If a pair of homologous chromosomes fails to separate during meiosis I, select the choice that shows the chromosome number of the four resulting gametes with respect to the normal haploid number (n)?
A) n + 1; n + 1; n - 1; n - 1
B) n + 1; n - 1; n; n
C) n + 1; n - 1; n - 1; n - 1
D) n + 1; n + 1; n; n

Question

Quizplus · Accepted Answer

This phenomenon is known as nondisjunction, and when it occurs during meiosis I, it results in two gametes having an extra chromosome (n + 1) and two gametes missing a chromosome (n - 1).

If a Pair of Homologous Chromosomes Fails to Separate During