Refer to the Figure and Table Below

question 187

Multiple Choice

Refer to the figure and table below. Vitamin B₁₂ is an essential vitamin that humans must acquire from their diets.Within the small intestine, vitamin B₁₂ is taken up by receptor-mediated endocytosis as shown in the figure.The protein labeled IF binds to vitamin B₁₂ molecules in the intestinal lumen, forming a complex.This complex is recognized by the IF receptor present on intestinal cells and stimulates endocytosis when it binds.Vitamin B₁₂ by itself does not bind to the receptor.Individuals known to carry a mutation in either the IF protein or the IF receptor are represented in the table, along with observations about whether symptoms of vitamin B₁₂ deficiency are present.If a drug molecule could be produced that would bind to vitamin B₁₂ and stimulate uptake by intestinal cells, which individual(s) would be expected to benefit, based on the information given?

• A) Individual 1 only
• B) Individual 2 only
• C) Individual 3 only
• D) Individuals 1 and 2 only
• E) Individuals 2 and 3 only

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Definitions:

Sexual Activity

Behaviors that include or are driven by sexual motives, encompassing a range of actions from intimacy to intercourse.

Sexual Scripts

Socially learned behaviors and patterns regarding sexual interactions and expectations.

Nongenital Activities

Activities or behaviors that do not involve the sexual organs, often referring to forms of intimacy or physical closeness that are not sexual in nature.

Gender

The range of characteristics pertaining to, and differentiating between, masculinity and femininity, often based on societal norms and individual identity.