NU110 Exam 3 Actual Exam Style V3 | NU
110 Integrated Human Sciences | Galen
1. Which chamber of the heart receives deoxygenated blood from the superior and inferior
vena cavae?
A. Left Atrium
B. Right Ventricle
C. Left Ventricle
D. Right Atrium
Answer: D
Rationale: The right atrium serves as the receiving chamber for systemic deoxygenated
blood. It collects blood from the vena cavae and the coronary sinus before moving it to the
right ventricle. This marks the beginning of the heart’s pulmonary circulation cycle.
2. What is the primary function of the SA node in the cardiac conduction system?
A. To act as the secondary pacemaker
B. To initiate the electrical impulse for the heartbeat
C. To delay the electrical signal before it reaches the ventricles
D. To conduct impulses directly to the Purkinje fibers
Answer: B
,Rationale: The SA node is known as the natural pacemaker of the heart because it initiates
the action potential. This electrical signal spreads across the atria, causing them to contract.
It typically maintains a resting heart rate between sixty and one hundred beats per minute.
3. Which valve prevents the backflow of blood from the left ventricle into the left atrium?
A. Tricuspid valve
B. Mitral (Bicuspid) valve
C. Aortic semilunar valve
D. Pulmonary semilunar valve
Answer: B
Rationale: The mitral valve is located between the left atrium and the left ventricle. Its
main purpose is to ensure that blood flows in only one direction toward the aorta. When
the left ventricle contracts, this valve closes to prevent regurgitation into the atrium.
4. What does the P wave represent on an Electrocardiogram (ECG)?
A. Atrial depolarization
B. Atrial repolarization
C. Ventricular depolarization
D. Ventricular repolarization
Answer: A
, Rationale: The P wave is the first deflection seen on a standard ECG tracing. It represents
the electrical activation or depolarization of the atria. Shortly after this electrical event, the
atrial muscle contracts to pump blood into the ventricles.
5. Which component of the blood is responsible for transporting oxygen?
A. Platelets
B. Leukocytes
C. Plasma
D. Erythrocytes
Answer: D
Rationale: Erythrocytes, or red blood cells, contain the protein hemoglobin which binds to
oxygen molecules. This allows oxygen to be transported from the lungs to various tissues
throughout the body. Their biconcave shape increases the surface area available for gas
exchange.
6. What is the term for the percentage of total blood volume that consists of red blood cells?
A. Hemoglobin concentration
B. Plasma ratio
C. Hematocrit
D. Erythropoiesis
Answer: C
110 Integrated Human Sciences | Galen
1. Which chamber of the heart receives deoxygenated blood from the superior and inferior
vena cavae?
A. Left Atrium
B. Right Ventricle
C. Left Ventricle
D. Right Atrium
Answer: D
Rationale: The right atrium serves as the receiving chamber for systemic deoxygenated
blood. It collects blood from the vena cavae and the coronary sinus before moving it to the
right ventricle. This marks the beginning of the heart’s pulmonary circulation cycle.
2. What is the primary function of the SA node in the cardiac conduction system?
A. To act as the secondary pacemaker
B. To initiate the electrical impulse for the heartbeat
C. To delay the electrical signal before it reaches the ventricles
D. To conduct impulses directly to the Purkinje fibers
Answer: B
,Rationale: The SA node is known as the natural pacemaker of the heart because it initiates
the action potential. This electrical signal spreads across the atria, causing them to contract.
It typically maintains a resting heart rate between sixty and one hundred beats per minute.
3. Which valve prevents the backflow of blood from the left ventricle into the left atrium?
A. Tricuspid valve
B. Mitral (Bicuspid) valve
C. Aortic semilunar valve
D. Pulmonary semilunar valve
Answer: B
Rationale: The mitral valve is located between the left atrium and the left ventricle. Its
main purpose is to ensure that blood flows in only one direction toward the aorta. When
the left ventricle contracts, this valve closes to prevent regurgitation into the atrium.
4. What does the P wave represent on an Electrocardiogram (ECG)?
A. Atrial depolarization
B. Atrial repolarization
C. Ventricular depolarization
D. Ventricular repolarization
Answer: A
, Rationale: The P wave is the first deflection seen on a standard ECG tracing. It represents
the electrical activation or depolarization of the atria. Shortly after this electrical event, the
atrial muscle contracts to pump blood into the ventricles.
5. Which component of the blood is responsible for transporting oxygen?
A. Platelets
B. Leukocytes
C. Plasma
D. Erythrocytes
Answer: D
Rationale: Erythrocytes, or red blood cells, contain the protein hemoglobin which binds to
oxygen molecules. This allows oxygen to be transported from the lungs to various tissues
throughout the body. Their biconcave shape increases the surface area available for gas
exchange.
6. What is the term for the percentage of total blood volume that consists of red blood cells?
A. Hemoglobin concentration
B. Plasma ratio
C. Hematocrit
D. Erythropoiesis
Answer: C
