Genetics: Analysis and Principles
6th Edition
ISBN: 9781259616020
Author: Robert J. Brooker Professor Dr.
Publisher: McGraw-Hill Education
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Chapter 28, Problem 16CONQ
Many beautiful varieties of roses have been produced, particularly in the last few decades. These newer varieties often have very striking and showy flowers, making them desirable as horticultural specimens. However, breeders and novices alike have noticed that some of these newer varieties are not very fragrant compared with the older, more traditional varieties. From a genetic point of view, suggest an explanation why some of these newer varieties with superb flowers are not as fragrant.
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Chapter 28 Solutions
Genetics: Analysis and Principles
Ch. 28.1 - 1. Which of the following is an example of a...Ch. 28.1 - 2. Saying that a quantitative trait follows a...Ch. 28.2 - The variance is a. a measure of the variation...Ch. 28.2 - 2. Which of the following statistics is used to...Ch. 28.3 - 1. For many quantitative traits, genotypes and...Ch. 28.4 - A QTL is a __________ where one or more genes...Ch. 28.4 - 2. To map QTLs, strains are crossed that differ...Ch. 28.5 - 1. In a population of squirrels in North Carolina,...Ch. 28.5 - Prob. 2COMQCh. 28.5 - 3. One way to estimate narrow-sense heritability...
Ch. 28.6 - 1. For selective breeding to be successful, the...Ch. 28.6 - Prob. 2COMQCh. 28 - Give several examples of quantitative traits.How...Ch. 28 - 2. At the molecular level, explain why...Ch. 28 - 3. What is a normal distribution? Discuss this...Ch. 28 - 4. Explain the difference between a continuous...Ch. 28 - What is a frequency distribution? Explain how such...Ch. 28 - 6. The variance for weight in a particular herd of...Ch. 28 - Two different varieties of potato plants produce...Ch. 28 - 8. If , would you conclude that a positive...Ch. 28 - Prob. 9CONQCh. 28 - When a correlation coefficient is statistically...Ch. 28 - 11. What is polygenic inheritance? Discuss the...Ch. 28 - What is a quantitative trait locus (QTL)? Does a...Ch. 28 - 13. Let’s suppose that weight in a species of...Ch. 28 - Prob. 14CONQCh. 28 - 15. From an agricultural point of view, discuss...Ch. 28 - Many beautiful varieties of roses have been...Ch. 28 - 17. In your own words, explain the meaning of the...Ch. 28 - 18. What is the difference between broad-sense...Ch. 28 - The heritability for egg weight in a group of...Ch. 28 - In a fairly large population of people living in a...Ch. 28 - When artificial selection is practiced over many...Ch. 28 - 22. Discuss whether a natural population of wolves...Ch. 28 - 23. With regard to heterosis, is each of...Ch. 28 - Here are data for height and weight among 10 male...Ch. 28 - 2. The abdomen length (in millimeters) was...Ch. 28 - 3. You conduct an RFLP analysis of head weight in...Ch. 28 - 5. Let’s suppose that two strains of pigs differ...Ch. 28 - Prob. 6EQCh. 28 - In a wild strain of tomato plants, the phenotypic...Ch. 28 - The average thorax length in aDrosophilapopulation...Ch. 28 - 9. In a strain of mice, the average 6-week body...Ch. 28 - Prob. 10EQCh. 28 - 11. A danger in computing heritability values from...Ch. 28 - For each of the following relationships,...Ch. 28 - An animal breeder had a herd of sheep with a mean...Ch. 28 - The trait of blood pressure in humans has a...Ch. 28 - Discuss why heritability is an important...Ch. 28 - From a biological viewpoint, speculate as to why...Ch. 28 - 3. What is heterosis? Discuss whether it is caused...
