In the Visual System, Activation of the Parasympathetic Nervous System

question 37

Multiple Choice

In the visual system, activation of the parasympathetic nervous system causes which of the following?

• A) pupillary constriction and an increase in the refractive power of the lens
• B) pupillary constriction and a decrease in the refractive power of the lens
• C) pupillary dilation and an increase in the refractive power of the lens
• D) pupillary dilation and a decrease in the refractive power of the lens
• E) pupillary dilation and no effect on the refractive power of the lens

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Definitions:

Cerebrospinal Fluid

A clear, colorless body fluid found in the brain and spinal cord, acting as a cushion and providing basic mechanical and immunological protection to the brain.

Choroid Plexus

A network of cells in the ventricles of the brain that produce cerebrospinal fluid.

Ventricle

A chamber of the heart or brain that receives or pumps out blood or cerebrospinal fluid, respectively.

Arbor Vitae

Refers to the treelike appearance of the cerebellar white matter when viewed in cross section, important for the coordination of muscle movements.