1. Imagine that you as a fruit fly researcher cross truebreeding, wild-type flies to true breeding, eyeless flies in the Pgeneration. The resulting F1 generation is made up of 100%wild-type flies with normal eyes. Based on Mendelian genetics, whatphenotype ratio would you expect to see for a F1 monohybrid cross?How would you go about determining the genotype ratio in the F2generation?
2. In cactus, the relationship between Gene S and Gene Nis known to be epistatic. Gene S controls the sharpness of spinesin a type of cactus. Cacti with the dominant allele, S, have sharpspines, whereas homozygous recessive ss cacti have dull spines. Atthe same time, the second gene, N, determines whether or not cactihave spines. Homozygous recessive nn cacti have no spines at all.Briefly explain why this genetic interaction is consideredepistasis. Which gene is considered epistatic to theother?
3. In Drosophila melanogaster, vestigial wingsare determined by a recessive allele of a gene that is linked to agene with a recessive allele that determines black body color. T.H. Morgan crossed black-bodied, normal-winged females andgray-bodied, vestigial-winged males. The F1 were all gray bodied,normal winged. The F1 females were crossed to homozygous recessivemales to produce testcross progeny. Morgan calculated the mapdistance to be 17 map units. Which of the phenotypes used in theexperiment would be considered parental? Which phenotypes would berecombinants? What would be the percentages of the resultingphenotypes of the testcross progeny?
4. The most commonly occurring mutation in people withcystic fibrosis is a deletion of a single codon. What is the resultof this type of mutation at the protein level? Which class ofmutation would have an even more severe effect on theprotein?

Please explain!