At what point in cell division is a chromosome lost so that, after fertilization with a normal gamete, the result is an embryo with 45,X?
A) after an error occurring in anaphase I or anaphase II
B) after an error occurring in anaphase I only
C) after an error occurring in anaphase II only
D) after an error occurring in prophase I only
E) after an error occurring in metaphase II only

Question

Quizplus · Accepted Answer

An error in anaphase I or anaphase II can lead to nondisjunction, resulting in gametes with missing or extra chromosomes. If a gamete missing a sex chromosome (X or Y) fertilizes a normal gamete, it can result in a 45,X embryo, which is Turner syndrome.

At What Point in Cell Division Is a Chromosome Lost