TLS Online TPP Program

#Question id: 2677


Why is the transcription of structural genes of the trp operon turned off in the presence of tryptophan?

#Unit 2. Cellular Organization
  1. Tryptophan is the repressor that binds to the operator, preventing transcription.

  2. The structural genes are used to make tryptophan, which would not be needed if tryptophan is available.

  3. Tryptophan has no effect on the transcription of the structural genes.

  4. Tryptophan RNA polymerase from finding the promoter of the trp operon, preventing structural gene transcription.

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TLS Online TPP Program

#Question id: 3364

#Unit 11. Evolution and Behavior

Which of the following equations represents the corresponding equilibrium for a locus with three alleles p, q and r of diploid individuals? (P, Q and R represent the frequencies of p, q and r, respectively)

TLS Online TPP Program

#Question id: 3365

#Unit 11. Evolution and Behavior

Consider a population of 10,000 individuals, of which 2500 are homozygotes (PP) and 3000 are heterozygotes (Pp) genotype. The frequency of allele p in the population is

TLS Online TPP Program

#Question id: 3366

#Unit 11. Evolution and Behavior

Red-Green color blindness is an X-linked recessive disorder. In a population which is in the Hardy-  Weinberg equilibrium, the incidence of occurrence of this in males is 2:2000. What will be the expected incidence of affected homozygous females?

TLS Online TPP Program

#Question id: 3367

#Unit 11. Evolution and Behavior

The largest unit within which gene flow can readily occur is a

TLS Online TPP Program

#Question id: 3368

#Unit 11. Evolution and Behavior

The origin of a new plant species by hybridization, coupled with accidents during nuclear division, is an example of

TLS Online TPP Program

#Question id: 3369

#Unit 11. Evolution and Behavior

Genetic drift refers to random changes in allele frequencies over time leads to following consequence

a. Loss of genetic diversity per generation   

b. change in allelic frequency just by chance 

c. It caused adaptive evolution

d. It one allele may reach to 0 frequency