Mark's Mother Is Worried Because He Only Sleeps About 4

question 183

Multiple Choice

Mark's mother is worried because he only sleeps about 4 to 5 hours per night. Which of the following would you tell her?

• A)She has reason to be concerned because, in the long run, Mark's lack of sleep will take its toll physically.
• B)There is nothing to worry about because young people need less sleep than older people.
• C)There is no problem as long as Mark spends most of his sleep time in REM sleep.
• D)There is probably nothing to be worried about since different people need differing amounts of sleep.

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Definitions:

Hemophilia

A genetic disorder that impairs the body's ability to make blood clots, leading to excessive bleeding.

Recessive Gene

A gene that produces its characteristic phenotype only when its allele is identical, as opposed to a dominant gene which can express its phenotype over a different allele.

Albinism

A genetic condition characterized by the absence of melanin pigment in the skin, hair, and eyes, resulting in light coloring and increased sensitivity to sunlight.

Recessive

A type of gene that generally does not manifest in the presence of a dominant gene; it requires two copies (one from each parent) for the trait to be expressed.