Page 426 - Atlas of Histology with Functional Correlations

D. having little glycogen in their cytoplasm.

E. containing granules in their cytoplasm.

3. What causes the release of atrial natriuretic hormone (ANH)?

A. Decreased blood volume in the atrium

B. Decreased heart rate

C. Decreased blood pressure

D. Stretching or distention of the atrium

E. Stretching or distention of the ventricle

4. The main function of atrial natriuretic hormone (ANH) is to:

A. increase blood flow into the atrium.

B. increase blood pressure.

C. reduce atrial distention.

D. reduce ventricular distention.

E. decrease pacemaker activity.

5. The sinoatrial (SA) and atrioventricular (AV) nodes are composed of:

A. motor or efferent neurons.

B. sensory or afferent neurons.

C. the axon terminals of the autonomic nervous system.

D. unipolar ganglion cells.

E. modified cardiac muscle fibers.

ANSWERS

1. Correct Answer: D. Atrioventricular bundle. This bundle divides into right
and left bundle branches to stimulate both ventricles to contract.

2. Correct Answer: D. Having little glycogen in their cytoplasm. Purkinje
fibers also have fewer contractile elements.

3. Correct Answer: D. Stretching or distention of the atrium. This action
causes the release of ANH that results in decreased blood pressure and
blood volume, reducing the distention of atrial wall.

4. Correct Answer: C. The main function of ANH is to reduce atrial

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