Question

In pea plants tallness is dominant over dwarfness. If a tall plant (TT) is crossed to a dwarf plant (tt), what will be the phenotype and genotype in F1 generation. Give phenotypic and genotypic ratio of F2 generation​

Answer 1

A cross between two pure breeding tall (TT) and dwarf (tt) parent plants produce uniform F

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generation of dominant individuals (Tt). According to the law of dominance, a trait is represented by two contrasting factors of a gene in a heterozygous individual; the allele/factor that can express itself in a heterozygous individual is called as a dominant trait. The another factor whose effect is masked by the presence of dominant factor is called recessive factor. The recessive factor, t, is present in F

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hybrids but its expression is masked by the factor for a dominant trait, T. Thus, all progeny exhibit tallness. If tallness was a recessive trait, it would not have been expressed in heterozygous progeny (Tt). If dwarfism was a dominant trait, the heterozygous progeny (Tt) would have expressed it and was dwarf. Thus, the correct answer is option C.