Normal activities of the human heart are regulated:

1. Intrinsically

2. By the autonomic nervous system

3. By the brain stem

4. By the diencephalon

Explain the reason there is a delay in processing the electrical signal from the AV node to the AV bundle. To:

1. allow the atria to complete their contraction prior to ventricular contraction
2. ensure the right and left atria contract at the same time
3. ensure the right and left ventricles contract at the same time
4 prevent an ectopic pacemaker

'Bundle of His' is a part of which one of the following organs in humans?

1. Heart

2. Kidney

3. Pancreas

4. Brain

Which one of the following is a matching pair?

1. Lubb sharp closure of AV valves at the beginning of ventricular systole

2. Dup - sudden opening of semilunar valves at the beginning of ventricular diastole

3. Pulsation of the radial artery - valves in the blood vessels

4. Initiation of the heart beat Purkinje fibres

Ventricular diastole occurs due to a/an 

(1)  Organ system

(2)  Cell organelle

(3)  Tissue

(4)  Organ

Bundle of His includes:

(1) Purkinje fibres + left AV bundle

(2) Purkinje fibres + right AV bundle

(3) Purkinje fibres + right and left AV bundle

(4) SA node + AV node + AV bundle

Which one of the following is wrong with respect to nodal tissue.

1. auto excitable

2. not localized to a single chamber.

3. equal ability to excite throughout nodal tissue.

4. structural changes are observed throughout nodal musculature in different chambers of the heart.

The number of action potential generated by SAN:

1. 70–75 times per minute.

2. 50–72 times per minute.

3. Exact 70 times per minute.

4. not more than 60 times per minute.

The route of action potential in heart is

(1) SA node – AV node – AV bundle

(2) AV node – SA node – bundle of his – AV bundle

(3) SA node – AV node – AV bundle – Bundle of His

(4) SA node – AV node – Purkinje fibres

What does the depolarization of ventricles initiate?

1. Atrial Diastole

2. Atrial systole

3. ventricular systole

4. Joint Diastole