Question

Crossing over takes place between:

• A. Non-sister chromatids of non-homologous pair
• B. Non-sister chromatids of homologous pair
• C. Sister chromatids of homologous pair
• D. Sister chromatids of non-homologous pair

Answer 1

The correct option is B Non-sister chromatids of homologous pair

Crossing over is the exchange of genetic material between non-sister chromatids of two homologous chromosomes. During the pachytene stage, the four chromatids of each bivalent chromosome becomes distinct and clearly appears as tetrads. This stage is characterized by the appearance of recombination nodules, the sites at which crossing over occurs.