BIOL 252 Human Anatomy & Physiology II (Lab):
Module 2 Exam Review – Cardiovascular
System, 85 Q&A (Portage Learning, LockDown
----------------------------------------------------------------------------------------------------
SECTION I: ANATOMY OF THE HEART, PERICARDIUM, AND GREAT VESSELS
1. Diagram Identification: Locate the pulmonary valve in the provided anterior heart
diagram and describe its physiological role.
Answer: The pulmonary valve is located at the base of the pulmonary trunk arising from
the right ventricle. It functions as a semilunar valve that opens during right ventricular
systole to allow deoxygenated blood to enter the pulmonary circuit and snaps shut
during diastole to prevent regurgitation.
2. Diagram Identification: Identify the vessel that carries oxygenated blood from the
lungs back to the left atrium.
Answer: The pulmonary veins, typically appearing as four separate vessels entering the
posterior aspect of the left atrium.
3. Describe the structural layers of the pericardium and their histological composition.
Answer: The pericardium consists of an outer fibrous pericardium made of dense
irregular connective tissue, and an inner serous pericardium. The serous pericardium is
subdivided into the parietal layer lining the fibrous sac and the visceral layer
(epicardium) covering the heart surface.
4. Explain the purpose and clinical significance of the pericardial cavity and pericardial
fluid.
,Answer: The pericardial cavity contains fifteen to fifty milliliters of serous fluid that
reduces friction as the heart beats. Accumulation of excess fluid leads to cardiac
tamponade, which compresses the chambers and reduces stroke volume.
5. List the three layers of the heart wall from superficial to deep and describe their
primary tissues.
Answer: Epicardium (simple squamous epithelium and adipose tissue), Myocardium
(cardiac muscle tissue responsible for contraction), and Endocardium (endothelium and
subendothelial connective tissue lining the chambers).
6. Contrast the anatomical differences between the left ventricle and the right ventricle
and explain the functional reason for this difference.
Answer: The left ventricle has a myocardium that is three times thicker than the right
ventricle. This is because the left ventricle must generate high pressure (one hundred
twenty millimeters of mercury) to pump blood through the high-resistance systemic
circuit, whereas the right ventricle pumps into the low-resistance pulmonary circuit
(twenty five millimeters of mercury).
7. Describe the role of the chordae tendineae and papillary muscles in valve function.
Answer: They do not open the atrioventricular (AV) valves; rather, they prevent the valve
cusps from everting or prolapsing into the atria when the ventricles contract under high
pressure.
8. Outline the pathway of a drop of blood through the heart, beginning at the superior
vena cava and ending at the ascending aorta.
Answer: Superior vena cava to right atrium, through tricuspid valve to right ventricle,
through pulmonary semilunar valve to pulmonary trunk and lungs, through pulmonary
veins to left atrium, through bicuspid (mitral) valve to left ventricle, through aortic
semilunar valve to ascending aorta.
9. Define the fibrous skeleton of the heart and list its three primary functions.
, Answer: A framework of dense connective tissue rings around the valves. It provides
structural support for the valves, serves as the point of insertion for cardiac muscle
bundles, and acts as an electrical insulator between atria and ventricles.
10. Describe the origin and distribution of the left coronary artery.
Answer: Arises from the ascending aorta and branches into the anterior interventricular
artery (left anterior descending) and the circumflex artery, supplying the left atrium and
left ventricle.
11. Describe the origin and distribution of the right coronary artery.
Answer: Arises from the ascending aorta and branches into the marginal artery and the
posterior interventricular artery, supplying the right atrium, right ventricle, and the
posterior interventricular septum.
12. Explain the significance of collateral circulation and anastomoses in the coronary
circulation.
Answer: Anastomoses are connections between arterial branches that provide
alternative pathways for blood flow. If one artery is slowly blocked by plaque, collateral
vessels can enlarge to provide blood flow to the threatened myocardium.
13. How is deoxygenated blood drained from the myocardium and returned to the
systemic circulation?
Answer: Cardiac veins (great, middle, and small) collect blood from the capillary beds
and drain into the coronary sinus, which empties directly into the right atrium.
14. Define myocardial ischemia and differentiate it from myocardial infarction.
Answer: Myocardial ischemia is a reversible condition of inadequate blood flow and
oxygen to the heart muscle, often causing angina pectoris. Myocardial infarction is
irreversible necrosis of myocardial tissue resulting from prolonged, complete obstruction
of blood flow.
