BIOS 255 EXAM 2 2026/2027 | Anatomy and Physiology III
Review | Verified Q&A | Chamberlain | Pass Guaranteed - A+
Graded
SECTION 1: CARDIOVASCULAR SYSTEM - ANATOMY & HEART STRUCTURE
Q1: A patient undergoes emergency pericardiocentesis for cardiac tamponade. The
needle is inserted into the pericardial cavity to drain excess fluid. Which layer of the
pericardium is directly adherent to the surface of the heart?
A. The fibrous pericardium, which is the tough outer layer attached to the great vessels.
B. The parietal layer of the serous pericardium, which lines the inner surface of the
fibrous pericardium.
C. The visceral layer of the serous pericardium (epicardium), which is inseparable from
the heart wall itself. [CORRECT]
D. The mediastinal pleura, which reflects over the heart as a protective sheath.
Correct Answer: C
Rationale: The visceral layer of the serous pericardium, also known as the epicardium, is
the innermost layer that directly covers the heart and great vessels; it is continuous with
the parietal layer at the roots of the great vessels, and the pericardial cavity lies between
these two serous layers. Option A is incorrect because the fibrous pericardium is the
tough outer layer and does not adhere directly to the heart surface. Option B is incorrect
because the parietal layer lines the fibrous pericardium, not the heart itself. Option D is
incorrect because the mediastinal pleura is part of the pleural sac surrounding the
lungs, not the pericardium. RATED A ✓
Q2: During open-heart surgery, a surgeon observes the thickest muscular layer of the
heart wall. This layer is responsible for the pumping action and is known as:
A. The epicardium, which contains coronary blood vessels and adipose tissue.
B. The endocardium, which provides a smooth lining for blood flow and houses the
cardiac conduction system.
C. The myocardium, composed of cardiac muscle tissue with intercalated discs for
synchronized contraction. [CORRECT]
,D. The fibrous skeleton, which provides structural support for valve attachment.
Correct Answer: C
Rationale: The myocardium is the thick middle layer of the heart wall composed of
cardiac muscle tissue arranged in spiral bundles; intercalated discs contain gap
junctions and desmosomes that allow rapid electrical conduction and mechanical
coupling, enabling the synchronized pumping action of the heart. Option A is incorrect
because the epicardium is the thin outer layer. Option B is incorrect because the
endocardium is the thin inner endothelial lining. Option D is incorrect because the
fibrous skeleton is a connective tissue framework, not the muscular pumping layer.
RATED A ✓
Q3: A cardiac catheter is advanced from the right femoral vein into the right side of the
heart. As the catheter passes through the right atrium, it encounters a thin muscular
ridge that separates the smooth-walled posterior sinus venarum from the rough-walled
anterior portion. This structure is the:
A. Fossa ovalis, which is the embryonic remnant of the foramen ovale.
B. Crista terminalis, which marks the boundary between the sinus venarum and the
rough atrium proper. [CORRECT]
C. Interatrial septum, which separates the right and left atria.
D. Trabeculae carneae, which are muscular ridges found in the ventricles.
Correct Answer: B
Rationale: The crista terminalis is a vertical muscular ridge on the inner wall of the right
atrium that separates the smooth posterior region (sinus venarum, derived from the
embryonic sinus venosus) from the rough anterior region (atrium proper, containing
pectinate muscles); it also serves as the site of the sinoatrial node. Option A is incorrect
because the fossa ovalis is a depression in the interatrial septum, not a ridge separating
atrial regions. Option C is incorrect because the interatrial septum separates the two
atria, not regions within the right atrium. Option D is incorrect because trabeculae
carneae are found in the ventricles, not the atrium. RATED A ✓
Q4: A patient with chronic rheumatic heart disease develops mitral stenosis. The nurse
practitioner understands that the mitral (bicuspid) valve is best characterized by which
anatomical feature?
,A. It is located between the right atrium and right ventricle and has three cusps.
B. It is located between the left atrium and left ventricle and is anchored by chordae
tendineae attached to papillary muscles. [CORRECT]
C. It is a semilunar valve guarding the entrance to the pulmonary trunk.
D. It is composed of three pocket-like cusps that prevent backflow into the left ventricle.
Correct Answer: B
Rationale: The mitral (bicuspid) valve is the left atrioventricular valve located between
the left atrium and left ventricle; it has two cusps (anterior and posterior) and is
anchored by chordae tendineae connected to anterolateral and posteromedial papillary
muscles, which prevent valve prolapse during ventricular systole. Option A is incorrect
because this describes the tricuspid valve. Option C is incorrect because this describes
the pulmonary valve. Option D is incorrect because three pocket-like cusps describe the
semilunar valves (aortic and pulmonary), not the mitral valve. RATED A ✓
Q5: During a cardiac examination, a nurse practitioner auscultates the pulmonary valve
at the second intercostal space just left of the sternum. Anatomically, this valve is
situated at the junction between:
