Question

In a plant species, yellow seed colour (Y) is completely dominant over white (y). A genetic cross between plants with yellow seeds and plants with white seeds yielded a progeny of 48 yellow-seeded and 52 white-seeded plants. The genotypes of the yellow-seeded and white-seeded parent plants, respectively, are most likely to be

• A. YY and yy
• B. Yy and yy
• C. Yy and Yy
• D. YY and Yy

Hint:

A 1:1 ratio in monohybrid cross always indicates a test cross between a heterozygote and a recessive parent.

Answer 1

The Correct Option is B

Step 1: Analyze the given data.
The progeny consists of approximately 1:1 ratio (48:52) of yellow to white seeds. This indicates a monohybrid test cross.
Step 2: Determine parental genotypes.
When a heterozygous yellow (Yy) plant is crossed with a homozygous recessive white (yy) plant, the progeny ratio is 1 yellow : 1 white.
Step 3: Conclusion.
Therefore, the genotypes of the yellow-seeded and white-seeded parents are Yy and yy, respectively.