Question

РЕШИТЬ ЗАДАЧУ СРОЧНО РЕБЯТУШКИ :3Седая прядь волос у человека - доминатный признак. Определить генотипы родителей и детей если известно , что у матери есть седая прядь волос, а у отца нет, а из двух детей в семье один имеет седую пред, а другой нет

Answer 1

S- седая прядь
s - не седая прядь
P матьSs Х отец  ss
G    S, s            s
F1     Ss               ss
        Седая      не седая

Answer 2

Problem Analysis

The problem states that having a gray hair streak is a dominant trait. We need to determine the genotypes of the parents and children based on the given information. The mother has a gray hair streak, the father does not, and one of the two children has a gray hair streak while the other does not.

Solution

To solve this problem, we need to understand the inheritance pattern of the gray hair streak trait. Since the gray hair streak is described as a dominant trait, we can assume that it is controlled by a single gene with two possible alleles: one for the presence of the gray hair streak (dominant allele) and one for the absence of the gray hair streak (recessive allele).

Let's assign the following symbols to represent the alleles: - G: allele for the presence of the gray hair streak (dominant allele) - g: allele for the absence of the gray hair streak (recessive allele)

Based on the given information, we can deduce the following:

1. The mother has a gray hair streak, so her genotype must be either GG or Gg. 2. The father does not have a gray hair streak, so his genotype must be gg. 3. One of the two children has a gray hair streak, while the other does not. This means that one child inherited the dominant allele (G) from the mother, and the other child inherited the recessive allele (g) from both parents.

Let's consider the possible genotypes for the mother and father and determine the genotypes of the children:

1. If the mother is GG and the father is gg, the possible genotypes for the children are: - Child 1: Gg (inherited one G allele from the mother) - Child 2: gg (inherited one g allele from each parent)

2. If the mother is Gg and the father is gg, the possible genotypes for the children are: - Child 1: Gg (inherited one G allele from the mother) - Child 2: gg (inherited one g allele from each parent)

Based on the given information, we cannot determine whether the mother is GG or Gg. Therefore, there are two possible genotypes for the mother and two possible genotypes for each child.

Conclusion

In conclusion, based on the given information, the genotypes of the parents and children can be as follows:

- Possible genotypes for the mother: GG or Gg - Genotype for the father: gg - Possible genotypes for each child: Gg or gg

Please note that the actual genotypes cannot be determined with certainty without additional information or genetic testing.

I hope this helps! Let me know if you have any further questions.