Genetics: Analysis and Principles
6th Edition
ISBN: 9781259616020
Author: Robert J. Brooker Professor Dr.
Publisher: McGraw-Hill Education
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Chapter 28, Problem 23CONQ
With regard to heterosis, is each of the following statements consistent with the dominance hypothesis, the overdominance hypothesis, or both?
A. Strains that have been highly inbred have become monomorphic for one or more recessive alleles that are somewhat detrimental to the organism.
B. Hybrid vigor occurs because highly inbred strains are monomorphic for many genes, whereas hybrids are more likely to be heterozygous for those same genes.
C. If a gene exists in two alleles, hybrids are more vigorous because heterozygosity for the gene is more beneficial than homozygosity of either allele.
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Chapter 28 Solutions
Genetics: Analysis and Principles
Ch. 28.1 - 1. Which of the following is an example of a...Ch. 28.1 - 2. Saying that a quantitative trait follows a...Ch. 28.2 - The variance is a. a measure of the variation...Ch. 28.2 - 2. Which of the following statistics is used to...Ch. 28.3 - 1. For many quantitative traits, genotypes and...Ch. 28.4 - A QTL is a __________ where one or more genes...Ch. 28.4 - 2. To map QTLs, strains are crossed that differ...Ch. 28.5 - 1. In a population of squirrels in North Carolina,...Ch. 28.5 - Prob. 2COMQCh. 28.5 - 3. One way to estimate narrow-sense heritability...
Ch. 28.6 - 1. For selective breeding to be successful, the...Ch. 28.6 - Prob. 2COMQCh. 28 - Give several examples of quantitative traits.How...Ch. 28 - 2. At the molecular level, explain why...Ch. 28 - 3. What is a normal distribution? Discuss this...Ch. 28 - 4. Explain the difference between a continuous...Ch. 28 - What is a frequency distribution? Explain how such...Ch. 28 - 6. The variance for weight in a particular herd of...Ch. 28 - Two different varieties of potato plants produce...Ch. 28 - 8. If , would you conclude that a positive...Ch. 28 - Prob. 9CONQCh. 28 - When a correlation coefficient is statistically...Ch. 28 - 11. What is polygenic inheritance? Discuss the...Ch. 28 - What is a quantitative trait locus (QTL)? Does a...Ch. 28 - 13. Let’s suppose that weight in a species of...Ch. 28 - Prob. 14CONQCh. 28 - 15. From an agricultural point of view, discuss...Ch. 28 - Many beautiful varieties of roses have been...Ch. 28 - 17. In your own words, explain the meaning of the...Ch. 28 - 18. What is the difference between broad-sense...Ch. 28 - The heritability for egg weight in a group of...Ch. 28 - In a fairly large population of people living in a...Ch. 28 - When artificial selection is practiced over many...Ch. 28 - 22. Discuss whether a natural population of wolves...Ch. 28 - 23. With regard to heterosis, is each of...Ch. 28 - Here are data for height and weight among 10 male...Ch. 28 - 2. The abdomen length (in millimeters) was...Ch. 28 - 3. You conduct an RFLP analysis of head weight in...Ch. 28 - 5. Let’s suppose that two strains of pigs differ...Ch. 28 - Prob. 6EQCh. 28 - In a wild strain of tomato plants, the phenotypic...Ch. 28 - The average thorax length in aDrosophilapopulation...Ch. 28 - 9. In a strain of mice, the average 6-week body...Ch. 28 - Prob. 10EQCh. 28 - 11. A danger in computing heritability values from...Ch. 28 - For each of the following relationships,...Ch. 28 - An animal breeder had a herd of sheep with a mean...Ch. 28 - The trait of blood pressure in humans has a...Ch. 28 - Discuss why heritability is an important...Ch. 28 - From a biological viewpoint, speculate as to why...Ch. 28 - 3. What is heterosis? Discuss whether it is caused...
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