ExamsFall 20007.03 Exam 1Name:Section: TA:Exam starts at 11:05 and ends at 11:55There are seven pages including this cover pagePlease write your name on each page.Also...• Look over the entire exam soyou don't spend too much time onhard questions leaving easy questions unanswered.• Check your answers to makesure that they make sense.• To help usgive partial credit, showyour work andstate any assumptions that you make.Question I 35 pointsQuestion 2 35 pointsQuestion 3 30 pointsName:1. (a 4 pts.) Wild type yeast form white colonies. You have isolated twomutants that make red colonies that you call red1- and red2-. When a redl-mutant is mated to a red2- mutant of the opposite mating type the resultingdiploid makes white colonies. What does this observation tell us about redl-and red2-?(b 9 pts.) When the diploids from part (a) are sporulated, three types of tetradsare found.Type I have 4 red coloniesType II have 1 white and 3 red coloniesType III have 2 white and 2 red coloniesClassify each tetrad type as PD, NPD or T.Type I TypeII TypeIII(c 10 pts.) When the number of each tetrad type is tallied you find that the crossproduces 30 Type I tetrads, 16 Type II tetrads, and 4 Type III tetrads.Are the red1- and red2- mutations linked? If so, how far apart are they in cM?Name:(d 12 pts.) One of the Type IItetrads from above is selected for further analysisand you designate the four spore clones a, b, c, and d. Clone a is white,whereas clones b, c, and d are red. Each clone is mated to either a redl-mutant or a red2- mutant and the color of the resulting diploid is noted.j x red1- --->white diploidClone a (white)x red2- -->white diploidx red1- --> red diploidClone b (red)x red2- --> white diploidx red1- --> red diploidClone c (red)x red2- --> red diploidx red1- --> white diploidClone d (red)x red2- _ red diploidGive the genotypes of each of the four spore clonesClone a:Clone b:Clone c:Clone d:Name."2. Consider the following pedigree where two first cousins have a son.Each individual is numbered for reference in this problem.4(a 15 pts.) Say that female 1 is affected by a rare recessive X-linked trait and thatmale 2 does not have the trait. Assume that individuals 3 and 6 neither have norare carriers of the trait.What is the probability that male 4 will be affected by the trait?What is the probability that female 5 will be affected by the trait?What is the probability that female 7 will be affected by the trait?What is the probability that male 8 will be affected by the trait?What is the probability that male 9 will be affected by the trait?Name:(b 20 pts.) Now say that female 1 is affected by two different rare recessiveX-linked traits that are 10 cM apart (wewill refer to them as trait 1 and trait 2).Male 2 does not exhibit eithertrait. Assume that individuals 3 and 6 neither havenor are carriers of either trait.What is the probability that male 4 will be affected by both trait 1 and trait 2?What is the probability that male 8 will be affected by both trait 1 and trait 2?What is the probability that male 9 will be affected by trait 1 only?What is the probability that male 9 will be affected by both trait 1 and trait 2?What is the probability that male 9 will be affected by neither trait 1 nor trait 2?Name:3. Consider two recessive Drosophila mutants that are on the same autosome:curly-wings (cr) and humpback (hb-1). A wild type female is crossed to acurly-winged, humpbacked male to produce F1flies that all look normal. An F1female is then crossed to a curly-winged humpbacked male and 100 progenyfrom this cross are examined.Phenotype Numberwildtype 43curly-wings 11humpback 9curly-wings, humpback 37(a 10 pts.) What is the distance between the cr and the hb-1 mutations in cM?Next you isolate a second recessive humpback mutation (hb-2). A female from atrue breeding hb-2 strain is crossed to a male from a true breeding cr, hb-1strain. An F1female from this cross is then crossed to a male from a truebreeding cr, hb-1 strain and 500 progeny are examined.Phenotype Numbercurly-wings 5humpback 240curly-wings, humpback 255(b 10 pts.) What is the distance between the hb-1 and hb-2 mutations in cM?Name:(c 10 pts.) Draw a genetic map showing the relative order of the cr, hb-1, andhb-2 mutations as well as the distances that you have determined.7.03 Exam 1Section: TA:Exam starts at 11:05 and ends at 11:55There are seven pages including this cover pagePlease write your name on each page.Also...• Look over the entire exam so you don't spend too much time onhard questions leaving easy questions unanswered.• Check your answer's to make sure that they make sense.• To help us give partial credit, show your work and -state any assumptions that you make,Question 1 35pointsQuestion 2 35 pointsQuestion 3 30pointsName:?.1,t,t(a4pts.) Wild type yeast form white colonies. -Youhave isolated twomutants that make red colonies that you call red1- and red2-, When a redl-mutant is mated to a red2- mutant of the oppos'ite mating type the _,esultingdiploid makes white colonies. W.hatdoes this observation tell us about redl-and red2-?(b 9 pts.) When the diploids from part (a) are sporuiated, three types of tetradsare found.Type I have 4 red colonies -Type tl have 1 white and 3 red coloniesType l]J have 2 white and 2 red coloniesClassify each tetrad type as PD, NPD or T.Tvoel _TypeIt TvoeIII(c 10 pts.) When the number of each tetrad type is tallied you find that the cross -Aproduces 30 Type I tetrads, 16 Type 11tetrads, and 4 Type III tetrads.Are the red1- and red2- mutations iinked? If so, howfar apart are they in cM?\ "\Name:(d 12 pts.) One of the Type II tetrads from above is selected for fu_her analysisand you designate the four spore clones a, b, c, and d. Clone a is white,whereas clones b, c, and d are red. Each clone is mated to either _ redl-mutant or a red2- mutant and the color of the "esulting diploid is noted... j x red1- --+ white diploidClone a (white)x red2- --> white diploidx red1- --+ red diploidClone b (red)x red2- --> white diploidx red1- --+ red diploidClone c (red)x red2- --> red diploidx red1- -+ white diploidClone d (red)"_ x red2- _ red diploidGive the genotypes of each of the four spore clones,_s- 3r-aone : [£0"_.I._.Lt09. ..Clone b: f-£c.[ \ - t_£% _'rClone c: C@c:_\ - "C-_c[ 7---Cloned: 4-Name:2./• _ Consider the following _edigree where two first cousins have a son.,_..Each individual is numbered for reference in this problem.(a 15 pts.) Say that female 1 is affected by a rare
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