Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 997
TLS Online TPP Program

#Question id: 1022

Why are we concerned at all with monitoring emerging/reemerging diseases?

#Unit 4. Cell Communication and Cell Signaling

  1. These represent growing threats to human health that will require new scientific research and resources to effectively combat.

  2. Because globalization (greater trade and travel between countries) leads to more chances for spread of illnesses into new areas and populations. Monitoring these illnesses will help us to protect people.

  3. Because the speed of travel has increased greatly. With increased speed of travel, it is far more likely that a serious pathogenic threat from one area of the world can spread rapidly across the globe in a very fast manner. We need to monitor the occurrence of these illnesses to try to protect populations.

  4. All of the above.

More Questions
TLS Online TPP Program

#Question id: 12237

#Unit 10. Ecological Principles

Which of the following occurred first during the separation of the elements of Pangaea through continental drift? 
TLS Online TPP Program

#Question id: 12238

#Unit 10. Ecological Principles

The mussel Mytilus edulis thrives in saline habitats, in both the highly salty seawater of tidal zones and the less salty estuaries. This results in two kinds of populations: one adapted to the higher salt concentrations of the tidal zone, and one adapted to the lower salt concentrations of the estuary. It has been found that the more salt-tolerant populations have high frequencies of an allele that produces an enzyme involved in maintaining osmotic equilibrium. Conversely, estuarine mussels having the same enzyme seem to be disfavoured and have a much higher death rate than mussels without the allele. Adult estuarine populations do have lower frequencies of this allele. Each spring, large numbers of larvae from  the salty habitats pour into the estuaries.
The invasion of the seawater larvae would be expected to facilitate change in the genetic structure of the estuarine population by a process called
TLS Online TPP Program

#Question id: 12239

#Unit 10. Ecological Principles

The figures above show the results of an experiment in which two microbial species, A and B, were grown in three treatments. In treatment I, species A was grown alone. In treatment II, species B was grown alone. In treatment III, both species were grown together at the same starting densities as in (I) and (II). The results suggest the interaction is best described as
TLS Online TPP Program

#Question id: 12240

#Unit 10. Ecological Principles

Two plant species co-occur in a prairie. Species X always occurs near species Y. However, species    often occurs in isolation from species X and produces more seeds when alone than when growing next to species X. Which of the following interactions between species X and Y could generate this pattern?
TLS Online TPP Program

#Question id: 12241

#Unit 10. Ecological Principles

The process of speciation can be prevented by
TLS Online TPP Program

#Question id: 12242

#Unit 10. Ecological Principles

Small body size often allows animals to exploit desert habitats because it