Concept explainers
In tomatoes, the allele
fruit is dominant to the recessive
A
What are the genotype and phenotype of the
What are the genotypes of gametes produced by the
The
Want to see the full answer?
Check out a sample textbook solutionChapter 5 Solutions
Genetic Analysis: An Integrated Approach (3rd Edition)
- In a certain plant, leaf size is determined by fourgenes whose alleles assort independently and actadditively. Thus, alleles A, B, C, and D each add4 cm to leaf length and alleles A′, B′, C′, andD′ each add 2 cm to leaf length. Therefore,an AA BB CC DD plant has leaves 32 cm longand an A′A′ B′B′ C′C′ D′D′ plant has leaves16 cm long.a. If true-breeding plants with leaves 32 cm longare crossed to true-breeding plants with leaves16 cm long, the F1 will have leaves 24 cm longand the genotype AA′ BB′ CC′ DD′. Listall possible leaf lengths and their expectedfrequencies in the F2 generation produced fromthese F1 plants.arrow_forwardSemi-sterility in corn, as seen by unfilled ears with gaps due to abortion of approximately half the ovules, is an indication that the strain is a translocation heterozygote. The chromosomes involved in the translocation can be identified by crossing the translocation heterozygote to a strain homozygous recessive for a gene on the chromosome being tested. The ratio of phenotypic classes produced from crossing semi-sterile F1 progeny back to a homozygous recessive plant indicates whether the gene is on one of chromosomes involved in the translocation. For example, a semi-sterile strain could be crossed to a strain homozygous for the yg mutation on chromosome 9. (The mutant has yellow-green leaves instead of the wild-type green leaves.) The semi-sterile F1 progeny would then be backcrossed to the homozygous yg mutant. (a) What types of progeny (fertile or semi-sterile, green or yellow-green) would you predict from the backcross of the F1 to the homozygous yg mutant if the gene was not on…arrow_forwardA yeast geneticist irradiates haploid cells of a strain that is an adenine-requiring auxotrophic mutant, caused by mutation of the gene ade1. Millions of the irradiated cells are plated on minimal medium, and a small number of cells divide and produce prototrophic colonies. These colonies are crossed individually with a wildtype strain. Two types of results are obtained:(1) prototroph × wild type : progeny all prototrophic(2) prototroph × wild type : progeny 75% prototrophic, 25% adenine-requiring auxotrophsa. Explain the difference between these two types of results.b. Write the genotypes of the prototrophs in each case.c. What progeny phenotypes and ratios do you predict from crossing a prototroph of type 2 by the original ade1auxotroph?arrow_forward
- A PORTION OF THE LINKAGE MAP OF CHROMOSOME 2 IN THE TOMATO IS ILLUSTRATED HERE. ci (compound influorescence) o (oblate) - 15 CM 20 CM p (peach) THE OBLATE PHENOTYPE IS A FLATTENED FRUIT, THE PEACH PHENOTYPE IS HAIRY FRUIT (LIKE A PEACH), AND COMPOUND INFLORESCENCE MEANS CLUSTERED FLOWERS. IGNORE THE PEACH LOCUS. AMONG 1000 GAMETES PRODUCED BY A PLANT OF GENOTYPE O CI /+ +, WHAT TYPES OF GAMETES WOULD BE EXPECTED, AND WHAT NUMBER WOULD BE EXPECTED OF EACH?arrow_forwardDrosophila females heterozygous for 3 recessive mutations a, b, and c werecrossed to males homozygous for all 3 mutations. The cross had the followingresults:wild 75 c 348 ab 306b 96 ac 110 abc 85Based on their recombination frequencies, the map distances in cM among the 3alleles are? a-b ; b-c ; a-c?arrow_forwardRecombination frequencies between four genetically-linked loci in corn are shown in the following table: Loci Recombination Frequency (%) L and Q 20 Q and R 50 R and L 30 Q and W 13 L and W 7 What is the order of the genes on the chromosome? (note: The same answer can be represented forward or backwards. e.g. A B C D = D C B A) LQWR RQWL LRQW QRLW RLWQarrow_forward
