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Flower color in snapdragons results from the amount of the pigment anthocyanin in the petals. Red flowers are produced by plants that have full anthocyanin production, and ivory-colored flowers are produced by plants that lack the ability to produce anthocyanin. The allele
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Genetic Analysis: An Integrated Approach Plus Mastering Genetics with Pearson eText -- Access Card Package (3rd Edition) (What's New in Genetics)
- 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_forwardDiscuss why Mendel's hybrid offspring begin to exhibit the original traits expressed by the P1 generation or the pure-breeding parents used in the original cross. What would happen if the hybrid offspring were allowed to breed without interference from Mendel for an extended period of time and the different ways plants can breed.arrow_forwardThe results of a test cross of a plant that is heterozygous for three traits encoded by the genes D, R, and Q are summarized in the table (below), which shows the numbers of offspring that inherited each combination of alleles from the heterozygous parent. Use the data collected to make a genetic map of genes D, R, and Q. Make a map of the distance between these three genes. Report your results by entering the genetic distance between each pair of genes to the nearest 0.1 cM in the blanks below. Distance D-Q: Distance D-R: Distance Q-R: Alleles from heterozygous parent R d d D D D D d r R r r R r R Number q 474 Q 289 q 286 q 30 Q 475 Q 155 159 32 q Q cM см cMarrow_forward
- The shape of a pumpkin is determined by the action of two genes A and B. The recessive forms of these two alleles produces a flattened-shaped fruit, whereas the dominant forms of these two alleles produce the typical pumpkin with ridges. When both alleles are heterozygous a disc-shaped pumpkin is produced. If the genotype of the pumpkin plant is homozygous dominant at one allele and heterozygous at the other, the pumpkin will be ball-shaped. If the pumpkin plant is homozygous recessive at one allele and heterozygous at the other allele it produces an oblong-shaped fruit. Plants with genotypes other than the ones listed in this question do not produce pumpkins. Do the following cross: two pumpkin plants capable of making disc-shaped pumpkins are crossed with each other. Based on this cross, answer the following: (Show your work below.) How many of the progeny will make ball-shaped pumpkins?__________________________________________ How many of the progeny will make disc-shaped…arrow_forwardA horticulturist runs a test cross with an offspring (F1 generation) purple plant from Question 8. The phenotypic frequencies of the resulting offspring are 50% white and 50% purple. What is the true genotype of this offspring (F1 generation) purple plant?arrow_forwardUse the following information to answer the next question. A Venn Diagram Showing the Relationship Between Oogenesis and Spermatogeneis. Oogenesis 1 NOTE: Similarities are represented by area 2. Differences are represented by areas 1 or 3. Match the numbered regions with the descriptions below. Spermatogenesis 3 Four viable gametes produced: Occurs in gonads: Daughter cells equal in size Unequal cytoplasmic division ▶arrow_forward
- Waxy endosperm (wx), shrunken endosperm (sh) and yellow seedling (v) are encoded by three recessive genes in corn that are linked on chromosome 5. A corn plant homozygous for all three recessive alleles is crossed with a plant homozygous for all the dominant alleles. The resulting F1 are then crossed with a plant homozygous for the recessive alleles in a three point test cross. The progeny of the test cross are: wx sh WX SH V WX SH V Wx sh WX sh V SH v SH V V 87 1,515 94 WX 1,531 3,479 292 WX Wx sh v 3,478 280 a. Determine the order of the genes on the chromosome. b. Calculate the map distances between the genes. c. Determine the cc and I.arrow_forwardIn garden pea plants, tall stem height (T) is dominant over short stem height (t), and green pod colour (G) is dominant over yellow pod colour (g). Some Genotypes of Pea Plants TTGG TTGg TTgg TtGG TtGg Ttgg ttGG ttGg ttgg Identify the correct genotypes listed above for the pea plant phenotypes described below. Phenotype Number Pure breeding tall, green pod pea plant Answer Pea plant used for a test cross Answer Heterozygous tall and green pod pea plant Answer Yellow pod heterozygous tall pea plant Answerarrow_forwardIn this program, you are provided with phenotype pair counts of F2 offspring at two research institutes. The key different between this work and previous work is that now we consider two genes instead of one. The phenotype pairs are the (shape, color) of peas from a pea plant. It turns out that there are two separate genes that code for these phenotypes. We shall call them Shape and Color. Gregor Mendel originally recorded these experiments in green peas. Using the notation: R = Round (dominant) allele at Shape gene; r = Wrinkled (recessive) allele at Shape gene; Y = Yellow (dominant) allele at Color gene; y = Green (recessive) allele at Color gene; then the shape and color of any pea can be determined by studying the genotypes at each gene. It turns out that, when one mates a plant that is homozygous for the dominant alleles (RRYY) with a plant that is homozygous for the recessive alleles (rryy), the F1 generation are heterozygous at both genes, as with a single gene disorder.…arrow_forward
- A type of flower called the Rhododendron has a CW allele that leads to red flower color and a CW allele that leads to white flower color. Rhododendrons with the heterozygous genotype CWCW have flowers with red and white patches. Another gene controls leaf shape, with the dominant allele R leading to oval leaves and the recessive allele r leading to rounded, shorter leaves. If you cross two Rhododendrons that are heterozygous for flower color and leaf shape: a) What ratio/fraction of offspring would you expect to have red flowers and oval leaves? b) What ratio/fraction of offspring would you expect to have white flowers and rounded leaves? c) What ratio/fraction of offspring would you expect to have red-and-white flowers and oval leaves?arrow_forwardIn some plants a red pigment is synthesized from a colorless precursor. The addition of a hydroxyl group to the precursor molecule causes it to become purple. In a cross between two randomly selected purple plants, the following results were obtained. 94 purple 31 red 43 white Q:What are the genotypes of the two random purple plants? R/r; P/p X R/r; P/p R/r; p/p X R/r; p/p r/r; P/p X r/r; P/p r/r; p/p X r/r; p/p R/R; P/P X r/r; p/parrow_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_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage LearningConcepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax College