Technology of storage and primary processing of agricultural products
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Biologiya laboratoriya 2021
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Examples for solving problems .
1. The white color of the pumpkin fruit is represented by the dominant W gene, while the yellow color is represented by the Y gene. The W gene is an epistatic gene and does not cause the Y gene effect. Recessive alleles of these genes give a green color in the form of homozygotes. A. When the two yellow-fruited pumpkins were mixed together, the yellow and green pumpkins were in a 3: I ratio. Identify the genotype of the parent forms. B. If digeterozygous white-fruited pumpkins are cross- bred, what is the separation at F 1 . A. Solution Characters. Genes: yellow y white W; WY-: green wwyy According to the condition of the matter, in order for a yellow fruit to be formed, the genotype must have a dominant Y gene and a homozygous w gene. Therefore, we obtain the genotype of the mixed forms as follows: P wwYy x wwYy Gametes: wY, wy wY, wy F I wwYY, wwYy, wwYy, wwyy Thus, 3 parts yellow I part green pumpkins are formed. B. Solution: We write the configuration scheme: P WwYy x WwYy WY, Wy, wY, wy WY , Wy, wY, wy By placing gametes in the pannet cells , we create combinations of them. Table 9
Thus, individuals with an epistatic dominant gene W in the genotype appear to be white. The development of pumpkin color in the F 2 generation as a result of the epistatic effect of genes . We divide the zygotes in the cells into classes. Genotype: Phenotype: 9-WY- white 3-Wy- white 3-wY- yellow 1-wy- green Such yellow, but recessive genes will be green pumpkins. Download 375.5 Kb. Do'stlaringiz bilan baham: 
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