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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

AI Generated Solution

The correct Answer is:
### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that females who are homozygous for genes on the X chromosome do not express a trait more markedly than hemizygous males. - In simpler terms, this means that having two identical alleles for a trait in females does not lead to a stronger expression of that trait compared to males who have only one allele (hemizygous). 2. **Understanding the Reason**: - The reason provided is that a dosage compensation mechanism accounts for effective dosage of genes in both males and females. - Dosage compensation is a biological process that balances the expression of X-linked genes between males (who have one X chromosome) and females (who have two X chromosomes). 3. **Analyzing the Assertion**: - In females, one of the X chromosomes is often inactivated (a process known as X-inactivation), which means that even if a female is homozygous for a gene on the X chromosome, the expression of that gene may not be more pronounced than in males who have only one copy of that gene. - Therefore, the assertion is true. 4. **Analyzing the Reason**: - The dosage compensation mechanism ensures that the gene dosage is effectively equalized between males and females. In humans, this is primarily achieved through X-inactivation in females, where one of the two X chromosomes is randomly inactivated. - This means that the expression of X-linked traits is balanced between the sexes, making the reason true as well. 5. **Conclusion**: - Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the correct option is that both statements are true and the reason is a correct explanation for the assertion. ### Final Answer: Both the assertion and the reason are true, and the reason is the correct explanation for the assertion.
### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that females who are homozygous for genes on the X chromosome do not express a trait more markedly than hemizygous males. - In simpler terms, this means that having two identical alleles for a trait in females does not lead to a stronger expression of that trait compared to males who have only one allele (hemizygous). 2. **Understanding the Reason**: - The reason provided is that a dosage compensation mechanism accounts for effective dosage of genes in both males and females. ...
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