Match the column I with that of their explanation in column II and select the correct option.
Column I | Column II |
a. Dominance | 1. In heterozygous condition both alleles express to create a mixed phenotype |
b. Codominance | 2. More than two alleles for a gene controlling a single character |
c. Multiple allelism | 3. Two alleles in a heterozygote create an intermediate phenotype |
d. Incomplete dominance | 4. In a heterozygous condition only one allele expresses itself |
a - 4 b - 1 c - 2 d - 3
Each gene in an individual has two contrasting factors called alleles. Out of two alleles one will be superior in expressing their characters (dominant) whereas the other allele will be able to express only in homozygous condition (recessive).
Codominance is a form of inheritance in which alleles of a gene, when they come together in heterozygous condition are fully expressed. As a result of this inheritance, offspring will show a mixture of the parental phenotypes.
Multiple allelism is the non-mendelian inheritance where there are more than two alleles for a gene that controls the character. Human ABO blood group system is the best example of multiple allelism.
The phenomenon in which two true-breeding parents crossed to produce an intermediate offspring is called incomplete dominance. In this case, none of the alleles of a gene is dominant; the phenotype of a heterozygous individual is a intermediate of the two contrasting traits.