In tomatoes, the gene that determines the red color of the fruit is dominant over the gene for the yellow color.

In tomatoes, the gene that determines the red color of the fruit is dominant over the gene for the yellow color. The 3021 tomato bush obtained from hybrid seeds had a yellow color, and 9114 had a red color. How many heterozygous plants are among the first generation hybrids?

As you can see, the ratio of yellow and red tomatoes is 1: 3. Such a ratio, according to Mendel’s second law, can be obtained provided that both parents were heterozygous for color:

1) Aa x Aa;

In this situation, the following variants of genotypes can be obtained:

2) AA, Aa, Aa, aa;

As you can see, the number of heterozygotes is 50% or 2/3 of the number of all red tomatoes. Let’s count their number:

3) 9114 * (2/3); or write in this form (9114/3) * 2

4) Answer: 6076