Question

Drosophila Genetics predictions exercise-L113 (25 pts.) Part I. Meiosis and Punnett Squares Remember, whenever you use Punnett Squares to solve genetics problems, be sure you are completing each of the following steps: 1) Identify the genotypes of the parents. 2) For the specific traits of interest, figure out what kinds of haploid gametes each parent can make. In each gamete, there should be one allele for each trait of interest. If there is more than one trait, make sure all possible combinations of alleles are represented in the resulting gametes 3) For a Pue square, write the gamete genotypes across the top (sperm) and down the left side (eggs) 4) Fill in the Punnett square, making sure all the genotypes are complete and diploid for all traits 5) Determine the genotypic ratios and phenotypic ratios among the offspring Citrus flies, like Drosophila, have 4 different chromosomes (haploid gamete cells are n cells are 2n 8) that might be represented as follows: 4, and diploid somatic Chromosome Pair #1 Chromosome Pair #2 Chromsome Pair #3 Pair #4 (sex chromosomes) Chromosomes #2-4 are autosomes, which are the non-sex chromosomes. Chromosome #1 is the sex chromosome. The above individual has 2"X" chromosomes and is thus a female. Sex determination in citrus flies is similar to that in humans: XX female, XY male. The chromosomes of a male would look like the following: Chromosome Pair #1 (sex chromosomes) Chromosome Pair #2 Chrom some Pair #3 Pair #4

Answer 1