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- Sunflowers with flowers 10 cm in diameter are crossed with a plant that has 20-cm flowers. The F1 plants have flowers 15 cm in diameter. In the F2 generation, 4 flowers are 10 cm in diameter and 4 are 20 cm in diameter. Between these are 5 phenotypic classes with diameters intermediate to those at the extremes. a. Assuming that the alleles that contribute to flower diameter act additively, how many genes control flower size in this strain of sunflowers? b. How much does each additive allele contribute to flower diameter? c. What size flower makes up the largest phenotypic class?arrow_forwardIn a genetic cross between a homozygous tall plant with homozygous purple flowers and a homozygous short plant with heterozygous purple flowers, how many short plants will you expect in the F2 generation if you sample 36 individuals? Both tall and purple are dominant.arrow_forwardA type of fast plant strain that can be used to study genetics is yellow green leaf in which the homozygous recessive plant will have pale yellow-green leaves. Predict the F1 generation phenotype of a cross between a dwarf rosette plant and a pale yellow green plant. short and green short and yellow-green tall and yellow-green tall and greenarrow_forward
- The best way to determine the genotype for a plant presenting with dominant phenotypes is by performing a test cross. Test crosses are always performed with a true-breeding plant with recessive traits. What would be the phenotype and genotype of the plant you would need to perform the test-cross with your tall, purple plant?After performing the test-cross with your unknown purple, tall plant you find that all your resulting plants are tall; half have white flowers, and half have purple flowers. What was the genotype of your original purple, tall plant?arrow_forwardTwo true breeding plants are cross pollinated. One plant is homozygous dominant for heightand color while the other is homozygous recessive for height and color. (A:tall, a:short, B:brown,b:red) The F1 plants are allowed to self-fertilize to produce an F2 generation. After conductingan experiment we get the following results:398 tall and brown plants122 tall and red plants128 short and brown plants45 short and red plants Using the Chi Square formula and table, determine if your results support the hypothesis ofindependent assortment or not. Show your work. You don’t need to show your Punnett Squaresif you include a statement as to how you figured out the appropriate phenotypic ratio for the F2generation. Round to 1 decimal.4a. What possible gametes can the following individual make: AaBb4b. What possible gametes can the following individual make: AaBbCCarrow_forwardThe trait for medium-sized leaves in iris is determined by the genetic condition PP'. Plants with large leaves are PP, whereas plants with small leaves are P'P'. The trait for red flowers is controlled by the genes RR, pink by RR', and white by R'R'. A cross is made between two plants each with medium-sized leaves and pink flowers. If they produce 640 seedlings, what would be the expected phenotypes, and in what numbers would they be expected? View keyboard shortcuts EditViewInsertFormatToolsTable 12pt Paragrapharrow_forward
- ) Radish flowers may be red, purple, or white. A cross between a red-flowered plant and a white-flowered plant yields all-purple offspring. The part of the radish we eat may be oval or long, with long being the dominant trait. If true-breeding red-flowered long radishes are crossed with true-breeding white-flowered oval radishes, what would the F1 generations genotype and phenotype be For full credit, you must show all work.arrow_forwardThe trait for medium-sized leaves in iris is determined by the genetic condition PP'. Plants with large leaves are PP, whereas plants with small leaves are P'P'. The trait for red flowers is controlled by the genes RR, pink by RR', and white by R'R'. A cross is made between two plants each with medium-sized leaves and pink flowers. If they produce 640 seedlings, what would be the expected phenotypes, and in what numbers would they be expected?arrow_forwardIn tomatoes, red fruit is dominant over yellow, two-loculed fruit is dominant over many-loculed fruit, and tallvine is dominant over dwarf. A breeder has two purelines: (1) red, two-loculed, dwarf and (2) yellow, manyloculed, tall. From these two lines, he wants to produce anew pure line for trade that is yellow, two-loculed, andtall. How exactly should he go about doing so? Show notonly which crosses to make, but also how many progenyshould be sampled in each case.arrow_forward
- You self-fertilize an F1 plant to produce the F2 generation. Based on Mendelian principles of inheritance, what fraction of the F2 generation do you expect to be short with round, green seeds? HINT: Solving this problem will require a very large Punnett square (8 x 8), but you can easily solve it using the Multiplication Rulearrow_forwardA horticulturist has a purple plant and a white plant. The horticulturist knows that purple is dominant over white. When they are bred, all of the resulting offspring are purple. What is the most likely genotype of the parent or original purple plant?arrow_forwardMendel obtained his initial pea plant varieties from local breeders who were developing new varieties that might be useful or interesting. To generate these new varieties, breeders formed hybrids between existing varieties of different phenotypic characteristics by cross pollination, using techniques they doubtless taught to Mendel. After producing a hybrid, they allowed several generations of self-pollination, as happens naturally if the flowers are not disturbed. a. What if a breeder were working with 7 different, independently segregating genes, as Mendel did? How many generations would it take him to have pure-breeding varieties, starting from an F1 hybrid that is heterozygous for all 7 genes? i. What is the probability that an individual in the F2 generation would be pure-breeding (i.e. is homozygous at all 7 loci)? [Hint: this is an “and” calculation since it must be homozygous at each of the 7 loci. ii. What is the probability that an individual in the F3 generation would…arrow_forward
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