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TLS Online TPP Program

#Question id: 24579

MMR (mismatch repair) system functions in

#Unit 3. Fundamental Processes
  1. Only at methylated state
  2. Only at hemi-methylated state
  3. The transition period between hemimethylated to methylated state
  4. Only in hypermethylated state
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TLS Online TPP Program

#Question id: 13140

#Unit 10. Ecological Principles

One summer the moose population on Island was unusually high, and park naturalists noticed signs of malnutrition among the  adults.  The wolf population  was  fairly  low,  near  20.  That  winter,  for  the  first  time  in  many  years,  a substantial  number of seemingly healthy adult moose as well as calves and crippled animals were killed and eaten by wolves. This description is part of a general situation in which the wolf and moose populations
TLS Online TPP Program

#Question id: 13141

#Unit 10. Ecological Principles

Five similar populations of a herbaceous annual plant are monitored for three years; then, the numbers of individuals in populations I-IV are increased by an experimenter. Subsequent changes in the sizes of all the populations are shown in the graph below.

If size distributions of individuals do not vary among these populations, which of the following relationships best illustrates the occurrence of population regulation?
TLS Online TPP Program

#Question id: 13142

#Unit 10. Ecological Principles

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.
There is a substantial number of heterozygotes in the population. Which of the following is the best explanation of this observation?
TLS Online TPP Program

#Question id: 13143

#Unit 10. Ecological Principles

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.
In a population where warfarin is no longer applied, the expectation is that the
TLS Online TPP Program

#Question id: 13144

#Unit 8. Inheritance Biology

Shell coiling of the snail Limnaea peregra(genetic maternal effect)  the shell coils (s+s+) which is termed dextral coiling, while some snails exhibiting sinistral coiling (ss). The allele for dextral (s +) is dominant over the allele for sinistral (s). If a male homozygous for dextral alleles (s+s+) is crossed with a female homozygous for sinistral alleles (ss) all of the F1 are heterozygous (s+s) and have a sinistral shell. If these F1 snails are self-fertilized, what is the phenotype of the F2 snail?
TLS Online TPP Program

#Question id: 13145

#Unit 8. Inheritance Biology

We can construct a genetic map by considering the recombination frequencies for each pair of genes. The recombination frequency between a and b is 50%, a and c is 50%, and b and c is 20%. What will be the correct prediction about this statements;
a)  Recombination frequency between genes a and b and gene a and c is expected with independent assortment
b) The genes a and b and gene a and c may either be on different chromosomes or be very far apart on the same chromosome;  so we will place them in different linkage groups
c) The gene b and c are linked
d) The gene b and c are unlinked
Which of the following is the correct sequence?