Question

How do Mendel's experiments show that traits may be dominant or recessive?

Answer 1

Mendel crossed pure-bred tall pea plants with pure-bred dwarf pea plants and found that only tall pea plants were produced in the F₁ generation. From this, Mendel concluded that the F₁ generation showed the traits of only one of the parents: tallness. The trait of other parent plant, dwarfness, did not show in the progeny of the first generation. When tall pea plants of the first generation were crossed, then in F₂generation, tall plants and dwarf plants were obtained in the ratio 3:1.
From these experiments, Mendel concluded that the trait for dwarfness of one of the parent pea plant had not been lost. It was merely concealed or suppressed in the first generation to reemerge in the second generation.