Question

Помогите срочно!у растения ночная красавица красная окраска цветков не полностью доминирует над белой окраской. гетерозиготные особи по этому признаку имеют розовую окраску. определите фенотипы исходных организмов, а также генотипы и фенотипы потомства при скрещевании 1) Аа х Аа 2) АА х аа 3) Аа х АА 4) Аа х аа

Answer 1

    Aa x Aa
G Aa    Aa
F AA Aa Aa aa
25% белые 25% красные и 50 % розовую

Answer 2

Phenotypes and Genotypes of the Parent Organisms

The plant in question is the "night-blooming cereus" or "Queen of the Night," known for its striking red and white flowers. When considering the color of the flowers, the red color is not fully dominant over the white color, resulting in heterozygous individuals having a pink coloration.

1) Parent Organisms: Aa x Aa - Phenotypes: The parent organisms have a red and white flower coloration, respectively. - Genotypes: Both parent organisms have the genotype Aa, representing the heterozygous condition for the flower color gene.

2) Parent Organisms: AA x aa - Phenotypes: The first parent has red flowers, while the second parent has white flowers. - Genotypes: The first parent has the genotype AA, representing homozygous dominant for red flowers, and the second parent has the genotype aa, representing homozygous recessive for white flowers.

3) Parent Organisms: Aa x AA - Phenotypes: The first parent has a red and white flower coloration, while the second parent has red flowers. - Genotypes: The first parent has the genotype Aa, representing the heterozygous condition for the flower color gene, and the second parent has the genotype AA, representing homozygous dominant for red flowers.

4) Parent Organisms: Aa x aa - Phenotypes: Both parent organisms have a red and white flower coloration, respectively. - Genotypes: The first parent has the genotype Aa, representing the heterozygous condition for the flower color gene, and the second parent has the genotype aa, representing homozygous recessive for white flowers.

Offspring's Genotypes and Phenotypes

When these parent organisms are crossed, the following genotypes and phenotypes can be expected in the offspring:

- In the first case (Aa x Aa), the offspring will have a phenotypic ratio of 1:2:1 for red:pink:white flowers, and a genotypic ratio of 1:2:1 for AA:Aa:aa. - In the second case (AA x aa), all offspring will have the genotype Aa and the phenotype for red flowers. - In the third case (Aa x AA), the offspring will have a phenotypic ratio of 1:1 for red:white flowers, and a genotypic ratio of 1:1 for Aa:AA. - In the fourth case (Aa x aa), the offspring will have a phenotypic ratio of 1:1 for red:white flowers, and a genotypic ratio of 1:1 for Aa:aa.

Understanding the genetic principles behind flower color inheritance can provide valuable insights into plant breeding and genetics. If you have further questions or need additional assistance, feel free to ask!