Question

In peas, a pure tall plant (TT) is crossed with a short plant (tt). The homozygous ratio of pure tall plants to short plants in F${}_2$ is

• A. 1 : 3
• B. 3 : 1
• C. 1 : 1
• D. 2 : 1

Answer 1

Answer: (C)

1 : 1

Since, the parents are homozygous tall (TT) and dwarf (tt), the progeny of F${}_1$ generation will be hybrids (Tt). In F${}_2$ generation, the tall and dwarf plants will be produced in 3 : 1 ratio. Out of the three tall plants, one tall plant will be homozygous tall (TT) and two tall plants will be heterozygous tall (Tt). The dwarf plant will be homozygous (tt), as dwarfness is a recessive character. Thus, the ratio between homozygous tall and homozygous dwarf will be 1 : 1.