Which Is the Most Likely Explanation for the Defect in Dystrophic

question 28

Multiple Choice

Which is the most likely explanation for the defect in dystrophic epidermolysis bullosa, in which the skin blisters in response to any touch?

• A)The skin has too many melanocytes that produce too much melanin.
• B)Melanocytes cannot produce melanin.
• C)Collagen fibrils that attach the epidermis to the dermis break down.
• D)The skin layers are reversed.

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Definitions:

Conduction System

The electrical system within the heart that stimulates contractions to pump blood; includes structures like the SA node and AV node.

Spontaneous Action Potentials

Electrical impulses that occur naturally and are generated by certain cells, such as neurons and muscle cells, without external stimulation.

SA Node

The sinoatrial node is a collection of cells located in the heart's right atrium, responsible for determining the heart's rhythm by creating electrical signals.

AV Node

The atrioventricular node, a part of the electrical conduction system of the heart that coordinates the top of the heart. It plays a crucial role in the control of the heart rate.