TLS Online TPP Program

#Question id: 2781


How many genes are estimated to be in the human genome?

#Unit 2. Cellular Organization
  1. 21,000

  2. 35,000

  3. 75,000

  4. 100,000

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TLS Online TPP Program

#Question id: 12960

#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.
Which of the following is most likely correct concerning the gene for resistance to warfarin? 

TLS Online TPP Program

#Question id: 12961

#Unit 10. Ecological Principles

Refer to the following experiment, which is designed to test the co evolutionary relationships among an unpalatable butterfly (the  monarch),  a  palatable  butterfly  (the  viceroy),  and  a  butterfly  predator  (the  jay).  Monarch butterflies are reared on three diets: milkweed (their natural food), cabbage, and cabbage treated with an extract from milkweed leaves. Viceroy butterflies, mimics of monarchs, also are reared on three diets: willows (their natural food), cabbage, and cabbage treated with an extract from milkweed leaves. In trial 1 of the first experiment, adult butterflies reared on a particular diet are presented one at a  time  at  1-hour  intervals  to  jays  and  the  jays  are  allowed  to  feed.  Each jay is  fed  until  it refuses to eat the butterfly presented, but no more than 12 butterflies are presented to a jay during a particular test. Five birds are used for each test; therefore, up to 60 butterflies can be consumed for each diet test. The observer records the actual number of butterflies  eaten. In trial 2, the experiment is repeated 2 weeks later. In the second experiment, the butterflies are reared on the same diets as in experiment 1. However, when they are offered to jays, some jays receive a monarch  reared  on  milkweed  before  being  offered  the  butterflies  reared  on  the  experimental  diets;  the  other  group  of jays is  first given a viceroy reared on willow before being  offered the butterflies reared on the experimental diets. The initial butterfly offered is included in the total number eaten, but no more than 12 butterflies are presented to each jay.

The data in the table indicate which of the following?

TLS Online TPP Program

#Question id: 29082

#Unit 10. Ecological Principles

There are some major anthropogenic atmospheric gases causing the greenhouse effect, which of the following gas has the most powerful greenhouse effect?

TLS Online TPP Program

#Question id: 29083

#Unit 10. Ecological Principles

Relative absorption per ppm of increase is;
I- CO2
II- Methane 
III- Nitrous oxide
IV- Chlorofluorocarbon
Arrange in decreasing order

TLS Online TPP Program

#Question id: 29084

#Unit 10. Ecological Principles

Which of the following gases has the major contribution to global warming?

TLS Online TPP Program

#Question id: 11403

#Unit 10. Ecological Principles

Several categories of risk of species extinction have been defined. A species can be determined as critical endangered if there is considered to be