Concepts of Genetics (12th Edition)
12th Edition
ISBN: 9780134604718
Author: William S. Klug, Michael R. Cummings, Charlotte A. Spencer, Michael A. Palladino, Darrell Killian
Publisher: PEARSON
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Chapter 9, Problem 16ESP
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 alleles (bcd+/bcd−) and a male homozygous for the mutation (bcd−/bcd−).
- (a) How is it possible for a male homozygous for 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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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.
(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?
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 9 Solutions
Concepts of Genetics (12th Edition)
Ch. 9 - Chlamydomonas, a eukaryoric green alga, may be...Ch. 9 - In aerobically cultured yeast, a petite mutant is...Ch. 9 - DNA in human mitochondria encodes 22 different...Ch. 9 - Prob. 4NSTCh. 9 - Why did Marcia choose mitochondrial testing to...Ch. 9 - Marcia saw an ad on television for ancestry DNA...Ch. 9 - How much importance should we place on the results...Ch. 9 - HOW DO WE KNOW? In this chapter, we focused on...Ch. 9 - Review the Chapter Concepts list on page 196. The...Ch. 9 - Streptomycin resistance in Chlamydomonas may...
Ch. 9 - A plant may have green, white, or green-and-white...Ch. 9 - In diploid yeast strains, sporulation and...Ch. 9 - Predict the results of a cross between ascospores...Ch. 9 - In Lymnaea, what results would you expect in a...Ch. 9 - In a cross of Lymnaea, the snail contributing the...Ch. 9 - In Drosophila subobscura, the presence of a...Ch. 9 - A male mouse from a true-breeding strain of...Ch. 9 - Consider the case where a mutation occurs that...Ch. 9 - What is the endosymbiotic theory, and why is this...Ch. 9 - In an earlier Problems and Discussion section (see...Ch. 9 - Mitochondrial replacement therapy (MRT) offers a...Ch. 9 - The specification of the anteriorposterior axis in...Ch. 9 - The maternal-effect mutation bicoid (bcd) is...Ch. 9 - (a) In humans the mitochondrial genome encodes a...Ch. 9 - Mutations in mitochondrial DNA appear to be...Ch. 9 - Researchers examined a family with an interesting...Ch. 9 - Payne, B. A. et al. (2013) present evidence that a...Ch. 9 - As mentioned in Section 9.3, mtDNA accumulates...Ch. 9 - Because offspring inherit the mitochondrial genome...
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