Question

Which of the following crosses will give only recessive progeny in ${\text{F}}_1$ generation?

• A. TT x tt
• B. Tt x tt
• C. tt x tt
• D. TT x TT

Answer 1

The correct option is C tt x tt

The cross between tt x tt will give only recessive progeny in $F_1$ generation because both the parents produce only recessive trait (t) in gametes and the resultant progeny will always be recessive in the $F_1$ generation (as given below).

In TT x tt, only dominant progeny will be produced in the $F_1$ generation which will be of the genotype Tt (as given below).

In Tt x tt cross, both dominant and recessive progeny will be produced in the $F_1$ generation in the ratio, 1:1 (as given below).

Only dominant progeny will be produced in the $F_1$ generation in the cross between TT x TT (as given below).