Campbell Biology: Custom Edition
18th Edition
ISBN: 9781323717271
Author: Urry, Cain, Wasserman, Minorsky, Reece
Publisher: PEARSON C
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Chapter 14, Problem 15TYU
EVOLUTION CONNECTION Over the past half century, there has been a trend in the United States and other developed countries for people to marry and Start families later in life than did their parents and grandparents. What effects might this trend have on the incidence (frequency) of late-acting dominant lethal alleles in the population?
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Looking to the future, what changes to the frequency of the sickle-cell allele do you envision as most likely, and why? (In other words, do you envision it becoming more common or less common in human populations?) What factors (technology, climate change, etc) might be driving those changes?
2) The year is 2050. The climate has continued to warm. Areas in northern Canada and Alaska are without snow or ice; the average annual temperature has risen and previously snow-covered areas are now shrub land and some temperate forests. What effect would such a climatic change have on the gene pool of the rabbits? All BUT ONE could apply.
A) The allelic frequency has most likely shifted to 85% GG and 15% gg.
B) The dominant allele in the gene pool would become G, the previously rare allele.
C) The allele for white, g, would be scarce and perhaps nonexistent in the population.
D) White rabbits would be at a disadvantage in terms of camouflage and would likely fall prey to predators.
Heterozygote advantage is an interesting condition in those individuals who have one of each allele (dominant and recessive) have a higher survival rate than those individuals who are either homozygous dominant or homozygous recessive. Sickle-cell anemia is such a genetic disease associated with the recessive allele. Normal homozygous individuals (SS) have normal blood cells that are easily infected with the malarial parasite. Thus, many of these individuals become very ill from the parasite and many die. Individuals homozygous for the sickle-cell trait (ss) have red blood cells that readily collapse when deoxygenated. Although malaria cannot grow in these red blood cells, individuals often die because of the genetic defect. However, individuals with the heterozygous condition (Ss) have some sickling of red blood cells, but generally not enough to cause mortality. In addition, malaria cannot survive well within these "partially defective" red blood cells. Thus, heterozygotes tend to…
Chapter 14 Solutions
Campbell Biology: Custom Edition
Ch. 14.1 - DRAW IT Pea plants heterozygous for flower...Ch. 14.1 - WHAT IF? List all gametes that could be made by a...Ch. 14.1 - MAKE CONNECTIONS In some pea plant crosses, the...Ch. 14.2 - Prob. 1CCCh. 14.2 - Two organisms, with genotypcs BbDD and BBDd, are...Ch. 14.2 - WHAT IF? Three characters (flower color, seed...Ch. 14.3 - What two properties, one structural and one...Ch. 14.3 - If a man with type AB blood marries a woman with...Ch. 14.3 - WHAT IF? A rooster with gray feathers and a hen...Ch. 14.4 - Beth and Tom each have a sibling with cystic...
Ch. 14.4 - Prob. 2CCCh. 14.4 - Prob. 3CCCh. 14.4 - MAKE CONNECTIONS In Table 14.1, note the...Ch. 14 - When Mendel did crosses of true-breeding purple-...Ch. 14 - DRAW IT Redraw the Punnett Square on The right...Ch. 14 - Inheritance patterns are often more complex than...Ch. 14 - Both members of a couple know that they are...Ch. 14 - DRAW IT Two pea plants heterozygous for the...Ch. 14 - A man with type A blood marries a woman with type...Ch. 14 - A man has six fingers on each hand and six toes on...Ch. 14 - DRAW IT A pea plant heterozygous for inflated pods...Ch. 14 - Flower position, stem length, and seed shape are...Ch. 14 - Hemochromatosis is an inherited disease caused by...Ch. 14 - The genotype of F1, individuals in a tetrahybrid...Ch. 14 - What is the probability that each of thc following...Ch. 14 - Prob. 9TYUCh. 14 - Prob. 10TYUCh. 14 - In tigers, a recessive allele of a particular gene...Ch. 14 - In maize (com) plants,a dominant allele I inhibits...Ch. 14 - The pedigree belowtraces the inheritance of...Ch. 14 - Imagine that you are a genetic counselor, and a...Ch. 14 - EVOLUTION CONNECTION Over the past half century,...Ch. 14 - SCIENTIFIC INQUIRY You are handed a mystery pea...Ch. 14 - Prob. 17TYUCh. 14 - SYNTHESIZE YOUR KNOWLEDGE Just for fun, imagine...
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