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Assertion : Phenotypic superiority of hy...

Assertion : Phenotypic superiority of hybrid over either of its parents in one or more traits is termed hybrid vigour.
Reason : Suppression of expression of recessive harmful genes occurs in heterozygotes.

A

If both assertion and reason are 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 bur reason is false.

D

if both assertion and reason are false.

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To solve the assertion and reason question regarding hybrid vigour, we will analyze both the assertion and the reason step by step. ### Step 1: Understand the Assertion The assertion states: "Phenotypic superiority of hybrid over either of its parents in one or more traits is termed hybrid vigour." - **Explanation**: Hybrid vigour, also known as heterosis, refers to the phenomenon where hybrids exhibit traits that are superior to those of their parents. This can include increased growth rate, yield, resistance to disease, and other beneficial characteristics. ### Step 2: Understand the Reason The reason states: "Suppression of expression of recessive harmful genes occurs in heterozygotes." - **Explanation**: In a hybrid, which is typically heterozygous (having two different alleles for a trait), the dominant allele can mask the expression of the recessive allele. This means that harmful recessive traits are less likely to be expressed in the hybrid, contributing to the overall health and vigor of the hybrid organism. ### Step 3: Evaluate the Relationship Between Assertion and Reason Now we need to determine if both statements are true and if the reason correctly explains the assertion. - **Assertion Evaluation**: The assertion is true because hybrid vigour does refer to the superior traits of hybrids compared to their parents. - **Reason Evaluation**: The reason is also true as it accurately describes a mechanism (suppression of recessive harmful genes) that contributes to hybrid vigour. ### Step 4: Conclusion Since both the assertion and the reason are true, and the reason provides a correct explanation for the assertion, we conclude that the correct option is: **Option A: Both assertion and reason are true, and the reason is the correct explanation of the assertion.** ---
To solve the assertion and reason question regarding hybrid vigour, we will analyze both the assertion and the reason step by step. ### Step 1: Understand the Assertion The assertion states: "Phenotypic superiority of hybrid over either of its parents in one or more traits is termed hybrid vigour." - **Explanation**: Hybrid vigour, also known as heterosis, refers to the phenomenon where hybrids exhibit traits that are superior to those of their parents. This can include increased growth rate, yield, resistance to disease, and other beneficial characteristics. ### Step 2: Understand the Reason ...
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