The Prevalence of Multiple Sclerosis in Extreme Northern and Southern

question 130

Multiple Choice

The prevalence of multiple sclerosis in extreme northern and southern latitudes suggests that it may be caused by:

• A)an autoimmune reaction.
• B)a lack of vitamin D.
• C)improper blood drainage from the brain.
• D)a viral infection.

Describe the process of olfactory adaptation.

Understand the process of tasting and the structures involved.

Explain how the avascular cornea receives oxygen.

Understand the basic principles of refractive errors in vision and their correction.

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Definitions:

Cilia

Microscopic, hair-like structures on the surface of cells, which move in a wave-like fashion to transport substances.

Cranial Nerves

Nerves that emerge directly from the brain, in contrast to spinal nerves, and are numbered from I to XII, each with specific functions related to senses and movement.

Organ of Corti

The sensory organ located within the cochlea of the inner ear, critical for the process of hearing by converting sound vibrations into neural signals.

Nerve Impulses

Nerve impulses are electrical signals that travel along neurons, facilitating communication within the nervous system.