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 34P
The gene that likely controlled flower color (purple or white) in Mendel’s pea plants has also been identified. The flower color gene specifies a protein called bHLH required by cells to make three different enzymes (DFR, ANS, and 3GT) that function in the pathway shown in the accompanying figure, leading to synthesis of the purple pigment anthocyanin.
| a. | What is the most likely explanation for the difference between the dominant allele (P) and the recessive allele (p) of the gene responsible for these flower colors? |
| b. | Given the biochemical pathway shown, could a different gene have been the one governing Mendel’s flower colors? |
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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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