Question

In an experiment you introduce a pair of unpaired homologous chromosomes into pachytene stage, what will you expect to observe?

(a) Pairing and subsequent recombination

(b) Pairing will occur but no recombination

(c) No pairing will occur but recombination will take place

(d) Neither pairing nor recombination

I have been asked this question in an internship interview.

I would like to ask this question from Meiosis Prophase 1 : Pachytene topic in chapter Chromosomal Changes During Meiosis of Cytogenetics

Answer 1

The correct choice is (d) Neither pairing nor recombination

Easiest explanation: There is no additional pairing or synaptonemal complex formation at the pachytene stage. Thus, the introduced chromosomes will neither pair, and in absence of it no recombination will occur.