Question

1. what molecular conformation (structure) of homologous chromosomes facilitates crossing over?

meiosis ii
triads
mitosis
tetrad

Explanation:

Cross - over occurs during meiosis I when homologous chromosomes pair up. A tetrad is formed by the pairing of a homologous chromosome pair (two chromosomes, each with two sister chromatids), and it is this structure that facilitates crossing - over. Meiosis II does not involve the initial pairing for crossing - over. Mitosis is a different type of cell division not related to crossing - over in this context. Triads are not relevant to the molecular conformation for crossing - over.

Answer:

D. tetrad