Question

X-ray .............. the frequency of crossing over.

• A. Increases
• B. Decreases
• C. Gradually increases
• D. None of the above

Answer 1

Answer: (A)

Increases

There are certain factors which change the rate of crossing over. Temperature changes, shock and radiation exposure can result in a change in the frequency of crossing over. When the cells are exposed to X-rays, the genetic material gets mutated due to the radiations. This radiation also affects the stability of the chromosomes which increases the chances of crossing over.

Thus, the correct answer is option A.