BIOS 255 EDAPT Week 4 - Anatomy & Physiology III Heart and
Cardiovascular System Study Guide 2026 Chamberlain College
1. Which layer of the heart wall is composed primarily of cardiac muscle tissue?
A. Epicardium
B. Pericardium
C. Endocardium
D. Myocardium
Answer: D
Rationale: The myocardium is the middle layer of the heart wall and is composed of
cardiac muscle cells responsible for the heart’s pumping action.
2. The double-walled sac that encloses the heart is called the:
A. Pleura
B. Peritoneum
C. Pericardium
D. Endothelium
Answer: C
Rationale: The pericardium is the fibrous and serous sac that protects the heart and
anchors it to surrounding structures.
,3. Which heart chamber receives deoxygenated blood returning from the
systemic circuit?
A. Left Atrium
B. Right Atrium
C. Left Ventricle
D. Right Ventricle
Answer: B
Rationale: The right atrium receives deoxygenated blood from the superior and inferior
vena cavae and the coronary sinus.
4. The valve located between the right atrium and the right ventricle is the:
A. Pulmonary Valve
B. Bicuspid Valve
C. Aortic Valve
D. Tricuspid Valve
Answer: D
Rationale: The tricuspid valve (right atrioventricular valve) prevents backflow of blood
into the right atrium when the right ventricle contracts.
5. Which structure prevents the AV valves from everting into the atria during
ventricular contraction?
A. Pectinate muscles
B. Chordae tendineae
C. Interventricular septum
D. Fossa ovalis
Answer: B
Rationale: Chordae tendineae, or ‘heart strings,’ are anchored by papillary muscles and
keep the AV valve cusps from flipping backward.
, 6. Which vessel carries oxygenated blood from the lungs back to the heart?
A. Pulmonary Vein
B. Aorta
C. Pulmonary Artery
D. Superior Vena Cava
Answer: A
Rationale: Pulmonary veins are unique because they carry oxygen-rich blood from the
lungs to the left atrium.
7. The heart’s natural pacemaker is the:
A. Atrioventricular (AV) node
B. Purkinje fibers
C. Bundle of His
D. Sinoatrial (SA) node
Answer: D
Rationale: The SA node, located in the right atrium, initiates each heartbeat and sets the
sinus rhythm.
8. On an ECG, the P wave represents:
A. Ventricular depolarization
B. Atrial depolarization
C. Atrial repolarization
D. Ventricular repolarization
Answer: B
Rationale: The P wave is the first wave on the ECG and signifies the electrical signal
causing the atria to contract.
Cardiovascular System Study Guide 2026 Chamberlain College
1. Which layer of the heart wall is composed primarily of cardiac muscle tissue?
A. Epicardium
B. Pericardium
C. Endocardium
D. Myocardium
Answer: D
Rationale: The myocardium is the middle layer of the heart wall and is composed of
cardiac muscle cells responsible for the heart’s pumping action.
2. The double-walled sac that encloses the heart is called the:
A. Pleura
B. Peritoneum
C. Pericardium
D. Endothelium
Answer: C
Rationale: The pericardium is the fibrous and serous sac that protects the heart and
anchors it to surrounding structures.
,3. Which heart chamber receives deoxygenated blood returning from the
systemic circuit?
A. Left Atrium
B. Right Atrium
C. Left Ventricle
D. Right Ventricle
Answer: B
Rationale: The right atrium receives deoxygenated blood from the superior and inferior
vena cavae and the coronary sinus.
4. The valve located between the right atrium and the right ventricle is the:
A. Pulmonary Valve
B. Bicuspid Valve
C. Aortic Valve
D. Tricuspid Valve
Answer: D
Rationale: The tricuspid valve (right atrioventricular valve) prevents backflow of blood
into the right atrium when the right ventricle contracts.
5. Which structure prevents the AV valves from everting into the atria during
ventricular contraction?
A. Pectinate muscles
B. Chordae tendineae
C. Interventricular septum
D. Fossa ovalis
Answer: B
Rationale: Chordae tendineae, or ‘heart strings,’ are anchored by papillary muscles and
keep the AV valve cusps from flipping backward.
, 6. Which vessel carries oxygenated blood from the lungs back to the heart?
A. Pulmonary Vein
B. Aorta
C. Pulmonary Artery
D. Superior Vena Cava
Answer: A
Rationale: Pulmonary veins are unique because they carry oxygen-rich blood from the
lungs to the left atrium.
7. The heart’s natural pacemaker is the:
A. Atrioventricular (AV) node
B. Purkinje fibers
C. Bundle of His
D. Sinoatrial (SA) node
Answer: D
Rationale: The SA node, located in the right atrium, initiates each heartbeat and sets the
sinus rhythm.
8. On an ECG, the P wave represents:
A. Ventricular depolarization
B. Atrial depolarization
C. Atrial repolarization
D. Ventricular repolarization
Answer: B
Rationale: The P wave is the first wave on the ECG and signifies the electrical signal
causing the atria to contract.
