Midterms Quizzes

Question 1

Which of the following statements is CORRECT regarding the cardiac muscle fibers?
A. There are three types of cardiac muscle fibers -

B. Striation is characterized by bundles or fascicle-like appearance
C The fibers are arranged in a lattice work,
D. Gap junctions provide intercellular communication among fibers

Answer 1

C and D

Question 2

What provides the ONLY connection between the Atria and the Ventricles?

Answer 2

AV node

Question 3

Which extracellular fluid ion is the cardiac muscles. more dependent for its contraction?

Answer 3

Calcium ions.

Question 4

Which part of the conduction system is the cardiac impulse delayed?

Answer 4

Atrioventricular Node

Question 5

Which channel will open to cause the depolarization in the sinoatrial node?

Answer 5

Sodium Channels

Question 6

Which of the following statements is CORRECT regarding the Frank-Starling Mechanism?

A. The decreased volume of blood stretches the cardiac muscles causing an increase in the strength of contractility
B. The increased volume of blood stretches the cardiac muscles causing increase in the strength of contractility

Answer 6

B. The increased volume of blood stretches the cardiac muscles causing increase in the strength of contractility

Question 7

8. Which of the following is NOT a function of the skeleton of the heart?
   A. Separate the muscular walls of the atria from those of the ventricles
   B. Provide muscular attachment for leaflets & cusps of the valves & myocardium

Answer 7

B. Provide muscular attachment for leaflets & cusps of the valves & myocardium

Question 8

Which of the following factors contribute to the Syncytium characteristic of the cardiac muscle fiber?
A. The presence of intercalated disks that contain Adherents Junctions

B. The presence of intercalated disks that contain
Gap Junctions

Answer 8

B. . The presence of intercalated disks that contain
Gap Junctions

Question 9

This is the normal anatomical pacemaker of the heart:

Answer 9

SA node

Question 10

Before the cardiac impulse reaches the atrioventricular node, which of the following is the impulse conducted?
A. Bundle of His
C. Bundle Branches
B. Internodal Pathway
D. Purkinje Fibers

Answer 10

B. Internodal Pathway

Question 11

Which of the following factors is INCORRECT regarding the cause of the rapid transmission of impulse through the Purkinje fibers?
A. Very high level of permeability of the gap junctions
B. Ions are transmitted easily from on cell to another
C. Very few myofibrils
D. None of these

Answer 11

C. Very few myofibrils

Question 12

Which of the following DOES NOT occur during Ventricular Diastole?
A. Semilunar Valves are closed
B. Atrial Systole
C. Atrial Diastole
D. Atrioventricular Valves are open

Answer 12

A. Semilunar Valves are closed

Question 13

Which of the following subphases of the cardiac cycle Ejection Phase is INCORRECT?
A. First 1/3 of Ejection Phase is the period of slow ejection
B. First 1/3 of Ejection Phase is the period of rapid ejection

Answer 13

B. First 1/3 of Ejection Phase is the period of rapid ejection

Question 14

What happens to the ventricular volume and pressure during Passive Ventricular Filling?
A. Ventricular volume increases, ventricular pressure slightly increases
B. Ventricular volume decreases, ventricular pressure slightly increases
C. Ventricular volume increases, ventricular pressure slightly decreases
D. Ventricular volume decreases, ventricular pressure slightly decreases

Answer 14

C. Ventricular volume increases, and ventricular pressure slightly decreases

Question 15

The pressure that has been built up by the ventricles during isovolumetric contraction that will overcome the pressure in the great vessels?

Question 16

The total quantity of blood that can be stored in a given portion of the circulation for each mmHg pressure rise

Answer 16

Vascular Compliance

Question 17

The efficiency