What Factors Are Most Responsible for the Increasing Length of Life

question 22

Multiple Choice

What factors are most responsible for the increasing length of life of Americans over the past 100 years?

• A)Better nutrition and family planning options
• B)Education concerning the need to reduce salt and fat in the diet
• C)Improved medical care,including exciting new technologies
• D)More efficient cancer screenings and early intervention

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Definitions:

Gray Matter

Nervous tissue in the brain and spinal cord that contains cell bodies, dendrites, and unmyelinated axons. Compare with white matter

White Matter

Nervous tissue in the brain and spinal cord that contains myelinated axons. Compare with gray matter.

Myelinated Axons

Myelinated Axons are nerve fibers covered by a myelin sheath, which insulates the axon and increases the speed of nerve impulse transmission, crucial for efficient functioning of the nervous system.

Unmyelinated Axons

Unmyelinated Axons are nerve fibers that lack a myelin sheath, resulting in slower transmission of nerve impulses compared to myelinated axons, commonly found in the autonomic nervous system.