Question: 131: Given below are two statements : one is labelled as
Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Mendel’s law of Independent assortment does not hold good for the genes that are located closely on the same chromosome.
Reason (R): Closely located genes assort independently.
In the light of the above statements, choose the correct answer from the options given below:
(1) (A) is correct but (R) is not correct
(2) (A) is not correct but (R) is correct
(3) Both (A) and (R) are correct and (R) is the correct explanation of (A)
(4) Both (A) and (R) are correct but (R) is not the correct explanation of (A)
Answer: Option (1)
Explanation:
Mendel’s law of independent assortment states that alleles of different genes assort independently during gamete formation.
This law holds true when the genes are located on different chromosomes or are far apart on the same chromosome.
When genes are located closely on the same chromosome, they tend to be inherited together due to linkage.
Therefore, Mendel’s law of independent assortment does not apply to closely linked genes, making Assertion (A) correct.
The Reason (R) states that closely located genes assort independently,
which is incorrect because linked genes do not assort independently.
Hence, Reason (R) is not correct.
Thus, the correct answer is Option (1).