In pea plants, yellow seeds are dominant to green.If a heterozygous yellow seeded plant is crossed with a green seeded plant, what ratio of yellow and green seeded plants would you expect in F1 generation :a)50 : 50b)9 : 1c)1 : 3d)3 : 1Correct answer is option 'A'. Can you explain this answer?

Question

Answer

Correct Answer Is Option 'A' .
In Mendel's dihybrid cross, the F2 progeny contain 9:3:3:1 ratio,in which there are - 9 Round yellow, 3 wrinkled yellow, 3 round green, 1 wrinkled green ;

12 - yellow , 4 - green

yellow: green = 3 : 1

Answer

Introduction:
In pea plants, the color of the seeds is determined by a single gene. The gene for yellow seeds (Y) is dominant over the gene for green seeds (y). When a heterozygous yellow seeded plant (Yy) is crossed with a green seeded plant (yy), the offspring in the F1 generation will exhibit a certain ratio of yellow and green seeded plants.

Punnett Square:
To determine the ratio of yellow and green seeded plants in the F1 generation, we can use a Punnett square. The Punnett square is a simple diagram used to predict the possible genotypes and phenotypes of offspring in a genetic cross.

In this case, the heterozygous yellow seeded plant (Yy) can produce two types of gametes: Y or y. The green seeded plant (yy) can only produce one type of gamete: y. Therefore, the Punnett square for this cross would look like this:

| Y | y
--------------
Y | YY | Yy
--------------
y | Yy | yy

The genotypes in the resulting F1 generation are YY, Yy, Yy, and yy. However, since yellow seeds (Y) are dominant over green seeds (y), both the YY and Yy genotypes will result in yellow seeds. Therefore, the phenotypic ratio of yellow to green seeded plants in the F1 generation is 3:1.

Explanation of Answer:
The correct answer to this question is option 'A', which states that the ratio of yellow to green seeded plants in the F1 generation is 50:50. This answer is incorrect.

The correct ratio is 3:1, as explained above. The ratio of 50:50 (option 'A') suggests that both yellow and green seeds are equally likely in the F1 generation, which is not the case since yellow seeds are dominant.

Therefore, option 'A' is incorrect and option 'D' (3:1) is the correct answer.

Conclusion:
When a heterozygous yellow seeded pea plant is crossed with a green seeded plant, the expected ratio of yellow to green seeded plants in the F1 generation is 3:1. Yellow seeds are dominant over green seeds in pea plants, so the majority of the offspring will have yellow seeds.

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