EBK BIOLOGY
6th Edition
ISBN: 8220106777640
Author: Maier
Publisher: PEARSON
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Chapter 13, Problem 2AAATB
Summary Introduction
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The PKU is present in the person those are homozygous recessive for this disease allele. The reasons for this disease allele can be present in various frequencies in those populations that can lead to mental retardation in homozygous person.
Introduction:
Genetic drift (allelic drift) can be defined as the variation in the frequency of an existing allele in a population due to an accidental sampling of organisms. Allele frequency of a population is the fraction of the copies of one gene which share a specific form. Reproductive isolation can be defined as the barrier created by the environment, such as a mountain range or river that does not allow mating between two groups of same species.
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Sickle cell anemia is caused by a recessive allele at a single gene. As we discussed in class, being a homozygote for the sickle cell allele is almost always lethal, but heterozygotes tend to be resistant against malaria although they have a mild form of anemia. Because of this heterozygote advantage, the allele for sickle cell anemia has a frequency of more than 10% in some human populations.
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a) What is the frequency of the cystic fibrosis allele in the Caucasian population? Show all your work and express your answer as a value between 0 and 1 rounded to two decimal places.
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Chapter 13 Solutions
EBK BIOLOGY
Ch. 13 - Define biological species.Ch. 13 - Prob. 2LTBCh. 13 - Prob. 3LTBCh. 13 - Prob. 4LTBCh. 13 - Prob. 5LTBCh. 13 - Prob. 6LTBCh. 13 - The biological definition of race corresponds to...Ch. 13 - All of the following statements support the...Ch. 13 - Similarity in skin color among different human...Ch. 13 - Prob. 10LTB
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