Concept explainers
In the tomato, three genes are linked on the same chromosome. Tall is dominant to dwarf, skin that is smooth is dominant to skin that is peachy, and fruit with a normal rounded tomato shape is dominant to oblate (flattened) shape. A plant that is true-breeding for the dominant traits was crossed to a dwarf plant with peachy skin and oblate fruit. The
151 tall, smooth, normal
33 tall, smooth, oblate
11 tall, peach, oblate
2 tall, peach, normal
155 dwarf, peach, oblate
29 dwarf, peach, normal
12 dwarf, smooth, normal
0 dwarf, smooth, oblate
Construct a genetic map that shows the order of these three genes and the distances between them.
Trending nowThis is a popular solution!
Chapter 6 Solutions
Genetics: Analysis and Principles
- Individuals of genotype AaBb were mated to individuals of genotype aabb. One thousand offspring were counted, with the following results: 474 Aabb, 480 aaBb, 20 AaBb, and 26 aabb. What type of cross is it? Are these loci linked? What are the two parental classes and the two recombinant classes of offspring? What is the percentage of recombination between these two loci? How many map units apart are they?arrow_forwardIn a variety of tomato plant ,the leaves maybe pure green,pure white,or variegated (mixture). a)when 2 variegated plants were crossed,87 offspring were produced,of these 20 were green,46 were variegated and 21 remain died soon after germination.Draw a genetic diagram to explain these results,why did 21 of them diedarrow_forwardA variety of opium poppy (Papaver somniferum L.) with lacerate leaves was crossed with a variety that has normal leaves. All the F1 had lacerate leaves. Two F1 plants were interbred to produce the F2. Of the F2, 249 had lacerate leaves and 16 had normal leaves. Give genotypes for all the plants in the P, F1, and F2 generations. Explain how lacerate leaves are determined in the opium poppy.arrow_forward
- A snapdragon plant that bred true for white petals was crossed to a plant that bred true for purple petals and all the F1 have white petals. The F1 was selfed. Among the F2 three phenotypes were observed in the following numbers: White--> 240 Solid Purple --> 61 Spotted Purple --> 19 a) Propose the correct genetic explanation for this phenomenon. Define your genetic symbols and show the genotypes of the Parentals, F1, and F2 individuals above. You may use underscores ( _ ) where appropriate. Please clearly label your answer. b) Complete a chi square to defend your answer. Be sure to include chi, Ho and Ha. Do not forget to interpret your test.arrow_forwardIn the tomato plant, red fruit (R) is dominant over green (r). Smooth fruit skin (S) is dominant over peachy skin (s). The genes for fruit colour and fruit texture are linked on the same chromosome. A heterozygous red, heterozygous smooth plant was crossed with a green, peachy plant. The results are given:Smooth-red = 28Smooth-green 567Peachy-red = 534Peachy-green = 34i. Calculate the map distance between the genes.ii. The map distance calculated in (i) is not representing the true distance between the genes? Provide your argument.arrow_forwardIn the garden pea, orange pods (p) are recessive to green pods (P), and sensitivity to pea mosaic virus (mo) is recessive to resistance to the virus (Mo). A plant with orange pods and sensitivity to the virus was crossed to a true-breeding plant with green pods and resistance to the virus. The F1plants were then testcrossed to plants with orange pods and sensitivity to the virus. The following results were obtained:160 orange pods, virus-sensitive; 165 green pods, virus-resistant;36 orange pods, virus-resistant; 39 green pods, virus-sensitive Question: Conduct a chi square analysis to see if these genes are linked.arrow_forward
- In watermelons, bitter fruit (B) is dominant over sweet fruit (b), and yellow spots (S) are dominant over no spots (s). The genes for these two characteristics assort independently. A homozygous plant that has bitter fruit and yellow spots is crossed with a homozygous plant that has sweet fruit and no spots. The F1 are intercrossed to produce the F2. What will be the phenotypic ratios in the F2? 2. If an F1 plant is backcrossed with the bitter, yellow-spotted parent, what phenotypes and proportions are expected in the offspring? 3. If an F1 plant is backcrossed with the sweet, non-spotted parent, what phenotypes and proportions are expected in the offspring? 4. In cats, curled ears (Cu) result from an allele that is dominant over an allele for normal ears (cu). Black color results from an independently assorting allele (G) that is dominant over an allele for gray (g). A gray cat homozygous for curled ears is mated with a homozygous black cat with normal ears. All the F1…arrow_forwardYou are studying three linked genes in snapdragons. The flower color locus is in the center. There are 8.3 cM between the flower color locus and the plant height locus. There are 12.4 cM between the flower color locus and the leaf type locus. The coefficient of coincidence is 0.8. Pure-breeding tall, red-flowered plants with fuzzy leaves were crossed to pure-breeding dwarf, blue-flowered plants with smooth leaves. The F1 were testcrossed. Calculate the proportion of the testcross progeny that are expected to have red flowers and fuzzy leaves. Round properly to 4 decimal digits. Answer:arrow_forwardTwo pure-breeding lines of petunia plants are crossed. Line 1 plants grow to a height of 54 cm, and Line 2 plants grow to a height of 18 cm. Petunia plant height is controlled by three genes, A, B and C. Line 1 has the genotype A₁A₁B₁B₁C₁C₁, and line 2 has the genotype A2A2B₂B₂C₂C₂. Assume that genotype alone determines plant height under ideal growth conditions and that the alleles of the three genes are additive. If the F1 plants are self crossed, what is the expected proportion of F2 plants with the genotype A₁A₁B₁B₁C₁C₁ 1/8 1/32 1/16 1/4 1/64arrow_forward
- In tomatoes, a heterozygous plant with normal fruit and purple stems is crossed with a recessive plant having fasciated fruit and green stems (test cross). The following distribution of offspring is observed: normal fruit, purple stems 38.5% fasciated fruit, green stems 38.5% normal fruit, green stems 11.5% fasciated fruit, purple stems 11.5% What is the recombination frequency?arrow_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_forwardIn corn plants, a dominant allele (K) allows kernel colour and a recessive allele (k) inhibits kernel colour when homozygous. On a different chromosome, the dominant gene P causes purple kernel colour and the homozygous recessive genotype causes red kernel colour.A true breeding white corn plant was crossed with a purple corn plant, yielding 50% red corn plants and 50% purple corn plants.What are the genotypes of the parental corn plants? Select one: a. KKPp kkpp b. KkPP kkPP c. kkPp KkPp d. KKPP kkPparrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage LearningBiology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning