TLS Online TPP Program

#Question id: 3869


Which one of the following statements about E. coli RNA polymerase (core enzyme) is false?

#Unit 3. Fundamental Processes
  1. It can start new chains de novo or elongate old ones.

  2. It has no catalytic activity unless the sigma factor is bound.

  3. It uses nucleoside 5'-triphosphates as substrates.

  4. Its activity is blocked by rifampicin.

More Questions
TLS Online TPP Program

#Question id: 3423

#Unit 11. Evolution and Behavior

Following statement regarding divergent evolution?

A- Spreading of same species to different and isolated environments which blocks the gene flow among the distinct populations

B. vertebrate limb of whale and elephant is one example of divergent evolution

C- Both orthologous genes and paralogous genes can be said to display divergent evolution

D- Sympatric speciation leads to divergence of one species in to two are more descendant species

Which of the following combination of above statement are correct?

TLS Online TPP Program

#Question id: 3422

#Unit 11. Evolution and Behavior

Micro-evolution is the term used for changes in allele frequencies that occur over time.

A) It gives rise to changes in the gene pool, which results in few changes in the same species

B) It occur above species level

C) New addition, deletion in the genetic structure, resulting in the formation of new species

D) It changes occurs over short time scales

Which of the following combinations is correct?

TLS Online TPP Program

#Question id: 3421

#Unit 11. Evolution and Behavior

Following figure show fitness variation the presence of natural selection and frequency of genotype before natural selection. What will be effect on the frequency of phenotype? (Y axis- Frequency of genotype, X axis – phenotype)

TLS Online TPP Program

#Question id: 3420

#Unit 11. Evolution and Behavior

Following are key points about the effect of genetic drift:

A. Genetic drift is significant in small populations.

B. Genetic drift can cause allele frequencies to change in a pre-directed way.

C. Genetic drift can lead to a loss of genetic variation within populations.

D. Genetic drift can cause harmful alleles to become fixed.

Which one of the following combination of the above statements are true?

TLS Online TPP Program

#Question id: 3419

#Unit 11. Evolution and Behavior

Which of the following is correct statement?

A. Co-evolution occurs when two or more species reciprocally affect each other's evolution through the process of natural selection.

B. Co-evolution is likely to happen when different species have close ecological interactions with one another.

C. Plant and insect is classical example of co-evolution to maintain ecological interaction

D. Co-evolution is likely to evolution of similar trait in different species

TLS Online TPP Program

#Question id: 3418

#Unit 11. Evolution and Behavior

Which of the best explanation of directional natural selection occur by change in environmental condition?

A. Increase in the frequency of dark-colored mutants in polluted areas, became known as industrial melanism

B. Numerous insect pests become resistant to insecticides and numerous bacteria become resistant to antibiotics.

C. A plant that is too short may not be able to compete with other plants for sunlight. However, extremely tall plants may be more susceptible to wind damage

D- Beetles move into a new environment with patches of light-green moss and dark-green shrubs, both light and dark beetles might be better hidden (and survive better) than medium-green beetles