In a monohybrid cross between tall pea plants denoted by TT

In a monohybrid cross between tall pea plants denoted by TT and short pea plants denoted by tt, SehajAnant obtained only tall plants denoted by Tt in the $F_{1}$ generation. However, in $F_{2}$ generation she obtained both tall and short plants. Using the above information explain the law of dominance.

According to the law of dominance, trait that is dominant gets expressed in the $F_{1}$ generation. Although both the dominant and the recessive traits get inherited, in the $F_{1}$ generation, it is only the dominant trait which gets expressed, i.e., a single copy of dominant trait is enough for the expression of the tall trait. Trait like ‘T’ is thus called dominant trait.