18. The Heart

Which chamber generates the highest pressure during systole?

a. Right atrium

b. Right ventricle

c. Left atrium

d. Left ventricle

The first heart sound is called ________ and it is caused by the closing of the ________ valves. It occurs at the beginning of the ________ phase of the cardiac cycle. The second heart sound is called ________ and it is caused by the closing of the ________ valves. It occurs at the beginning of the ________ phase of the cardiac cycle.

Cardiac output is equal to:

a. End-diastolic volume minus end-systolic volume.

b. Heart rate multiplied by stroke volume.

c. Stroke volume divided by end-diastolic volume.

d. Heart rate multiplied by preload.

An increase in preload causes a/an ________ in stroke volume in accordance with the ________ law. An increase in afterload causes a/an ________ in stroke volume. An increase in contractility causes a/an ________ in stroke volume.

Which of the following statements is false?

a. The sympathetic nervous system releases epinephrine and norepinephrine, which are positive chronotropic and inotropic agents.

b. The endocrine system regulates cardiac output through chronotropic and inotropic hormones and through hormones that regulate water balance.

c. The parasympathetic nervous system releases acetylcholine and epinephrine, which are strongly negative inotropic agents.

d. Factors such as electrolyte concentrations, body temperature, and age all affect cardiac output.

You are an athletic trainer who is working with someone planning to run a marathon. Your trainee tells you to give him a workout that will make his heart 'beat faster than ever before.' What do you tell him about the effects of too rapid a heart rate?

More than one choice may apply.

Given a volume of 150 ml at the end of diastole, a volume of 50 ml at the end of systole, and a heart rate of 60 bpm, the cardiac output is

a. 600 ml/min

b. 6 liters/min

c. 1200 ml/min

d. 3 liters/min

Describe how heart contraction and relaxation influence coronary blood flow

Name the major branches of the coronary arteries, and note the heart regions served by each

Freshly oxygenated blood is first received by the:

a. Right atrium

b. Left atrium

c. Right ventricle

d. Left ventricle

The sequence of contraction of the heart chambers is:

a. Random

b. Left chambers followed by right chambers

c. Both atria followed by both ventricles

d. Right atrium, right ventricle, left atrium, left ventricle

When the semilunar valves are open, which of the following are occurring?

(1) Coronary arteries fill

(2) AV valves are closed

(3) Ventricles are in systole

(4) Ventricles are in diastole

(5) Blood enters the aorta

(6) Blood enters pulmonary arteries

(7) Atria contract

a. 2, 3, 5, 6

b. 1, 2, 3, 7

c. 1, 3, 5, 6

d. 2, 4, 5, 7

Mrs. Hamad, a middle-aged woman, is admitted to the coronary care unit with a diagnosis of left ventricular failure resulting from a myocardial infarction. Her chart indicates that she was awakened in the middle of the night by severe chest pain. Her skin is pale and cold, and moist sounds of pulmonary edema are heard over the lower regions of both lungs. Explain how failure of the left ventricle might cause these signs and symptoms.

What are the valves in the heart, and what is the function of each?

More than one choice may apply.

Soon after the onset of ventricular systole, the

a. AV valves close.

b. semilunar valves open.

c. first heart sound is heard.

d. aortic pressure increases.