Question

The contrasting pairs of factors in Mendelian crosses are called:

• A. Allelomorphs
• B. Multiple alleles
• C. Paramorphs
• D. Alloloci

Answer 1

The correct option is A

Allelomorphs

The correct option is A:

Explanation of the correct option:

Allelomorphs:

1. Alleles or allelomorphs refer to the contrasting pairs of factors or traits in the Mendelian crosses.
2. Normally an individual has only two alleles for characters.
3. In the current world, alleles are now understood to be alternative DNA sequences at the same physical locus and they may or may not result in different phenotypic traits.
4. For example at the gene locus for a tall and dwarf character in pea plant and traits for eye color in the fruit fly.

Explanations of the incorrect options:

Option B:

Multiple alleles:

1. Almost always all men daily and characters have only two alternate expressions or have only two alleles.
2. This may not always be true for a gene once having undergone mutation, it may mutate again to give one more altered form and in that case, there will be three alleles.
3. Multiple alleles influence the same character.
4. For example ABO blood grouping in humans.

Option C:

Paramorph is a biological variant that deviates from the mean of the species to which it originally belongs.

Option D:

Alleles located on different loci are called Alloloci.

Final answer: The contrasting pairs of factors in Mendelian crosses are called allelomorphs.