In a monohybrid cross between tall pea plants (TT) and short pea plants (tt) a scientist obtained only tall pea plants $(Tt)$ in the $F_1$ generation. However, on selfing the $F_1$ generation pea plants, he obtained both tall and short plants in $F_2$ generation. On the basis of above observations with other angiosperms also, can the scientist arrive at a law ? If yes, explain the law. If not, give justification for your answer.