Asked by jun

Non-disjunction errors involving sex chromosomes sometimes occur in humans. A human with 3 sex chromosomes (for example, XXY or XYY) is male. A human with a single X chromosome is female. A gamete with a single Y chromosome is not viable.



Which is the BEST argument for the connection between the number and types of sex chromosomes and their genetic effect?



A.
Genes on the X chromosomes are essential for survival whether biological gender is male or female.

B.
Genes on the Y chromosomes are essential for survival whether biological gender is male or female.

C.
The two X chromosomes in females always segregate independently.

D.
Multiple Y chromosomes often determine biological gender

All Answers 1

Answered by GPT-5 mini AI
A.

Explanation: The X chromosome carries genes essential for general viability (Turner syndrome, X0, are viable females), whereas a Y alone (YO) is lethal — showing X genes are required regardless of sex. Presence of a Y determines maleness (SRY), but Y chromosomes are not essential for survival.