Question 8
With the help of the Mendel’s monohybrid cross explain the term dominant and recessive.
Answer
In Mendel’s monohybrid cross, two pea plants with contrasting traits, one with dominant and other with recessive traits, were crossed. The offspring produced in the F1 generation showed only the dominant trait. This indicates that the dominant trait is expressed over the recessive trait in the offspring. When these F1 plants were self-pollinated or cross-pollinated with another F1 plant, the F2 generation was produced. In this generation, the ratio of dominant to recessive traits was 3:1. This shows that the recessive trait is not expressed in the F1 generation but is present in the genes, and it can reappear in the F2 generation. Thus, the dominant trait is expressed over the recessive trait in heterozygous individuals. The trait that is expressed in the presence of its contrasting trait is called a dominant trait, while the trait that is not expressed in the presence of its contrasting trait is called a recessive trait.
