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 4, Problem 31PDQ
The maternal-effect mutation bicoid(bcd)is recessive. In the absence of the bicoid protein product, embryogenesis is not completed. Consider a cross between a female heterozygous for the bicoid mutation (bcd+/bcd–) and a homozygous male (bcd–/bcd–)
(a) How is it possible for a male homozygous fur the mutation to exist?
(b) Predict the outcome (normal vs. failed embryogenesis) in the F1 and F2 generations of the cross described.
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In drosophila, a recessive mutation (m-) of a maternal effect gene results in an abnormal phenotype wherein homozygous (m-m-) females produce eggs that cannot support embryonic development. Homozygous (m-m-) males, however, can still produce viable sperm.
(A) Using m+ to denote a normal gene, determine the genotypes and phenotypes of the F1s produce by a cross between a heterozygous female and a recessive male.
(B) From the offspring, backcross the recessive female with the paternal strain. What are the genotypes and phenotypes of the F2s?
(C) If m-m- females produce useless eggs, then how are m-m- produced?
The maternal-effect mutation bicoid (bcd) is recessive. Inthe absence of the bicoid protein product, embryogenesis isnot completed. Consider a cross between a female heterozygousfor the bicoid mutation (bcd+/ bcd-) and a homozygousmale(bcd-/ bcd-).
How is it possible for a male homozygous for the mutationto exist?
In drosophila, a recessive mutation (m-) of a maternal effect gene results in an abnormal phenotype wherein homozygous (m-m-) females produce eggs that cannot support embryonic development. Homozygous (m-m-) males, however, can still produce viable sperm. Using m+ to denote a normal gene, determine the genotypes and phenotypes of the F1s produce by a cross between a heterozygous female and a recessive male. From the offspring, backcross the recessive female with the paternal strain.
1. What are the genotypes and phenotypes of the F2s?
2. If m-m- females produce useless eggs, then how are m-m- produced?
Chapter 4 Solutions
Essentials of Genetics (9th Edition) - Standalone book
Ch. 4 - CASE STUDY | But he isn't deaf Researching their...Ch. 4 -
CASE STUDY | But he isn’t deaf
Researching...Ch. 4 - CASE STUDY | But he isn't deaf Researching their...Ch. 4 - HOW DO WE KNOW? In this chapter, we focused on...Ch. 4 - Review the Chapter Concepts list on page 53. These...Ch. 4 - In Shorthorn cattle, coat color may be red, white,...Ch. 4 -
4. With regard to the ABO blood types in humans,...Ch. 4 - In foxes, two alleles of a single gene, P and p,...Ch. 4 - Three gene pairs located on separate autosomes...Ch. 4 - As in the plants of Problem 6, color may be red,...
Ch. 4 -
8. The following genotypes of two independently...Ch. 4 - Given the inheritance pattern of coat color in...Ch. 4 - A husband and wife have normal vision, although...Ch. 4 - In humans, the ABO blood type is under the control...Ch. 4 - In goals, development of the beard is due to a...Ch. 4 -
13. In cats, orange coal color is determined by...Ch. 4 - In Drosophila, an X-linked recessive mutation,...Ch. 4 - Another recessive mutation in Drosophila, ebony...Ch. 4 - While vermilion is X-linked in Drosophila and...Ch. 4 - In pigs, coat color may be sandy, red, or white. A...Ch. 4 - A geneticist from an alien planet that prohibits...Ch. 4 - In another cross, the frog geneticist from Problem...Ch. 4 - In cattle, coats may be solid white, solid black,...Ch. 4 - Consider the following three pedigrees, all...Ch. 4 - Labrador retrievers may be black, brown, or golden...Ch. 4 - Three autosomal recessive mutations in Drosophila,...Ch. 4 -
24. Horses can be cremello (a light cream...Ch. 4 - Pigment in the mouse is produced only when the C...Ch. 4 - Five human matings numbered 1–5 are shown in the...Ch. 4 - Two mothers give birth to sons at the same time at...Ch. 4 - In Dexter and Kerry cattle, animals may be polled...Ch. 4 - What genetic criteria distinguish a case of...Ch. 4 -
30. The specification of the anterior-posterior...Ch. 4 - The maternal-effect mutation bicoid(bcd)is...Ch. 4 -
32. Students taking a genetics exam were...Ch. 4 - In four o'clock plants, many flower colors are...Ch. 4 - Prob. 34PDQ
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