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Assertion : Females, homozygous for gene...

Assertion : Females, homozygous for genes on the X chromosomes do not express a trait more markedly than do hemizygous males
Reason: Dosage compensation mechanism accounts for effective dosage genes in males and females.

A

If both assertion and reason is true and reason is the correct explanation of assertion

B

If both assertion and reason are true but reason is not the correct explanation of assertion

C

If assertion is true but reason is false

D

If both assertion and reason is false

Text Solution

Verified by Experts

The correct Answer is:
A
Female have two X chromosomes and males have only one X chromosome. Thus, a dosage compensation mechanism must be present through which the effective dosage of genes of the two sexes is made equal. This is achieved by inactivation of one X chromosome in females which gets condensed and become heteropyknotic. Since only one X chromosome is required for normal metabolision in cells of females, the other X chromosome has the capability in others, Thereforem dosage compensation regulates the enzyme level of males and females.
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