Concept explainers
a.
To determine: The alleles that are dominant in the given cross.
Introduction. The different forms of allele in two organisms of the species can result in changes in their appearance even though their genetic composition is highly similar. These are gene polymorphisms that accounts for the change in appearance of genetically similar organisms.
b.
To determine: The most probable genotypes for the parents in each cross.
Introduction. Recombination is the process that is exclusive to the meiotic division as it allows the exchange of genetic material between the non-homologous chromosomes. The recombination process is responsible for the shuffling of the characters and producing a zygote that is different from both the parents but have the chromosomes from both the parents.
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Introduction To Genetic Analysis
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- In some plants a red flower pigment, cyanidin, is synthesized from a colorless precursor. The addition of a hydroxyl group (OH-) to the cyanidin molecule causes it to become purple. In a cross between two randomly selected purple varieties, the following results were obtained: 94 purple 31 red 43 white How many genes are involved in the determination of these flower colors? Which genotypic combinations produce which phenotypes? Diagram the purple * purple cross.arrow_forwardIn the video game Animal Crossing: New Horizons, flowering breeding is based in genetics. Each flower's color is determined by the genotype at three or four unlinked genes: R, Y, W, and S. The genotype of the elusive blue rose is RR YY ww ss. In the game, one way to get a blue rose is to cross two roses with the Rr Yy Ww ss genotype. A) What types of gametes and in what proportions will a Rr Yy Ww ss rose produce? B) In a cross Rr Yy Ww ss x Rr Yy Ww ss what are the possible offspring genotypes and at what frequency will they each appear? Show your work. C) What proportion of the offspring of the cross will be blue roses?arrow_forwardThe production of purple pigment in a certain species of flower is dependent upon two gene loci. You cross two purple flowered plants that are heterozygous at each gene locus. The offspring show the following phenotypes: 91 purple and 68 white.a. What is the simplified phenotypic ratio is observed in the offspring? What mode of inheritance is associated with this ratio? b. What is/are the genotype(s) of the purple offspring? What is/are the genotype(s) of the white offspring?arrow_forward
- Pigment in mouse fur is only produced when the C allele is present. Individuals of the cc genotype are white. If color is present, it may be determined by the A, a alleles. AA or Aa results in agouti color, while aa results in black coats. (a) What F1 and F2 genotypic and phenotypic ratios are obtained from a cross between AACC and aacc mice? (b) In three crosses between agouti females whose genotypes were unknown and males of the aacc genotype, the following phenotypic ratios were obtained: (1) 8 agouti (2) 9 agouti (3) 4 agouti 8 white 10 black 5 black 10 white What are the genotypes of these female parents?arrow_forwardIn the pearl-millet plant, color is determined by three alleles at a single locus: Rp1 (red), Rp2 (purple), and rp (green). Red is dominant over purple and green, and purple is dominant over green (Rp1 > Rp2 > rp). Give the expected phenotypes and ratios of offspring produced by the following crosses. a. Rp1/ Rp2 × Rp1/ rp b. Rp1/ rp × Rp2/ rp c. Rp1/ Rp2 × Rp1/ Rp2 d. Rp2/ rp × rp/ rp e. rp/ rp × Rp1/ Rp2arrow_forwardA cross in Drosophila melanogaster involved the recessive X-linked genes for white eye (w), yellow body (y), and cut wings (c). A wild-type tri-hybrid female was crossed with wild-type males and only the male offspring were tallied. On the basis of the results shown below, which of the choices shown best represents the genetic map of the three loci on the X-chromosome? Phenotype Male Offspring + у t 494 394 + + ct 28 w y + 35 + у + 105 w + ct 101 w y ct 5 5.4 mu 17.6 mu ct 6.1 mu 18.3 mu w ct 17.6 mu 5.4 mu ct 18.3 mu 6.1 mu ct 6.1 mu 18.3 mu ct Submit Request Answer de Feedback Next >arrow_forward
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