In the DetBrisk plant the synthesis of aqua pigment in the p

In the DetBrisk plant, the synthesis of aqua pigment in the petals is controlled by two genes, B and Q; the WT allele is dominant for both genes. (Unless told otherwise, you can always assume that all other genes in a pathway are homozygous WT in these individuals.) The pathway is... If a pure breeding plant was unable to catalyze the first reaction, what color of petals would you expect to see? If a pure breeding plant was unable to catalyze the second reaction, what color of petals would you expect to see? If the plants from parts a and b were crossed, what color petals will the FI plants have? What would be the expected phenotypic ratios in a cross between F1 plants? Make sure you include phenotypic class information with your ratios.

Solution

The diagram represents that gene B is responsible for producing blue pigment petals from blue pigment. Gene Q is responsible for producing aqua pigment from blue pigment.

A.) If a pure breeding plant was unable to catalyse the first reaction the enzyme controlling the gene B could not function. The pink pigment is expressed in the petals. The pink pigment gets accumulated in the cell.

B.) If a pure breeding plant was unable to catalyse the second reaction the enzyme controlling the gene Q could not function. The blue pigment is expressed in the petals.