Question
Biology Question on Meiosis
The exchange of segments of non-sister chromatids between chromosomes of a homologous pair is termed as
A
transformation
B
translocation
C
crossing over
D
chromosomal aberration
Answer
crossing over
Explanation
Solution
During pachytene stage of meiosis-I, the chromosomes become bivalent (tetrad) in the beginning, ie, each chromosome with two chromatids and four arms. Then, non sister chromatids of homologous chromosomes exchange segments between themselves. This exchange of segment is called crossing over. Crossing over is supposed to begin in late pachyteiie and completed in early diplotene.