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​The following figure represents a physical map and a genetic map for 5 different genes (a to e).​​Which one of the following statements based on the
Question

The following figure represents a physical map and a genetic map for 5 different genes (a to e).

Which one of the following statements based on the above is correct?

A.

The region between b and c is more recombinogenic than the other loci.

B.

In comparison to the region between a and b, the region between d and e is more recombinogenic.

C.

1 cM is equal to ~1 Kb.

D.

If more markers were mapped between d and e, the genetic distance between d and e is likely to decrease.

Correct option is B

Explanation-

Step-by-step Interpretation:
Look at the physical map:
It shows how far genes are physically apart on the DNA molecule, measured in Kb.
Example from the figure:
a to b = 10 Kb
b to c = 20 Kb
d to e = 10 Kb, etc.
Look at the genetic map:
It shows how frequently recombination occurs between those genes, measured in cM. Recombination happens during meiosis and helps us understand genetic linkage.
Example from the figure:
a to b = 9 cM
b to c = 2 cM
d to e = 20 cM
Calculate recombination rate:
Use the formula:

Recombination rate=Genetic distance (cM)Physical distance (Kb)\text{Recombination rate} = \frac{\text{Genetic distance (cM)}}{\text{Physical distance (Kb)}}

​This tells you how much recombination happens per kilobase of DNA.
Compare rates:
    Higher cM/Kb = more recombination per unit DNA = more recombinogenic
    Lower cM/Kb = less recombination = less recombinogenic

Example from the question:
Region  and  its recombination Rate (cM/Kb)
a–b  :  0.9
b–c  :  0.1
c–d :  1.1
d–e  :  2.0 ← highest

Final Answer

​The region between d and e shows the highest recombination rate (2.0 cM/Kb), making it the most recombinogenic. This is more than the a–b region (0.9 cM/Kb), so the correct interpretation is that d–e is more recombinogenic than a–b, which matches Option b.

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