The example of extended lactose tolerance in humans tell us that
A. it is entirely under genetic control; researchers agree that the environment plays no role in its development.
B. it is one of many aspects of human biology governed by both genes and by phenotypical adaptation to environmental conditions.
C. the production of the enzyme lactase and the ability to tolerate milk remain the same among all human populations.
D. people cannot increase their lactose tolerance, thereby discounting the theory of phenotypical adaptation.
E. a simple genetic trait accounts for the ability to digest milk.
Question 2
Which of these statements is NOT true?
A. Genetic drift can operate in any population, large or small.
B. Fixation due to genetic drift is more rapid in large populations.
C. Genetic drift is a mechanism of genetic evolution.
D. Random genetic drift is a change in allele frequency that results from chance.
E. Alleles can be lost by chance rather than because of any disadvantages they confer.
Lactose Operon
The flow of genetic information in a typical cell
Partial genetic map of E. coli
Common Indicators for Genetic Counseling Referral
Example of a genetic pedigree of the autosomal recessive disease cystic fibrosis
Example of a genetic pedigree of the autosomal dominant disease Marfan syndrome