The prophase I stage of meiosis plays a vital role in r-DNA formation. Justify with reason.
Recombination or crossing over is occurring in the pachytene stage of Prophase 1 of Meiosis 1. Hence some part of chromosomes gets exchanged.
r-DNA molecules are formed by the joining together of DNA molecules from different sources. Thus, prophase stage 1 contributes to r-DNA formation.
The following diagram shows how a crossover takes place.