Colored aleurone in the kernels of corn is due to the dominant allele R. The recessive allele r, when homozygous, produces colorless aleurone. The plant color (not kernel color) is controlled by another gene with two alleles, Y and y. The dominant Y allele results in green color, whereas the homozygous presence of the recessive y allele causes the plant to appear yellow. In a testcross between a plant of unknown genotype and
colored, green | 88 |
colored, yellow | 12 |
colorless, green | 8 |
colorless, yellow | 92 |
Explain how these results were obtained by determining the exact genotype and phenotype of the unknown plant, including the precise association of the two genes on the homologs (i.e., the arrangement).
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- You have a purple-flowered pea plant, but you do not know if it is homozygous (PP) or heterozygous (Pp) for flower color because both genotypes result in the same purple phenotype. Purple color allel (P) is dominant over white flower allel (p). What would you do to determine the genotype of flower color of this plant? Lötfen birini seçin: O a. Crossing the plant with homozygous large flowered pea plant (LL) Ob. Crossing the plant with heterozygous purple flowered pea plant (Pp) Crossing the plant with homozygous dominant purple flowered pea plant (PP) d. Crossing the plant with a plant whose genotype is unknown e. Crossing the plant with homozygous recessive white flowered pea plant (pp)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_forwardThe production of eye-color pigment in Drosophila requires the dominant allele A. The dominant allele P of a second independent gene turns the pigment to purple, but its recessive allele leaves it red. A fly producing no pigment has white eyes. Two pure lines were crossed with the following results:P red-eyed female white-eyed maleF1 purple-eyed femalesred-eyed malesF1 F1purple eyed 38red eyed 38white eyed 28F both males and females: 2Explain this mode of inheritance, and show the genotypes of the parents, the F1, and the F2.arrow_forward
- Summer squash color is determined by the interaction of more than one gene. The presence of CC or Cc allele combinations produces a squash that is white in color, and the C allele is epistatic to the G allele. The presence of GG or Gg produces a squash that is yellow in color, and ccgg produces a squash that is green. After two fully heterozygous squash are crossed. Give the phenotypes, and frequency of occurrence, of the F2 offspringarrow_forwardDominant allele R in corn results in purple kernel, while recessive allele r results in pearl white kernel in homozygous condition. The plant body colour is controlled by another gene with two alternative alleles, G for green colour and g for yellow colour. In a testcross between a corn plant with unknown genotype and a plant that is homozygous recessive for both genes, the following progeny were obtained: Phenotype Purple, green Purple, yellow Pearl white, green Pearl white, yellow Number 90 12 10 88 Explain how these results were obtained by determining the exact genotype of the unknown plant. Include the precise gene arrangement on the homologous chromosomes.arrow_forwardIn Bean plants two genes are defined below with the lower case letter indicating the recessive allele. yellow flower color a = green flower color. B = spotted pods b = plain pods A = A parental generation cross is made between a pure breeding plant with yellow flower color and spotted pods, to a pure breeding plant with green flower color and plain pods. Write this parental generation cross using the symbols defined above. Write the genotype of the F1 plants. An F1 plant is then testcrossed. Write this testcross using the symbols defined above.arrow_forward
- In com, colored aleurone (in the kernels) is due to the dominant allele R. The recessive allele r, when homozygous, produces colorless aleurone. The plant color (not the kernel color) is controlled by another gene with two alleles Y and y. The dominant Y allele results in green color, whereas the homozygous presence of the recessive y allele causes the plant to appear yellow. In a testcross between a plant of unknown genotype and phenotype and a plant that is homozygous recessive for both traits, the following progeny were obtained. Numbers of Offspring Phenotype Colored Aleurone & Green Plant 88 Colored Aleurone & Yellow Plant 12 Colorless Aleurone & Green Plant 8 Colorless Aleurone & Yellow Plant 92 Question: Determine the genotype and phenotype of the unknown plant, including the precise association of the two genes on the homologs (i.e. the map arrangement)arrow_forwardIn a species of roses, the alleles RP and RR code for pink roses and red roses, respectively. In this case, the wild-type phenotype is red roses in which the locus exhibits a paramutation. The presence of RP with RR leads to a paramutation of RR to RP", which results in pink roses. This paramutation is 100% penetrant. If a heterozygous rose is crossed with a homozygous red rose, what is the phenotypic ratio of the offspring? O % pink and % red none pink and all red O all pink and none red O % pink and redarrow_forwardSometimes, two alleles are neither dominant nor recessive, therefore, both alleles are expressed separately in a heterozygous individual. This is called codominance. Which of the following is an example of codominance? a In guinea pigs, black hair is dominant over white hair. A homozygous black guinea pig is crossed with a homozygous white guinea pig. The first generation of offspring are black. b If you cross a plant with blue flowers with a plant with yellow flowers, the offspring will have blue flowers with yellow spots. c If you cross a rhododendron plant with red flowers with a rhododendron plant with white flowers, the offspring will have pink flowers. d A white female cat mates with a brown male cat. The resulting offspring are orange.arrow_forward
- A is dominant over a and B is dominant over b. Genes A/a and B/b assort independently. The parental cross (P) is between true- breeding (homozygous) strains (AA bb x aa BB). The resulting F1 offspring would be [Select ] A F1 x F1 cross gives the F2 generation. The ratio of phenotypes in the F2 generation can be described as [ Select ] In the phenotypic ratio, what number refers to individuals that are: dominant for both traits? [ Select ] recessive for both traits? [Select ] To what phenotypes do the "3"s in the ratio refer? [ Select ] > >arrow_forwardThe fur color gene in rabbits has a dominant allele B with a black phenotype and a recessive allele with a brown phenotype. The rabbit hair length gene has a dominant allele S for short hair, and a long hair recessive allele s. In a cross between a homozygous black-long-hair rabbit with a homozygous brown-short rabbit, what would be the genotype(s) B_s_ v and phenotype(s) [ Select ] of the F1 generation? What would be the genotype(s) [ Select ] and phenotype(s) [ Select ] of the F2 generation?arrow_forwardIn roses, purple flower color is determined by the dominant P allele, while pp homozygotes are white. The presence of long stems is determined by the dominant S allele, while ss homozygotes have short stems. Both mutations are completely penetrant. A test cross was performed between a rose plant of unknown genotype with a white flowered, short stemmed rose plant (pp ss) and the following 200 progeny plants were obtained: 84 white flowers, long stems 16 purple flowers, long stems 82 purple flowers, short stems 18 white flowers, short stems Select the statements below that are TRUE. Select 2 correct answer(s) The P and S genes independently assort during meiosis. The map distance between P and S is 17 CM. The genotype of the progeny plants with purple flowers and short stems is PP ss. The map distance between P and S is 83 CM. The homologs in the plant with unknown genotype are p S and Ps. The homologs in the plant with unknown genotype are PS and p s.arrow_forward
- Concepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax College