What Is the Best Explanation for a Person Whose Karyotype

question 5

Multiple Choice

What is the best explanation for a person whose karyotype from blood cells shows nearly all cells to have trisomy 21 to have 10 clinical manifestations of Downsyndromeand an above-average intelligence?

• A)The trisomy was a result of nondisjunction of paternal gametes instead of maternal gametes.
• B)The person has pseudo-Down syndrome, in which environmental conditions caused the person to have development that mimics only the physical manifestations.
• C)The person has genomic imprinting, in which the paternal number 21 chromosome is not expressed, and both maternally derived number 21 chromosomes are expressed.
• D)The person has mosaicism of trisomy 21, with blood cells having a high proportion and neurons having a low proportion of cells, with three number 21 chromosomes.

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Definitions:

Botulism

A rare but serious illness caused by botulinum toxin, which can cause paralysis and is often linked to improperly prepared food.

Myelin Sheath

A fatty layer that encases and insulates the axons of neurons, facilitating faster transmission of electrical signals.

Electrical Current

The flow of electric charge through a conductor, typically measured in amperes.

Oxytocin

A hormone involved in social bonding, sexual reproduction, childbirth, and the period after childbirth.