Which of the Following Is a Chronic Disease of the Central

question 8

Multiple Choice

Which of the following is a chronic disease of the central nervous system that involves progressive destruction of the myelin sheaths of the neurons?

• A) Multiple sclerosis
• B) Myasthenia gravis
• C) Parkinson disease
• D) Retinopathy

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Definitions:

Scales

Small, rigid plates forming the outer skin covering in fish and reptiles, serving as protection and support.

Cork Cambium

A type of meristem found in the bark of plants that produces cork cells to provide protection and reduce water loss.

Periderm

A protective outer layer of tissue in plants, replacing the epidermis in parts of the stems and roots, consisting of the cork, cork cambium, and phelloderm.

Xylem

The vascular tissue in plants responsible for the conduction of water and nutrients from the roots to the leaves and other parts.