Question

What will be the percentage of gametes having recessive alleles for both the genes, if produced by a plant with genotype TtRr?

• A. 50%
• B. 30%
• C. 12.5%
• D. 25%

Answer 1

The correct option is D 25%

Plants having genotype TtRr produce 4 different kinds of gametes.TR, Tr, tR, tr.
TtRr
↓
Gametes: TR, Tr, tR, tr
One of the four gametes carry recessive alleles for both the characters (tr).
Hence, the percentage of gametes with two recessive alleles is ¼ x 100% = 25%.