15. What is the ligamentum arteriosum and what was its fetal precursor?
Module 2 Exam Review – Cardiovascular
System, 85 Q&A (Portage Learning, LockDown
----------------------------------------------------------------------------------------------------
SECTION I: ANATOMY OF THE HEART, PERICARDIUM, AND GREAT VESSELS
1. Diagram Identification: Locate the pulmonary valve in the provided anterior heart
diagram and describe its physiological role.
Answer: The pulmonary valve is located at the base of the pulmonary trunk arising from
the right ventricle. It functions as a semilunar valve that opens during right ventricular
systole to allow deoxygenated blood to enter the pulmonary circuit and snaps shut
during diastole to prevent regurgitation.
2. Diagram Identification: Identify the vessel that carries oxygenated blood from the
lungs back to the left atrium.
Answer: The pulmonary veins, typically appearing as four separate vessels entering the
posterior aspect of the left atrium.
3. Describe the structural layers of the pericardium and their histological composition.
Answer: The pericardium consists of an outer fibrous pericardium made of dense
irregular connective tissue, and an inner serous pericardium. The serous pericardium is
subdivided into the parietal layer lining the fibrous sac and the visceral layer
(epicardium) covering the heart surface.
4. Explain the purpose and clinical significance of the pericardial cavity and pericardial
fluid.
,Answer: The pericardial cavity contains fifteen to fifty milliliters of serous fluid that
reduces friction as the heart beats. Accumulation of excess fluid leads to cardiac
tamponade, which compresses the chambers and reduces stroke volume.
5. List the three layers of the heart wall from superficial to deep and describe their
primary tissues.
Answer: Epicardium (simple squamous epithelium and adipose tissue), Myocardium
(cardiac muscle tissue responsible for contraction), and Endocardium (endothelium and
subendothelial connective tissue lining the chambers).
6. Contrast the anatomical differences between the left ventricle and the right ventricle
and explain the functional reason for this difference.
Answer: The left ventricle has a myocardium that is three times thicker than the right
ventricle. This is because the left ventricle must generate high pressure (one hundred
twenty millimeters of mercury) to pump blood through the high-resistance systemic
circuit, whereas the right ventricle pumps into the low-resistance pulmonary circuit
(twenty five millimeters of mercury).
7. Describe the role of the chordae tendineae and papillary muscles in valve function.
Answer: They do not open the atrioventricular (AV) valves; rather, they prevent the valve
cusps from everting or prolapsing into the atria when the ventricles contract under high
pressure.
8. Outline the pathway of a drop of blood through the heart, beginning at the superior
vena cava and ending at the ascending aorta.
Answer: Superior vena cava to right atrium, through tricuspid valve to right ventricle,
through pulmonary semilunar valve to pulmonary trunk and lungs, through pulmonary
veins to left atrium, through bicuspid (mitral) valve to left ventricle, through aortic
semilunar valve to ascending aorta.
9. Define the fibrous skeleton of the heart and list its three primary functions.
, Answer: A framework of dense connective tissue rings around the valves. It provides
structural support for the valves, serves as the point of insertion for cardiac muscle
bundles, and acts as an electrical insulator between atria and ventricles.
10. Describe the origin and distribution of the left coronary artery.
Answer: Arises from the ascending aorta and branches into the anterior interventricular
artery (left anterior descending) and the circumflex artery, supplying the left atrium and
left ventricle.
11. Describe the origin and distribution of the right coronary artery.
Answer: Arises from the ascending aorta and branches into the marginal artery and the
posterior interventricular artery, supplying the right atrium, right ventricle, and the
posterior interventricular septum.
12. Explain the significance of collateral circulation and anastomoses in the coronary
circulation.
Answer: Anastomoses are connections between arterial branches that provide
alternative pathways for blood flow. If one artery is slowly blocked by plaque, collateral
vessels can enlarge to provide blood flow to the threatened myocardium.
13. How is deoxygenated blood drained from the myocardium and returned to the
systemic circulation?
Answer: Cardiac veins (great, middle, and small) collect blood from the capillary beds
and drain into the coronary sinus, which empties directly into the right atrium.
14. Define myocardial ischemia and differentiate it from myocardial infarction.
Answer: Myocardial ischemia is a reversible condition of inadequate blood flow and
oxygen to the heart muscle, often causing angina pectoris. Myocardial infarction is
irreversible necrosis of myocardial tissue resulting from prolonged, complete obstruction
of blood flow.
15. What is the ligamentum arteriosum and what was its fetal precursor?
