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 22, Problem 12P
Two alleles at one locus produce three distinct
| a. | Derive a formula to express this relationship. (Let n equal the number of genes.) |
| b. | Each of the most extreme phenotypes for a trait determined by two alleles at one locus are found in a proportion of 1/4 in the F2 generation. If two alleles of two genes determine the trait, each extreme phenotype will be present in the F2 as 1/16 of the population. In common wheat (Triticum aestivum), kernel color varies from red to white and the genes controlling the color act additively, that is, alleles for each gene are incompletely dominant and each gene contributes equally to the color. A true-breeding red variety is crossed to a true-breeding white variety, and 1/256 of the F2 have red kernels and 1/256 have white kernels. How many genes control kernel color in this cross? |
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Chapter 22 Solutions
Genetics: From Genes to Genomes
Ch. 22 - Choose the best matching phrase in the right...Ch. 22 - Suppose you grew genetically identical dandelion...Ch. 22 - How can each of the following be used in...Ch. 22 - Two different groups of scientists studying a rare...Ch. 22 - Which of the following statements would be true of...Ch. 22 - Studies have indicated that for pairs of twins...Ch. 22 - Prob. 7PCh. 22 - Prob. 8PCh. 22 - Table 22.2 lists concordance values for MZ and DZ...Ch. 22 - Prob. 10P
Ch. 22 - Prob. 11PCh. 22 - Two alleles at one locus produce three distinct...Ch. 22 - In a certain plant, leaf size is determined by...Ch. 22 - Compare and contrast the use of SNP genotyping: i...Ch. 22 - Explain the similarities and differences between...Ch. 22 - In Fig. 22.14c, the fw2.2 causal gene was...Ch. 22 - Among the most prevalent pathologies that afflict...Ch. 22 - Human geneticists have found the Finnish...Ch. 22 - Canavan disease, caused by homozygosity for a...Ch. 22 - In GWAS analysis, because of the existence of LD...Ch. 22 - In Fig. 22.15: a. Why do some chromosomes in the...Ch. 22 - Consider the triangle diagram shown in Fig. 22.17....Ch. 22 - Prob. 23PCh. 22 - You conduct a Case/Control study comparing the...Ch. 22 - Prob. 25PCh. 22 - ALS amyotrophic lateral sclerosis is a rare, fatal...Ch. 22 - Through GWAS explorations, scientists have...Ch. 22 - In domesticated dogs, size has a high...Ch. 22 - Suppose a GWAS investigation found a particular LD...Ch. 22 - In 2008, Time magazine named as its invention of...
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- Imagine that two unlinked autosomal genes with simple dominance code in goats for size, where L is large and l is small, and for color, where R is red and r is tan. If a small, tan male goat mates with a large, red female goat of an unknown genotype, what is the probability that they would produce small, tan offspring?arrow_forwardGiven a cross between these two parents: BbCcDDEEFfGgHhjj x BbCcddEeFfGgHHjj where traits B, E, H, J exhibit Mendelian inheritance; C, and F exhibit incomplete dominance; D, and G exhibit co-dominance answer the following: What proportion of the offspring will phenotypically resemble the first parent? What proportion of the offspring will genotypically resemble the second parent? How many phenotypes can be expected from the cross?arrow_forwardTwo pumpkins plants have the following genotype: EeFfGg and EeFfGg. Assume genes E, F and G are independently assorting. How probable is this most probable phenotype of offspring of these pumpkins plants?arrow_forward
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