Which Statement Is True

question 200

Multiple Choice

Which statement is true?

• A) MHC proteins make it possible for T cell receptors to distinguish between self and nonself antigens.
• B) With only six different genetic loci for MHC proteins, humans have a small number of possible allele combinations.
• C) MHC proteins are glycoproteins secreted into the extracellular space and then circulated in the blood.
• D) Different people usually have similar MHC genotypes.
• E) There are five different classes of MHC proteins, each with a slightly different function.

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Definitions:

Delayed Circadian Phase

A shift in the sleep–wake pattern in which adolescents tend to stay up later at night than they did as children and then sleep later in the morning.

Circadian Rhythm

The natural internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours.

NREM Sleep

Non-rapid eye movement sleep, which is a restorative sleep phase that includes deeper, more restful stages of sleep compared to REM sleep.

Kisspeptin

A small protein that is produced by specialized cells in the hypothalamus and plays a key role in the activation of the HPG axis.