Essentials of Genetics (9th Edition) - Standalone book
9th Edition
ISBN: 9780134047799
Author: William S. Klug, Michael R. Cummings, Charlotte A. Spencer, Michael A. Palladino
Publisher: PEARSON
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Chapter 7, Problem 16PDQ
Drosophila melanogaster has one pair of sex chromosomes (XX or XY) and three autosomes (chromosomes II, III, and IV). A genetics student discovered a male fly with very short (sh) legs. Using this male, the student was able to establish a pure- breeding stock of this mutant and found that it was recessive. She then incorporated the mutant into a stock containing the recessive gene black (b, body color, located on chromosome II) and the recessive gene pink (p, eye color, located on chromosome III). A female from the homozygous black, pink, short stock was then mated to a wild-type male. The F1 males of this cross were all wild type and were then backcrossed to the homozygous b, p, sh females. The F2 results appeared as shown in the following table, and no other
| Phenotype | Female | Male |
| wild | 63 | 59 |
| pink* | 58 | 65 |
| black, short | 55 | 51 |
| black, pink, short | 69 | 60 |
*Pink indicates that the other two traits are wild type (normal). Similarly, black, short offspring are wild type for eye color.
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Chapter 7 Solutions
Essentials of Genetics (9th Edition) - Standalone book
Ch. 7 -
CASE STUDY | Links to autism
As parents of an...Ch. 7 -
CASE STUDY | Links to autism
As parents of an...Ch. 7 - CASE STUDY | Links to autism As parents of an...Ch. 7 -
CASE STUDY | Links to autism
As parents of an...Ch. 7 -
HOW DO WE KNOW?
1. In this chapter, we focused on...Ch. 7 -
CONCEPT QUESTION
2. Review the Chapter Concepts...Ch. 7 - Describe the cytological observation that suggests...Ch. 7 - Why does more crossing over occur between two...Ch. 7 - Why is a 50 percent recovery of single-crossover...Ch. 7 - Why are double-crossover events expected less...
Ch. 7 - What is the proposed basis for positive...Ch. 7 - What three essential criteria must be met in order...Ch. 7 - The genes dumpy wings (dp), clot eyes (cl), and...Ch. 7 - Colored aleurone in the kernels of corn is due to...Ch. 7 - In the cross shown here, involving two linked...Ch. 7 - In a series of two-point map crosses involving...Ch. 7 -
13. Two different female Drosophila were...Ch. 7 -
14. In Drosophila, a cross was made between...Ch. 7 -
15. A cross in Drosophila involved the recessive,...Ch. 7 -
16. Drosophila melanogaster has one pair of sex...Ch. 7 -
17. Drosophila females homozygous for the third...Ch. 7 - In Drosophila, the two mutations Stubble bristles...Ch. 7 -
19. A female of genotype
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