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You have already localized the genes to the same chromosome by deletion mapping, and now decide that the best way to accomplish the mapping is to conduct two simultaneous three-point testcross experiments. The genes you are investigating are as follows: N = round leaves, n = notched leaves; H = smooth stems, h = hairy stems; R = purple flowers, r = red flowers; B = grey seeds, b = black seeds; and Y = green pods, y = yellow pods. Earlier experiments you have done already established that gene B is in the middle of this gene cluster, so you design both three-point test crosses to include that gene. Cross #1 is designed as RrHhBb x rrhhbb while cross #2 is NnBbYy x nnbbyy. The results of both crosses are given in the table below.
Based on the information given, determine the arrangement of these five genes including the position of each allele in the heterozygous fly and the distances between each pair of genes. (Hint: treat each experiment separately, knowing that gene B is in the middle!)
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- 41) A pea plant known to be heterozygous at three loci is test crossed. The progeny phenotypes and the frequencies are as follows: abç +++ abc +bc a++ ++c ab+ +b+ a+c 455 470 35 33 37 -- 35 460 475 bac +++ What is the linkage arrangement of the genes? a) abc b) bac c) acb e) ab are linked c assorts independently d) ac are linked b assorts independentlyarrow_forwardRound (R) seed shape is dominant to wrinkled (r) seed shape in pea plants. If an RR plant is crossed with an rr plant, what is the frequency of phenotypes in the F2 generation? 1)1/4 RR, 1/2 Rr, 1/4 rr 2) All round seeds 3) 3 roundseeds, 1 wrinkled seed 4) All wrinkled seedsarrow_forwardConsider the first category of test-cross offspring shown in figure 8.2 (+b, LS). Consider also that the parents of the heterozygous female flies in the test cross had the following genotypes: bb, SS, and +, LL. A. What would be the physical phenotype of these flies? B. If PC was conducted with the DNA of one of these flies using the primers for the molecular marker, what would be the appearance of the bands on an electrophoresis gel with the PC products? C. If the gene for black body and the locus for the molecular marker (L long or S short) were unlinked, what proportion of the test-cross progeny would be black flies that are heterozygous for the molecular marker? What proportion would be flies with normal body color, which are homozygous for one form of the molecular marker? D. If the gene for black body and the locus for the molecular marker were linked, how would the proportion of flies be different?arrow_forward
- Please , if you don’t know the answer just don’t solve it , I don’t want from google or from websites .arrow_forwardYou perform a cross between two plants, one MmPp and one mmpp, and obtain offspring with the following phenotypes: 42 MP; 374 Mp; 367 mP; 27 mp. What can you conclude from these data? Group of answer choices The M and P genes are on different chromosomes The recombinant progeny are mP and Mp The M and P genes are far apart on the same chromosome The recombinant progeny are MP and mparrow_forwardA pea plant with the genotype RrYYPpIiaa is crossed with a second pea plant with genotype RRyyPPiiAa where round seeds (R) are dominant to wrinkled (r), yellow seeds (Y) are dominant to green (y), purple petals (P) are dominant to white (p), inflated pods (I) are dominant to pinked (i), and axial flowers (A) are dominant to terminal (a). What is the probability that these two parental pea plants will produce an offspring with the following genotype RrYyPPiiaa?arrow_forward
- Waxy endosperm (wx), virescent seedling (v), and shrunken endosperm (sh) are all recessive mutants in corn. Waxy and shrunken are both on chromosome IX, located 18 map units apart. Virescent is on chromosome V and is not linked to the other loci. A strain of corn that is homozygous for waxy and virescent is crossed to a strain that is homozygous for shrunken endosperm. The F1 were entirely wild type. An F1 individual was then test crossed to a strain that is homozygous for waxy, virescent, and shrunken. Of 1,000 offspring, how many of the offspring will be virescent and shrunken, but not waxy? Using the information from Problem 1, how many of the offspring will be waxy, virescent, and shrunken?arrow_forwardPlease explain how I can solve this. Thank you You wanted to draw a linkage map for three genes in the fruit fly (A, B, C) that you suspect are linked. You have done a three-point testcross and found that out of the 1500 progeny in the cross, 612 are a · b · c, 603 are A · B · C, 93 are a · B · C, 85 are A · b · c, 53 are a · b · C, 47 are A · B · c, 5 are A · b · C, and 2 are a · B · c. From this data, you can deduce that the genes are linked and the distance between B and C is:arrow_forwardHello, can someone pls explain this to me. I am very confused. Please be clear and i will make sure we are both satisfiedarrow_forward
- L, R, P and D are four genes located on the same chromosome in a diploid organism. Map distances between different pairs of genes were determined and the following results obtained. Based on these data, what is the order of the genes on the chromosome? D-R: 35 CM P-D: 5 CM L-R: 10 CM D-P: 30 CM D-L 25 CM P-R: 40 CM Note that only one orientation of the order is given as an answer choice. For example: ABCD has the same order as DCBA, but only ABCD would be listed as a possible answer. So be sure to check both orientations when comparing your gene order to the possible answer choices. D-L-P-R P-D-L-R P-R-D-L L-P-R-D R-L-D-Parrow_forwardIn corn, a colored aleurone is due to the presence of an R allele; r/r is colorless. Another gene controls the color of the plant, with g/g being yellow and G_being green. A plant of unknown genotype is test-crossed, and the following progeny plants were obtained. Colored green 89 Colored yellow 13 Colorless green 9 Colorless yellow 92 What is the recombination frequency between the R locus and the G locus? A. 45.6% B. 9.85% C. 91.15% D. 4.93% E. 6.4%arrow_forwardYou cross a true-breeding yellow-bodied, smooth-winged female fly with a true-breeding red-bodied, crinkle-winged male. The red body phenotype is dominant to the yellow body phenotype and smooth wings are dominant to crinkled wings. Use B or b for body color alleles, and W or w for wing surface alleles.(4 points) a) What are the genotypes of the P generation flies? b) What will be the genotype(s) and phenotype(s) of the F1 offspring? c) You discover that the genes for body color and wing surface are linked. You perform a dihybrid test cross between the F1 flies from part (b) with a true-breeding yellow-bodied, crinkle-winged fly. Use the following results of this cross to determine the recombination frequency (%) between the body color and wing surface genes. (Remember that the recombinants are the ones that do not resemble the parental types from the P generation.) Body Color Wing Surface # of Individuals red smooth 102 yellow smooth 404 red crinkled 396 yellow crinkled…arrow_forward
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