Physiology II w/ Lab | Portage Learning | Q & A | 2026/2027
Edition (PDF)
**1. Which chamber of the heart pumps oxygenated blood into the systemic circulation?**
A) Right atrium
B) Right ventricle
C) Left atrium
D) Left ventricle
E) Coronary sinus
Correct Answer: Left ventricle
Rationale: The left ventricle pumps oxygenated blood into the aorta and systemic circulation. The right
ventricle pumps deoxygenated blood to the lungs, the atria are receiving chambers, and the coronary
sinus returns deoxygenated blood from the heart muscle itself.
**2. Blood returning from the systemic circulation first enters which chamber?**
A) Left atrium
B) Right atrium
C) Left ventricle
D) Right ventricle
E) Pulmonary trunk
Correct Answer: Right atrium
Rationale: Deoxygenated blood from the body returns via the superior and inferior venae cavae and
enters the right atrium. It then passes through the tricuspid valve into the right ventricle to be pumped
to the lungs.
**3. Which valve prevents backflow of blood from the right ventricle into the right atrium?**
,A) Mitral valve
B) Aortic valve
C) Pulmonary valve
D) Tricuspid valve
E) Bicuspid valve
Correct Answer: Tricuspid valve
Rationale: The tricuspid (right atrioventricular) valve prevents regurgitation of blood from the right
ventricle back into the right atrium. The mitral (bicuspid) valve is on the left side of the heart.
**4. The left atrioventricular valve is also known as the:**
A) Tricuspid valve
B) Pulmonary valve
C) Aortic valve
D) Mitral (bicuspid) valve
E) Semilunar valve
Correct Answer: Mitral (bicuspid) valve
Rationale: The left atrioventricular valve is the mitral (bicuspid) valve, which has two cusps. It prevents
backflow from the left ventricle into the left atrium during ventricular contraction.
**5. Which of the following correctly describes the flow of blood through the heart and lungs?**
A) Right atrium → right ventricle → pulmonary artery → lungs → pulmonary vein → left atrium → left
ventricle → aorta
B) Right atrium → left ventricle → pulmonary artery → lungs → pulmonary vein → left atrium → right
ventricle → aorta
C) Left atrium → left ventricle → pulmonary artery → lungs → pulmonary vein → right atrium → right
ventricle → aorta
, D) Right atrium → right ventricle → pulmonary vein → lungs → pulmonary artery → left atrium → left
ventricle → aorta
Correct Answer: Right atrium → right ventricle → pulmonary artery → lungs → pulmonary vein → left
atrium → left ventricle → aorta
Rationale: Deoxygenated blood flows from the right atrium to the right ventricle, then through the
pulmonary artery to the lungs. Oxygenated blood returns via the pulmonary veins to the left atrium,
passes to the left ventricle, and is pumped out through the aorta.
**6. Which layer of the heart wall is the thickest and responsible for the pumping action?**
A) Epicardium
B) Endocardium
C) Myocardium
D) Pericardium
E) Fibrous skeleton
Correct Answer: Myocardium
Rationale: The myocardium is the thickest layer of the heart wall, composed of cardiac muscle tissue
responsible for the heart's pumping action. The epicardium is the outer layer, the endocardium lines the
chambers, and the pericardium is the sac surrounding the heart.
**7. The outermost layer of the heart wall is the:**
A) Endocardium
B) Myocardium
C) Epicardium
D) Visceral pericardium
E) Both C and D
Correct Answer: Both C and D