A. The right ventricle and the ascending aorta.
B. The left ventricle and the aorta.
C. The right ventricle and the pulmonary trunk. [CORRECT]
D. The right atrium and the superior vena cava.
Correct Answer: C
Rationale: The pulmonary (pulmonic) semilunar valve is located at the junction between
the right ventricle and the pulmonary trunk; it prevents backflow of blood from the
pulmonary trunk into the right ventricle during diastole and is best auscultated at the left
second intercostal space adjacent to the sternum. Option A is incorrect because the
right ventricle connects to the pulmonary trunk, not the ascending aorta. Option B is
incorrect because this describes the aortic valve. Option D is incorrect because there is
no valve between the right atrium and superior vena cava. RATED A ✓
Q6: A patient with infective endocarditis develops vegetation on the aortic valve. The
nurse practitioner understands that the right and left coronary arteries arise
immediately superior to this valve from the:
A. Ascending aorta, just above the aortic sinuses (sinuses of Valsalva). [CORRECT]
, B. Pulmonary trunk, which carries deoxygenated blood to the lungs.
C. Aortic arch, distal to the brachiocephalic trunk.
D. Descending aorta, posterior to the heart.
Correct Answer: A
Rationale: The right and left coronary arteries originate from the right and left aortic
sinuses (sinuses of Valsalva) located immediately superior to the aortic valve cusps
within the ascending aorta; these arteries are the first branches of the aorta and supply
oxygenated blood to the myocardium. Option B is incorrect because the pulmonary
trunk carries deoxygenated blood and does not give rise to coronary arteries. Option C
is incorrect because the coronary arteries arise proximal to the aortic arch. Option D is
incorrect because the descending aorta is distal and does not give rise to coronary
arteries. RATED A ✓
Q7: During a coronary angiogram, the cardiologist injects contrast into the left coronary
artery. The nurse practitioner observes that this artery typically bifurcates into which
two major branches that supply the left ventricle and interventricular septum?
A. The right marginal artery and the posterior interventricular artery.
B. The left anterior descending artery and the circumflex artery. [CORRECT]
C. The sinoatrial nodal artery and the atrioventricular nodal artery.
D. The anterior interventricular artery and the right coronary artery.
Correct Answer: B
Rationale: The left coronary artery (left main coronary artery) typically bifurcates into
the left anterior descending (LAD) artery, which supplies the anterior wall of the left
ventricle and anterior interventricular septum, and the circumflex artery, which supplies
the left atrium and lateral/posterior walls of the left ventricle; this distribution is
clinically critical in myocardial infarction localization. Option A is incorrect because
these are branches of the right coronary artery. Option C is incorrect because these are
smaller branches that may arise from either coronary artery. Option D is incorrect
because the right coronary artery is a separate vessel arising from the aorta, not a
branch of the left coronary artery. RATED A ✓
Review | Verified Q&A | Chamberlain | Pass Guaranteed - A+
Graded
SECTION 1: CARDIOVASCULAR SYSTEM - ANATOMY & HEART STRUCTURE
Q1: A patient undergoes emergency pericardiocentesis for cardiac tamponade. The
needle is inserted into the pericardial cavity to drain excess fluid. Which layer of the
pericardium is directly adherent to the surface of the heart?
A. The fibrous pericardium, which is the tough outer layer attached to the great vessels.
B. The parietal layer of the serous pericardium, which lines the inner surface of the
fibrous pericardium.
C. The visceral layer of the serous pericardium (epicardium), which is inseparable from
the heart wall itself. [CORRECT]
D. The mediastinal pleura, which reflects over the heart as a protective sheath.
Correct Answer: C
Rationale: The visceral layer of the serous pericardium, also known as the epicardium, is
the innermost layer that directly covers the heart and great vessels; it is continuous with
the parietal layer at the roots of the great vessels, and the pericardial cavity lies between
these two serous layers. Option A is incorrect because the fibrous pericardium is the
tough outer layer and does not adhere directly to the heart surface. Option B is incorrect
because the parietal layer lines the fibrous pericardium, not the heart itself. Option D is
incorrect because the mediastinal pleura is part of the pleural sac surrounding the
lungs, not the pericardium. RATED A ✓
Q2: During open-heart surgery, a surgeon observes the thickest muscular layer of the
heart wall. This layer is responsible for the pumping action and is known as:
A. The epicardium, which contains coronary blood vessels and adipose tissue.
B. The endocardium, which provides a smooth lining for blood flow and houses the
cardiac conduction system.
C. The myocardium, composed of cardiac muscle tissue with intercalated discs for
synchronized contraction. [CORRECT]
,D. The fibrous skeleton, which provides structural support for valve attachment.
Correct Answer: C
Rationale: The myocardium is the thick middle layer of the heart wall composed of
cardiac muscle tissue arranged in spiral bundles; intercalated discs contain gap
junctions and desmosomes that allow rapid electrical conduction and mechanical
coupling, enabling the synchronized pumping action of the heart. Option A is incorrect
because the epicardium is the thin outer layer. Option B is incorrect because the
endocardium is the thin inner endothelial lining. Option D is incorrect because the
fibrous skeleton is a connective tissue framework, not the muscular pumping layer.
