Question

A cross of two pure breeding lines of lentils, one with spotted seeds and the other dotted seeds, results in hybrid offspring whose seeds have both spots and dots. The alleles for seed color pattern exhibit _____________.

- complete dominance
- co-dominance
- incomplete dominance
- recessiveness

Answer 1

In the given scenario with lentil seeds, the pattern of inheritance exhibited is co-dominance, where both the spotted and dotted alleles are equally expressed in the hybrid plants.

Step-by-step explanation:

The alleles for seed color pattern exhibited by the lentils in the question show co-dominance. This means that both spotted and dotted patterns are equally expressed in the hybrid offspring, rather than one being dominant over the other. This is similar to the blood type MN system in humans, where alleles M and N are both expressed in the phenotype of the heterozygote. The phenotypic ratio expected from a self-cross would be distinct for each genotype while maintaining the Mendelian genotypic ratio of 1:2:1 as seen in the MN blood group example.