TLS Online TPP Program

#Question id: 12958


The Norway rat (Rattus Norvegicus), a widespread pest, was controlled for about a decade by the anticoagulant warfarin. This chemical substance, placed in food pellets, is absorbed by the intestinal tract and inhibits the clotting of blood. After a population decline for about 10 years, rat populations increased and stabilized. In one European population, as illustrated in the graph below, the percentage of rats resistant to warfarin has remained fairly stable over a number of years

Resistance to warfarin is governed by a dominant autosomal gene, R. More than 15 percent of the resistant animals are heterozygous at this locus (Rr). The table below indicates the response to warfarin and relative reproductive fitness of individuals that are homozygous or heterozygous for the dominant gene (R). The RR individuals have a 20-fold increase in vitamin K requirement over individuals.


Fitness is a measure of the reproductive success of a particular genotype. The highest fitness is 1.00.

The strong dependence of RR individuals on large quantities of vitamin K probably is responsible for

#Unit 10. Ecological Principles
  1. Their lowered fitness
  2. Their susceptibility to warfarin
  3. Their superiority to heterozygotes (Rr)
  4. Their increasing numbers in the population each generation
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TLS Online TPP Program

#Question id: 18227

#Unit 8. Inheritance Biology

You are conducting genetic linkage studies of an autosomal dominant disease. You are focused on two SSR markers that may be linked to each other and to the disease. Here is a family in which some individuals are affected:
 
Calculate LOD scores for linkage at θ = 0.1 between the disease and SSR62

TLS Online TPP Program

#Question id: 18228

#Unit 8. Inheritance Biology

You are conducting genetic linkage studies of an autosomal dominant disease. You are focused on two SSR markers that may be linked to each other and to the disease. Here is a family in which some individuals are affected:
 
Calculate LOD scores for linkage at θ = 0.1 between the disease and SSR93?

TLS Online TPP Program

#Question id: 18229

#Unit 8. Inheritance Biology

You are conducting genetic linkage studies of an autosomal dominant disease. You are focused on two SSR markers that may be linked to each other and to the disease. Here is a family in which some individuals are affected:
 
Calculate LOD scores for linkage at θ = 0.1 between SSR62 and SSR93

TLS Online TPP Program

#Question id: 18969

#Unit 8. Inheritance Biology

Consider the ABO “blood type” gene. This single gene has three alleles called A, B, and O. There are four resultant “blood types” (phenotypic classes), as follows:C
                               
Assume Hardy-Weinberg equilibrium. In Norway, the frequencies of the A and B alleles are 0.26 and 0.07, respectively. What is the frequencies of these six genotypes (AA, AO, BB, BO, AB, and OO);

TLS Online TPP Program

#Question id: 18970

#Unit 8. Inheritance Biology

Consider the ABO “blood type” gene. This single gene has three alleles called A, B, and O. There are four resultant “blood types” (phenotypic classes), as follows:
                                     
Assume Hardy-Weinberg equilibrium,  the frequencies of the A and B alleles are 0.26 and 0.07, respectively. What is the frequencies of the four blood types such as A, B, AB  and O in Norway;

TLS Online TPP Program

#Question id: 19025

#Unit 8. Inheritance Biology

Consider the ABO “blood type” gene. This single gene has three alleles called A, B, and O. There are four resultant “blood types” (phenotypic classes), as follows: C
                         
Assume Hardy-Weinberg equilibrium,  the frequencies of the A and B alleles are 0.26 and 0.07, respectively. You now examine the ABO blood types in a new population. You observe that the A, B, and O blood types all have equal frequencies in this population. What are the frequencies of the A and O alleles in this population?