- You are working with a hypothetical fly and have found color and wing mutants. Preliminary work indicates that the mutant traits are recessive and the associated genes are not sex-linked, but beyond that, you have no information. You first look at 2 genes, each with 2 alleles. "B" or “b" for body color and "W" or "w" for wing surface. The red-body phenotype is dominant to the yellow-body phenotype and smooth wings are dominant to crinkled wings.arrow_forwardIn an autotetraploid Chinese primrose (Primula sinensis L.), the gene controlling stigma color is very near the centromere of the chromosome carrying it. The allele G for green stigma is dominant to g for red stigmas. A homozygous green autotetraploid strain is crossed with a homozygous red autotetraploid strain. Show all solutions and label solutions and final answers properly. Derive the types of gametes the F1’s may be expected to form and the proportion of each.arrow_forwardSemisterility in corn, as seen by unfilled ears withgaps due to abortion of approximately half the ovules,is an indication that the strain is a translocation heterozygote. The chromosomes involved in the translocation can be identified by crossing the translocationheterozygote to a strain homozygous recessive for agene on the chromosome being tested. The ratio ofphenotypic classes produced from crossing semisterileF1 progeny back to a homozygous recessive plant indicates whether the gene is on one of the chromosomesinvolved in the translocation. For example, a semisterilestrain could be crossed to a strain homozygous for the yg mutation on chromosome 9. (The mutant has yellowgreen leaves instead of the wild-type green leaves.) Thesemisterile F1 progeny would then be backcrossed tothe homozygous yg mutant.a. What types of progeny (fertile or semisterile, greenor yellow-green) would you predict from the backcross of the F1 to the homozygous yg mutant if thegene was not on one of the two…arrow_forward
- In the model plant Arabidopsis thaliana, the following alleles were used in a cross: T = presence of trichomes t = absence of trichomes D = tall plants d = dwarf plants W = waxy cuticle w = nonwaxy A = presence of purple anthocyanin pigment a = absence (white) The T/t and D/d loci are linked 26 m.u. apart on chromosome 1, whereas the W/w and A/a loci are linked 8 m.u. apart on chromosome 2. A pure-breeding double-homozygous recessive trichomeless nonwaxy plant is crossed with another pure-breeding double-homozygous recessive dwarf white plant. a. What will be the appearance of the F1? b. Sketch the chromosomes 1 and 2 of the parents and the F1, showing the arrangement of the alleles.c. If the F1 is testcrossed, what proportion of the progeny will have all four recessive phenotypes?arrow_forwardThe following recombinant frequencies were found between genes A, B, C, D, and E. Determine the order of these genes on the chromosome and draw a linkage map of this chromosome with the map units labeled. А, С: 10% А, D: 30% А, Е: 6% В, С: 4% В, D: 16% В, Е: 20% C, D: 20%arrow_forwardYou are mapping three linked loci in Drosophila melanogaster (the common laboratory fruit fly). You cross flies that are triply mutant for apricot (pale eyes), bristle (extra bristles) and clipped (notched wings) to wild-type flies. The F+ flies are wild-type in appearance. You then backcross the F+ females to pure-breeding (apricot, bristle, clipped) males and score the phenotypes of 1000 F progeny for all three loci. Here are the results: 359 wild-type 361 apricot, bristle, clipped 89 bristle, clipped 91 apricot 42 apricot, bristle 38 clipped 9 apricot, clipped 11 bristle Using these data, first determine what gametes from the F; trihybrid produced each of the eight F2 categories. Note that apricot = aa (recessive to wild-type A); bristle = bb (recessive to wild-type B); and clipped = cc (recessive to wild-type C). Then determine if each gamete is recombinant (R) or nonrecombinant (R) for each pair of alleles (that is, for each genetic interval). Complete the table by dragging the…arrow_forward
- Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSONBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxAnatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
- Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & CompanyLaboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education