TLS Online TPP Program

#Question id: 766


With respect to microRNAs, which, if any, of the following statements, is true?

#Unit 1. Molecules and their Interaction Relevant to Biology
  1. MicroRNA is a generic term that covers all tiny RNAs, ones that are less than 35 nucleotides long when mature.

  2. MicroRNA genes often occur in gene clusters within introns of protein-coding genes and are usually transcribed by RNA polymerase II.

  3. MicroRNAs regulate target genes by binding to complementary sequences on one DNA strand of the target gene.

  4. MicroRNAs normally regulate the expression of just a single target gene.

More Questions
TLS Online TPP Program

#Question id: 12341

#Unit 10. Ecological Principles

The figure shows population growth trajectories over time (as indicated by the arrows) of two stored-grain beetle  species  when  grown  together  under  constant  conditions.  Three  experiments  were  performed  that  differed only in the initial densities of the two species. Which of the following is the best interpretation of the experimental results?


TLS Online TPP Program

#Question id: 12342

#Unit 10. Ecological Principles

Which of the following is a biological attribute that would most likely allow a species to become cosmopolitan in distribution?

TLS Online TPP Program

#Question id: 12343

#Unit 10. Ecological Principles

Hybrids between some related species of plants are sterile because the parent plants had different chromosome numbers. Occasionally the chromosome number of such a hybrid  plant doubles spontaneously. Which of the following best describes the descendants of those plants with the double chromosome number?

TLS Online TPP Program

#Question id: 12344

#Unit 10. Ecological Principles

The concept of punctuated equilibrium refers to

TLS Online TPP Program

#Question id: 12345

#Unit 10. Ecological Principles

Shannon's index of diversity is calculated using the equation below, where pi is the proportion of the ithShannon's index of diversity is calculated using the equation below, where pi is the proportion of the ith species and ln is natural logarithm. For a community with a given number of species, which of the following statements is true? species and ln is natural logarithm. For a community with a given number of species, which of the following statements is true?


TLS Online TPP Program

#Question id: 12346

#Unit 10. Ecological Principles

The schematic below shows the relationship between survivorship with age (relative to maximum lifespan) in Species 1 (dashed line) and Species 2 (solid line). Which of the following inferences is compatible with this figure?