RATED A ✓
Q3: A cardiac catheter is advanced from the right femoral vein into the right side of the
heart. As the catheter passes through the right atrium, it encounters a thin muscular
ridge that separates the smooth-walled posterior sinus venarum from the rough-walled
anterior portion. This structure is the:
A. Fossa ovalis, which is the embryonic remnant of the foramen ovale.
B. Crista terminalis, which marks the boundary between the sinus venarum and the
rough atrium proper. [CORRECT]
C. Interatrial septum, which separates the right and left atria.
D. Trabeculae carneae, which are muscular ridges found in the ventricles.
Correct Answer: B
Rationale: The crista terminalis is a vertical muscular ridge on the inner wall of the right
atrium that separates the smooth posterior region (sinus venarum, derived from the
embryonic sinus venosus) from the rough anterior region (atrium proper, containing
pectinate muscles); it also serves as the site of the sinoatrial node. Option A is incorrect
because the fossa ovalis is a depression in the interatrial septum, not a ridge separating
atrial regions. Option C is incorrect because the interatrial septum separates the two
atria, not regions within the right atrium. Option D is incorrect because trabeculae
carneae are found in the ventricles, not the atrium. RATED A ✓
Q4: A patient with chronic rheumatic heart disease develops mitral stenosis. The nurse
practitioner understands that the mitral (bicuspid) valve is best characterized by which
anatomical feature?
,A. It is located between the right atrium and right ventricle and has three cusps.
B. It is located between the left atrium and left ventricle and is anchored by chordae
tendineae attached to papillary muscles. [CORRECT]
C. It is a semilunar valve guarding the entrance to the pulmonary trunk.
D. It is composed of three pocket-like cusps that prevent backflow into the left ventricle.
Correct Answer: B
Rationale: The mitral (bicuspid) valve is the left atrioventricular valve located between
the left atrium and left ventricle; it has two cusps (anterior and posterior) and is
anchored by chordae tendineae connected to anterolateral and posteromedial papillary
muscles, which prevent valve prolapse during ventricular systole. Option A is incorrect
because this describes the tricuspid valve. Option C is incorrect because this describes
the pulmonary valve. Option D is incorrect because three pocket-like cusps describe the
semilunar valves (aortic and pulmonary), not the mitral valve. RATED A ✓
Q5: During a cardiac examination, a nurse practitioner auscultates the pulmonary valve
at the second intercostal space just left of the sternum. Anatomically, this valve is
situated at the junction between:
A. The right ventricle and the ascending aorta.
B. The left ventricle and the aorta.
C. The right ventricle and the pulmonary trunk. [CORRECT]
D. The right atrium and the superior vena cava.
Correct Answer: C
Rationale: The pulmonary (pulmonic) semilunar valve is located at the junction between
the right ventricle and the pulmonary trunk; it prevents backflow of blood from the
pulmonary trunk into the right ventricle during diastole and is best auscultated at the left
second intercostal space adjacent to the sternum. Option A is incorrect because the
right ventricle connects to the pulmonary trunk, not the ascending aorta. Option B is
incorrect because this describes the aortic valve. Option D is incorrect because there is
no valve between the right atrium and superior vena cava. RATED A ✓
Q6: A patient with infective endocarditis develops vegetation on the aortic valve. The
nurse practitioner understands that the right and left coronary arteries arise
immediately superior to this valve from the:
A. Ascending aorta, just above the aortic sinuses (sinuses of Valsalva). [CORRECT]
, B. Pulmonary trunk, which carries deoxygenated blood to the lungs.
C. Aortic arch, distal to the brachiocephalic trunk.
D. Descending aorta, posterior to the heart.
Correct Answer: A
Rationale: The right and left coronary arteries originate from the right and left aortic
sinuses (sinuses of Valsalva) located immediately superior to the aortic valve cusps
within the ascending aorta; these arteries are the first branches of the aorta and supply
oxygenated blood to the myocardium. Option B is incorrect because the pulmonary
trunk carries deoxygenated blood and does not give rise to coronary arteries. Option C
is incorrect because the coronary arteries arise proximal to the aortic arch. Option D is
incorrect because the descending aorta is distal and does not give rise to coronary
arteries. RATED A ✓
Q7: During a coronary angiogram, the cardiologist injects contrast into the left coronary
artery. The nurse practitioner observes that this artery typically bifurcates into which
two major branches that supply the left ventricle and interventricular septum?
A. The right marginal artery and the posterior interventricular artery.
B. The left anterior descending artery and the circumflex artery. [CORRECT]
C. The sinoatrial nodal artery and the atrioventricular nodal artery.
D. The anterior interventricular artery and the right coronary artery.
Correct Answer: B
Rationale: The left coronary artery (left main coronary artery) typically bifurcates into
the left anterior descending (LAD) artery, which supplies the anterior wall of the left
ventricle and anterior interventricular septum, and the circumflex artery, which supplies
the left atrium and lateral/posterior walls of the left ventricle; this distribution is
clinically critical in myocardial infarction localization. Option A is incorrect because
these are branches of the right coronary artery. Option C is incorrect because these are
smaller branches that may arise from either coronary artery. Option D is incorrect
because the right coronary artery is a separate vessel arising from the aorta, not a
branch of the left coronary artery. RATED A ✓
