Chapter 23

12) Which of the following statements regarding blood pressure is false? A) The higher number in a blood pressure reading measures the force of a heart contraction. B) High blood pressure can lead to an enlarged and weakened heart, increased risk of heart attack, stroke, and kidney failure. C) Normal blood pressure for adult humans is usually at or below 120/80. D) Hypertension is defined as persistent systolic pressure above 120 and/or diastolic above 80.

A

16) The liquid part of blood is called A) plasma. B) serum. C) interstitial fluid. D) water.

A

17) Which of the following statements about red blood cells is true? A) Red blood cells are shaped like biconcave disks. B) Red blood cells in adult humans have nuclei. C) Each red blood cell contains about 1 million molecules of hemoglobin. D) The main function of red blood cells is to carry nutrients.

A

3) In mammals, which of the following vessels transports oxygenated blood from the lung back to the heart? A) superior vena cava B) pulmonary artery C) pulmonary vein D) coronary artery

A

7) The main function of the AV node is to A) initiate the heartbeat. B) relay a signal for the ventricles to contract. C) relay the signal for the heart to contract from the right ventricle to the right atrium. D) set the rhythm of the heartbeat.

B

10) As blood moves away from the heart toward the tissues, the relative size of blood vessels ________, the blood pressure ________, and the velocity of blood flow ________. A) increases; decreases; decreases B) decreases; decreases; increases C) decreases; decreases; decreases D) decreases; increases;

C

11) Which of the following factors contributes to the flow of blood in veins? A) the diameter of capillaries B) skeletal muscle contractions C) blood pressure generated by the heart D) the number of red blood cells in venous blood

C

14) The diameter of a capillary is about the same as that of a(n) A) nerve. B) arteriole. C) venule. D) red blood cell.

C

15) One way that substances move between blood and interstitial fluid is by A) osmosis. B) alternatively breaking and regenerating membranes of cells lining capillaries. C) pressure‐driven flow through clefts between the epithelial cells of the capillary wall. D) active transport utilizing ATP.

C

2) Adaptation to terrestrial life involved major evolutionary changes. The change from gill breathing to lung breathing was accompanied by important changes in the A) association of blood and interstitial fluid. B) manufacture of blood cells. C) cardiovascular system. D) reproductive system.

C

4) Blood is pumped from the heart to the lungs by the A) left atrium. B) right atrium. C) right ventricle. D) left ventricle.

C

8) Myocardial infarction, also called a heart attack, A) actually causes no permanent damage to the heart. B) is caused by excessive blood pressure in the heart. C) is the damage or death of cardiac muscle tissue. D) is unrelated to cigarette smoking.

C

1) Which of the following is a function of the circulatory system? A) transporting nerve impulses throughout the body B) governing nutrient concentration in the blood C) mounting a response to invading microorganisms D) transporting nutrients to body cells

D

13) Blood flow through capillaries is controlled by A) one‐way valves. B) precapillary sphincters and smooth muscle in the walls of arterioles. C) smooth muscle in the walls of arterioles only. D) precapillary sphincters only.

D

5) Cardiac output is defined as the volume of blood pumped by a(n) ________ each time it contracts. A) atrioventricular valve B) heart C) atrium D) ventricle

D

6) Using a stethoscope, you listen to a beating heart and hear ʺlub‐dup, lub‐dup.ʺ These sounds are created by A) blood pressure differentials from chamber to chamber. B) muscles in the left ventricle. C) blood flowing through the aorta. D) blood recoiling against the closed valves

D

9) Which blood vessels have the thinnest walls? A) arterioles B) venules C) veins D) capillaries

D