Question

Round seed trait (R) is dominant over wrinkled (r) seed trait in Pea. Heterozygous round seeded plant (Rr) is crossed with wrinkled seeded plant (rr). What is the possible progeny?

• A. 302 round : 102 wrinkled
• B. 210 round : 95 wrinkled
• C. 105 round : 99 wrinkled
• D. 103 round : 315 wrinkled

Answer 1

Answer: (C)

105 round : 99 wrinkled

A cross is made between F₁ individual and homozygous recessive individual is called Test cross.

When a heterozygous round seeded plant(Rr) is crossed with homozygous wrinkled seeded plant(rr), in the next generation, 50% progeny are heterozygous round (Rr) and 50% progeny are homozygous wrinkled(rr). The ratio between heterozygous round(Rr) and homozygous wrinkled(rr) is 1:1.It is called Test cross.

So, the correct option is ‘105 round :99 wrinkled’.