Question

Assertion (A): Alleles are alternative forms of a gene.

Reason (R): Alleles control two traits of a character.

A. if A and R true and Ris correct explanation of A
B. if A and R is true and Ris not correct explanation of A
C. if A is true but Ris false
D. if A is false but R is true​

Answer 1

Alleles are alternative forms of a gene, confirming the assertion (A) as true. Genetic variation arises from multiple alleles existing within a population. The most common phenotype or genotype is deemed the wild type, with all others being variants.

Step-by-step explanation:

Alleles are indeed alternative forms of a gene, which implies that the assertion (A) in the question is true. However, the relationship between alleles and multiple alleles at the population level is more complex than Mendel’s initial postulate of one dominant and one recessive allele per gene.

Genetic variation within a population comes from the presence of multiple alleles. An individual can only have two alleles for a particular gene, but, across a population, many different alleles for that same gene could exist. This contributes to the rich diversity of genotypes and phenotypes observed.

The most common form of a phenotype or genotype is referred to as the wild type, and any other variants are considered mutants or variants. These mutant alleles can be either recessive or dominant to the wild-type allele. Understanding the concept of multiple alleles is crucial for grasping how traits are passed down through generations beyond the simplistic dominant/recessive model.