Question

chromosomal inheritance: when does nondisjunction occur
nondisjunction that results in abnormal number of chromosomes can occur during
multiple choice
metaphase ii.
telophase i.
anaphase i or ii.
prophase i.
anaphase of mitosis.

Explanation:

Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate properly during cell division. In meiosis, it can occur in anaphase I (failure of homologous chromosomes to separate) or anaphase II (failure of sister chromatids to separate). Metaphase II is about chromosome alignment, telophase I is about cell division completion, prophase I is about chromosome pairing and crossing - over, and anaphase of mitosis (though nondisjunction can occur here, the question is likely focused on meiosis as it's about chromosomal inheritance in the context of the question's title which is more related to sexual reproduction - based inheritance where meiosis occurs).

Answer:

anaphase I or II.