,TEST BANK
, Question 1
Which statement best describes the anatomical location of the heart?
A. It lies entirely in the right side of the thoracic cavity, below the right
lung. B. It lies in the mediastinum between the lungs, posterior to the
sternum and superior to the diaphragm. C. It lies in the abdominal
cavity, immediately inferior to the diaphragm. D. It lies posterior to the
vertebral column and superior to the esophagus.
Correct Answer: B. It lies in the mediastinum between the lungs,
posterior to the sternum and superior to the diaphragm.
Rationale: The heart is located in the mediastinum, between the lungs,
behind the sternum, and above the diaphragm. Its apex generally points
downward, forward, and to the left. Option A is incorrect because the
heart is not confined to the right thoracic cavity. Option C places the
heart in the wrong body cavity. Option D is incorrect because the heart
lies anterior to the vertebral column.
Question 2
Which layer of the heart wall is primarily responsible for generating the
force that ejects blood into the pulmonary artery and aorta?
A. Endocardium B. Myocardium C. Visceral pericardium D. Parietal
pericardium
Correct Answer: B. Myocardium
Rationale: The myocardium is the muscular middle layer of the heart
wall. Its cardiac muscle cells contract to produce the pressure needed to
pump blood into the pulmonary and systemic circulations. The
endocardium lines the chambers and covers the valves. The visceral