Genetics: From Genes to Genomes
6th Edition
ISBN: 9781259700903
Author: Leland Hartwell Dr., Michael L. Goldberg Professor Dr., Janice Fischer, Leroy Hood Dr.
Publisher: McGraw-Hill Education
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Chapter 2, Problem 12P
Among Native Americans, two types of earwax (cerumen) are seen, dry and sticky. A geneticist studied the inheritance of this trait by observing the types of offspring produced by different kinds of matings. He observed the following numbers:
| Offspring | |||
| Parents | Number of mating pairs | Sticky | Dry |
| sticky×sticky | 10 | 32 | 6 |
| sticky×dry | 8 | 21 | 9 |
| dry×dry | 12 | 0 | 42 |
| a. | How is earwax type inherited? |
| b. | Why are no 3:1 or 1:1 ratios present in the data shown in the chart? |
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Students have asked these similar questions
In Thomas Hunt Morgan's experiments examining the transmission of eye color in fruit-flies, he observed that when he crossed heterozyYgous red-eyed females to red-eyed males, 1/2 of the male offspring were white-eyed, while all of the female offspring are red-eved, Which of the
following best explains the results?
1/2 of the male offspring inherit a white-eye color allele from their heterozygous mothers. Since there is no eye color gene on the Y chromosome, their eyes are white.
1/2 of the male offspring inherit a Y-chromosome from their fathers. Since there is no eye color gene on the Y chromosome, their eyes are white.
All of the female offspring inherit a dominant, red-eyed allele from their mothers
A 3 to 1 ratio of dominant to recessive offspring are expected in a single factor cross
As a biologist, you complete a test cross between fly offspring to gain information about how two genes interact. You find that 20% of these test cross offspring are parental types and 80% are recombinant types. Which of the following is true based on these results?
a.
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The genes in question are likely located on different chromosomes
c.
There is a 100% frequency of recombination in this test cross
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In aliens, the genes A, B, C, D and E are dominant to their respective alleles a, b, c, d and e:
A = one eye a = two eyes
B = pointed ears b = round ears
C = red skin c = green skin
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E = square head e = triangular head
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A. 9/512
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Chapter 2 Solutions
Genetics: From Genes to Genomes
Ch. 2 - For each of the terms in the left column, choose...Ch. 2 - During the millennia in which selective breeding...Ch. 2 - Describe the characteristics of the garden pea...Ch. 2 - An albino corn snake is crossed with a...Ch. 2 - Two short-haired cats mate and produce six...Ch. 2 - Piebald spotting is a condition found in humans in...Ch. 2 - As a Drosophila research geneticist, you keep...Ch. 2 - A mutant cucumber plant has flowers that fail to...Ch. 2 - In a particular population of mice, certain...Ch. 2 - In humans, a dimple in the chin is a dominant...
Ch. 2 - Some inbred strains of the weedy plant Arabidopsis...Ch. 2 - Among Native Americans, two types of earwax...Ch. 2 - Imagine you have just purchased a black stallion...Ch. 2 - If you roll a die singular of dice, what is the...Ch. 2 - In a standard deck of playing cards, four suits...Ch. 2 - How many genetically different eggs could be...Ch. 2 - What is the probability of producing a child that...Ch. 2 - A mouse sperm of genotype a B C D E fertilizes an...Ch. 2 - Your friend is pregnant with triplets. She thinks...Ch. 2 - Galactosemia is a recessive human disease that is...Ch. 2 - Albinism is a condition in which pigmentation is...Ch. 2 - A cross between two pea plants, both of which grew...Ch. 2 - A third-grader decided to breed guinea pigs for...Ch. 2 - The self-fertilization of an pea plant produced...Ch. 2 - The achoo syndrome sneezing in response to bright...Ch. 2 - A pea plant from a pure-breeding strain that is...Ch. 2 - The following table shows the results of different...Ch. 2 - A pea plant heterozygous for plant height, pod...Ch. 2 - In the fruit fly Drosophila melanogaster, the...Ch. 2 - Based on the information you discovered in the...Ch. 2 - Considering the yellow and green pea color...Ch. 2 - What would have been the outcome the genotypic and...Ch. 2 - Recall that Mendel obtained pure-breeding with...Ch. 2 - The gene that likely controlled flower color...Ch. 2 - For each of the following human pedigrees,...Ch. 2 - Consider the pedigree that follows for cutis laxa,...Ch. 2 - A young couple went to see a genetic counselor...Ch. 2 - Huntington disease is a rare fatal, degenerative...Ch. 2 - Is the disease shown in the following pedigree...Ch. 2 - Figure 2.22 shows the inheritance of Huntington...Ch. 2 - Consider the cystic fibrosis pedigree in Figure...Ch. 2 - Prob. 42PCh. 2 - People with nail-patella syndrome have poorly...Ch. 2 - Midphalangeal hair hair on top of the middle...Ch. 2 - A man with Huntington disease he is heterozygous...Ch. 2 - Explain why disease alleles for cystic fibrosis CF...Ch. 2 - The following pedigree shows the inheritance of...
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