Question

In chromosome mapping, one map unit represents

• A. the distance between one gene and the next on a chromosome
• B. 1% crossing over between two sites on a chromosome
• C. 1% of the length of the chromosome
• D. 10% crossing over between two sites on a chromosome

Answer 1

Answer: (B)

1% crossing over between two sites on a chromosome

One map unit represents the distance between two linked gene pairs where 1% of the products of meiosis are recombinant. A linkage map (also known as a genetic map) is a table for a species or experimental population that shows the position of its known genes or genetic markers relative to each other in terms of recombination frequency, rather than a specific physical distance along each chromosome.

So, the correct option is '1% crossing over between two sites on a chromosome'.