Problem:
You are performing crosses between two mice that are both heterozygous (D1D2) for a mutation in the centromere region. Assume that the D1 allele is found in 90% of eggs produced by heterozygous females, but that sperm produced by heterozygous males exhibit the normal 1:1 ratio of D1 to D2 genotypes.
Question 1: Which of Mendel's rules is violated by the pattern of transmission exhibited by heterozygous females? Briefly explain why.
Question 2: What genotypic segregation ratio will this monohybrid cross produce? Show your calculations but no written explanation is necessary.
Question 3: Explain why it is biologically reasonable to imagine that a mutation in the centromere would alter the genotype ratios in oogenesis but not in spermatogenesis.
Please provide discription of all the answers.