consider the cross between White petals and dark blue petals Flower color in sweet peas. Sweet peas - is the classic object of genetic research of traits inheritance. When scientists studied the color of flowers of this plant, they discover, that in some crosses the ratio of phenotype was 9:7. That is, from the crossing of two pure lines of sweet peas with white flowers, all plants in first-generation had the purple flowers. And from crossing of these hybrids was obtained the offspring with the phenotypic ratio : 9 purple: 7 white. If the ratio was 3:1, we could suppose, that we are dealing with a simple monohybrid crossing, but in this case the ratio is differ. So obviously, the genetic trait of color of sweet peas flowers is controlled by two nonallelic genes, which interact each other. For convenience, we mark these genes as \"C\" and \"P\". Thus, the pure lines will have genotypes \"CCpp\" and \"ccPP\", and first generation hybrids respectively genotype \"CcPp\". The mechanism of genetic interaction of these genes has become known recently. It was found that the color of sweet pea flowers depends on the synthesis of pigments - anthocyanins. The synthesis of anthocyanins occurs in two stages. Gene \"C\" is responsible for the first stage of the synthesis, while the gene \"P\" for second, and even if only one dominant allele from these genes is lack, then synthesis of anthocyanins is not occurs. That is to say, that the presence of a recessive allele in the homozygous state in the genotype of either of the two genes is blocks the development of trait of flowers coloration. Such interaction of nonallelic genes is called a double recessive epistasis. We can describe this interaction like this - recessive allele of each gene in the homozygous state suppresses the expression of a dominant allele of another ( \"cc\" suppresses \"P\", \"pp\" suppresses \"C\" ). Genetic traits file for this case should be like this : Solution consider the cross between White petals and dark blue petals Flower color in sweet peas. Sweet peas - is the classic object of genetic research of traits inheritance. When scientists studied the color of flowers of this plant, they discover, that in some crosses the ratio of phenotype was 9:7. That is, from the crossing of two pure lines of sweet peas with white flowers, all plants in first-generation had the purple flowers. And from crossing of these hybrids was obtained the offspring with the phenotypic ratio : 9 purple: 7 white. If the ratio was 3:1, we could suppose, that we are dealing with a simple monohybrid crossing, but in this case the ratio is differ. So obviously, the genetic trait of color of sweet peas flowers is controlled by two nonallelic genes, which interact each other. For convenience, we mark these genes as \"C\" and \"P\". Thus, the pure lines will have genotypes \"CCpp\" and \"ccPP\", and first generation hybrids respectively genotype \"CcPp\". The mechanism of genetic interaction of these genes has bec.

1. consider the cross between White petals and dark blue petals
Flower color in sweet peas.
Sweet peas - is the classic object of genetic research of traits inheritance. When scientists studied
the color of flowers of this plant, they discover, that in some crosses the ratio of phenotype was
9:7. That is, from the crossing of two pure lines of sweet peas with white flowers, all plants in
first-generation had the purple flowers. And from crossing of these hybrids was obtained the
offspring with the phenotypic ratio : 9 purple: 7 white. If the ratio was 3:1, we could suppose,
that we are dealing with a simple monohybrid crossing, but in this case the ratio is differ. So
obviously, the genetic trait of color of sweet peas flowers is controlled by two nonallelic genes,
which interact each other. For convenience, we mark these genes as "C" and "P". Thus, the
pure lines will have genotypes "CCpp" and "ccPP", and first generation hybrids respectively
genotype "CcPp". The mechanism of genetic interaction of these genes has become known
recently. It was found that the color of sweet pea flowers depends on the synthesis of pigments -
anthocyanins. The synthesis of anthocyanins occurs in two stages. Gene "C" is responsible for
the first stage of the synthesis, while the gene "P" for second, and even if only one dominant
allele from these genes is lack, then synthesis of anthocyanins is not occurs. That is to say, that
the presence of a recessive allele in the homozygous state in the genotype of either of the two
genes is blocks the development of trait of flowers coloration. Such interaction of nonallelic
genes is called a double recessive epistasis. We can describe this interaction like this - recessive
allele of each gene in the homozygous state suppresses the expression of a dominant allele of
another ( "cc" suppresses "P", "pp" suppresses "C" ). Genetic traits file for this case should
be like this :
Solution
consider the cross between White petals and dark blue petals
Flower color in sweet peas.
Sweet peas - is the classic object of genetic research of traits inheritance. When scientists studied
the color of flowers of this plant, they discover, that in some crosses the ratio of phenotype was
9:7. That is, from the crossing of two pure lines of sweet peas with white flowers, all plants in
first-generation had the purple flowers. And from crossing of these hybrids was obtained the
offspring with the phenotypic ratio : 9 purple: 7 white. If the ratio was 3:1, we could suppose,
that we are dealing with a simple monohybrid crossing, but in this case the ratio is differ. So
obviously, the genetic trait of color of sweet peas flowers is controlled by two nonallelic genes,
which interact each other. For convenience, we mark these genes as "C" and "P". Thus, the

2. pure lines will have genotypes "CCpp" and "ccPP", and first generation hybrids respectively
genotype "CcPp". The mechanism of genetic interaction of these genes has become known
recently. It was found that the color of sweet pea flowers depends on the synthesis of pigments -
anthocyanins. The synthesis of anthocyanins occurs in two stages. Gene "C" is responsible for
the first stage of the synthesis, while the gene "P" for second, and even if only one dominant
allele from these genes is lack, then synthesis of anthocyanins is not occurs. That is to say, that
the presence of a recessive allele in the homozygous state in the genotype of either of the two
genes is blocks the development of trait of flowers coloration. Such interaction of nonallelic
genes is called a double recessive epistasis. We can describe this interaction like this - recessive
allele of each gene in the homozygous state suppresses the expression of a dominant allele of
another ( "cc" suppresses "P", "pp" suppresses "C" ). Genetic traits file for this case should
be like this :