Need help please don't understand these questions.
Dihybrid Genetic Crosses for Corn.
A. What are the two hypotheses that you made about the allelic frequencies of progeny produced by the crosses:
P x P? P
F1 x F1? F
B. Based on what you know about phenotypes and Figure 2, for the P generation, what is the corn plant genotype on each cob containing the P corn kernels? One is completely dominant, so its genotype is ________?
One is completely recessive, so its genotype is_______? .
C. Would it make a difference in the outcome of this cross if the genotype of one parent is PPss and the other is ppSS?
D. From the phenotype of the kernels on each P generation cob what would the predicted genotype of any F1 plant be?
E. Given the 2n equation predict how many different genetic outcomes will be possible from an
F1 cross resulting in the F2 generation in a dihybrid corn cross.
F. If a F2 corn cob resulting from this F1 cross contained 563 seeds, how many of the seeds would you expect to look like the F1 parent?
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A. In a dihybrid genetic cross, you are studying the inheritance patterns of two different traits, each controlled by two different alleles. The first hypothesis you made about the allelic frequencies in the progeny produced by the crosses is regarding the P x P cross. The second hypothesis is about the F1 x F1 cross. However, the information provided does not specify what those hypotheses are. To answer this question, you need to state your own hypotheses based on the given information about the crosses.
B. Based on the information about phenotypes and Figure 2, you need to determine the genotypes of the corn plants in the P generation. One cob contains corn kernels that exhibit complete dominance, meaning one allele completely masks the expression of the other. This implies that the genotype of the corn kernels on that cob would be homozygous dominant. The other cob contains corn kernels that are completely recessive, so the genotype of those kernels would be homozygous recessive.
C. The genotype of one parent being PPss and the other being ppSS would indeed make a difference in the outcome of the cross. This is because the allele combinations would be different, potentially leading to different phenotypic ratios in the offspring.
D. To determine the predicted genotype of any F1 plant based on the phenotype of the kernels on each P generation cob, you would need to know the genotypes of the P generation plants. Since the genotypes of the P generation plants are not provided in the information given, it is not possible to determine the predicted genotype of any F1 plant.
E. Given the 2n equation, where n stands for the number of different traits being studied, you can determine how many different genetic outcomes would be possible in the F2 generation of a dihybrid corn cross. In this case, since you are studying two traits (dihybrid), the equation would be 2^2 = 4. Therefore, there would be four different genetic outcomes possible in the F2 generation.
F. If an F2 corn cob resulting from an F1 cross contained 563 seeds, it is not possible to accurately determine how many of those seeds would look like the F1 parent without additional information. To make predictions about the phenotypic ratios, you would need to know the genotypes of the parents and the type of inheritance pattern for each trait being studied.