Physiology I- Final Exam practice Questions

Question 1

1. Which of the following statements regarding carbon dioxide (CO2) transportation in the blood is correct?
   a. Carbon dioxide is transported mainly by hemoglobin.
   b. Carbon dioxide is transported mainly as bicarbonate (HCO3-) or carbamino compounds.
   c. Carbon dioxide is transported primarily in a dissolved form.
   d. Carbon dioxide is transported in red blood cells.

Answer 1

B.) Carbon dioxide is transported mainly as bicarbonate (HCO3-) or carbamino compounds.

Question 2

A specialized conduction system propagates the electrical activities in the heart. Which of the following
statements best describes this specialized conduction system?
a. Each normal heartbeat is initiated by an action potential that arises spontaneously in one of the pacemaker
cells in the atrioventricular node pacemaker cells.
b. The atrioventricular node and the first part of the atrioventricular bundle (Bundle of His) are the only routes
for propagating action potentials from the atria to the ventricles.
c. The AV Bundle beyond the first part, the left and right bundle branches, and the Purkinje fibers have the
unique property of prolonged conduction of action potentials (50 to 150 milliseconds).
d. Atrial contraction is followed immediately by ventricular contraction.

Answer 2

B.) The atrioventricular node and the first part of the atrioventricular bundle (Bundle of His) are the only routes

Question 3

3. Electrocardiogram (ECG) waves reveal electrical events in the heart. A typical lead I ECG has P, QRS, and
   T waves. The Q wave corresponds to the following electrical event in the heart:
   a. Atrial depolarization.
   b. Interventricular septum depolarizion.
   c. Atrial repolarization.
   d. Ventricular repolarization.

Answer 3

B.) Interventricular septum depolarizion.

Question 4

Mean aortic pressure is critical for blood supply and determined by cardiac output and total peripheral
resistance (TPR). Which of the following statements correctly describes the regulation of mean aortic
pressure?
a. The total peripheral resistance (TPR) is below the normal in a patient with hypertension
b. The total peripheral resistance (TPR) is above the normal during exercise
c. The mean aortic pressure is negligibly changed during exercise
d. The cardiac output is above normal in a patient with hypertension

Answer 4

C.) The mean aortic pressure is negligibly changed during exercise

Question 5

Blood volumes in the atria, ventricles, and arteries change during a cardiac cycle. Which of the following
statements correctly describes the blood volume change?
a. Stroke volume is the total volume of blood pumped by one ventricle in 1 minute
b. End-diastolic volume is the blood volume in each ventricle at the end of the systole
c. Cardiac output is the volume of blood ejected from one ventricle in one beat
d. End-systolic volume is the blood volume in each ventricle at the end of the systole

Answer 5

D.) End-systolic volume is the blood volume in each ventricle at the end of the systole

Question 6

6. Which of the following statements correctly describes one mechanism by which arteriolar vasodilation
   speeds the delivery of oxygen and metabolic substrates to the exercising muscle cells?
   a. Decrease in the diffusion area
   b. Increase in the distance between each exercising skeletal muscle cell and the nearest open capillaries
   c. Increase in the driving force for the diffusion of oxygen and metabolic substrates
   d. Decrease in diffusion coefficiency

Answer 6

C.) Increase in the driving force for the diffusion of oxygen and metabolic substrates

Question 7

Metabolic control is a local mechanism that matches tissue blood flow to its metabolic rate. Such a local
mechanism is essential for controlling blood flow in critical organs such as the brain, the heart (i.e., coronary
circulation), and working skeletal muscles. Which of the following biological processes is increased when the
metabolic rate in tissue is increased?
a. Precapillary sphincter tone
b. Number of open capillaries
c. Diffusion distance
d. Arteriolar resistance

Answer 7

B.) Number of open capillaries

Question 8

There are three types of beta-adrenergic receptors, i.e., beta1-adrenergic receptor, beta2-adrenergic
receptor, and beta3-adrenergic receptor. Activation of the beta1-adrenergic receptor causes:
a. the dilation of arterioles in the coronary circulation and skeletal muscles.
b. an increase in pacemaker rate, cell-to-cell propagation of action potentials, and cardiac muscle contractility.
c. arteriolar vasoconstriction in the systemic circulation.
d. venoconstriction in the systemic circulation that displaces venous blood toward the central circulation.

Answer 8

B.) an increase in pacemaker rate, cell-to-cell propagation of action potentials, and cardiac muscle contractility.

Question 9

Heart failure is a condition where depressed cardiac contractility limits the heart’s ability to deliver an
adequate cardiac output. Immediately following a left ventricle failure, the arterial baroreflex works to
compensate for the failing heart. One of the consequences of the baroreflex is
a. an increase in parasympathetic activity.
b. a reduction in left ventricle preload.
c. an increase in total peripheral resistance (TPR).
d. the vasodilation in noncritical organs, such as kidneys, splanchnic organs, resting muscles, and mucosa.

Answer 9

C.) an increase in total peripheral resistance (TPR).