor who suspects abnormal levels looks for low ACTH in the morning and high ACTH in the evening.

Did you know?

GI conditions that will keep you out of the U.S. armed services include ulcers, varices, fistulas, esophagitis, gastritis, congenital abnormalities, inflammatory bowel disease, enteritis, colitis, proctitis, duodenal diverticula, malabsorption syndromes, hepatitis, cirrhosis, cysts, abscesses, pancreatitis, polyps, certain hemorrhoids, splenomegaly, hernias, recent abdominal surgery, GI bypass or stomach stapling, and artificial GI openings.

Did you know?

Blood is approximately twice as thick as water because of the cells and other components found in it.

For a complete list of videos, visit our video library