Question

State the principle of dominance with an illustration.

Answer 1

Mendel proposed the laws of inheritance. The law of dominance states that whenever the dominant allele is present, the dominant allele will express itself. The expression of the recessive allele is suppressed in the presence of dominant allele. The recessive allele does not get lost. The expression remains masked in the progenies of F${}_1$ generation and reappears in the next generation. For example, when pea plants with round seeds (RR) are crossed with plants with wrinkled seeds (rr), all seeds in F${}_1$ generation were found to be round (Rr). When these round seeds were self-fertilised, both the round and wrinkled seeds appeared in F${}_2$ generation in 3: 1 ratio.