Question

Crossing over occurs between ________chromatid of _______chromosome.

• A. Sister, homologous
• B. Non-sister, homologous
• C. Sister, non homologous
• D. Non- sister, Non - homologous

Answer 1

Answer: (B)

Crossing over is the exchange of chromosomal segment between non-sister chromatids of homologous chromosomes. It occurs during pachytene of prophase-I of meiosis, and it results in recombination of genes, producing genetic variation. It is carried out by enzyme recombinase.