Question

1. Assume alleles of the height gene of corn plants determine the height of the plant's stalks, and that there are two alleles of the gene: "H1" and "H2." Individuals that are homozygous for the "H1" allele are 10 feet in height, individuals that are homozygous for the "H2" allele are 6 feet in height, and heterozygotes for these two alleles are 6 feet in height. From this data, it can be concluded that, with respect to the "H1" allele, the "H2" allele shows ______________________ for height.

A. co-dominance

B. recessivity

C. variable expressivity

D. incomplete dominance

E. dominance

Answer 1

correct answer is Option E- DOMINANCE

REASON:

the gene controlling the height of the corn plant is H ,

The alleles of Gene H are H1 and H2.

homozygous H1 (H1 H1) produces taller corn plant with a height of 10 feet(phenotype)

Homozygous H2(H2 H2) produces a shorter corn plant with a height of 6 feet.(phenotype)

Here, the Heterozygous form (H1 H2) is showing a height of 6 feet , it says that the allele that is dominated here is H2 over the other alelle (H1)

The heterozygous form is showing the character of H2 allele.

So, the dominant allele of the Gene H is H1 and the recessive allele of the Gene H is H1.

Incomplete dominance is the partial dominance of a allele.

Eg: when a red flower is crossed with white flower we, get a pink colored flower.

Here the red color causing Allelel is only partially dominated.

Co - dominance : it is dominance of Both the allele

Eg: ABO blood group

In which the Blood group AB has both A antigen and B antigen suggestive that Both A allele and B allele are dominated.