The Colored Part of the Eye Which Contains Muscles to Contract

question 143

Multiple Choice

The colored part of the eye which contains muscles to contract or expand the pupil is the __________.

• A)lens
• B)fovea
• C)iris
• D)cornea

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Definitions:

Basal Ganglia

A group of nuclei in the brain involved in coordinating movement as well as learning, behavior, and emotions.

Corticospinal Tract

A pathway in the central nervous system that conducts impulses from the brain to the spinal cord, controlling voluntary muscle movements.

Extrapyramidal Tract

A network of neurons in the brain involved in the coordination and control of motor functions, particularly those responsible for involuntary movements.

Myelin

A fatty substance that encases and insulates nerve fibers, speeding up electrical impulses between neurons and crucial for proper nervous system functions.