Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 9244
TLS Online TPP Program

#Question id: 12462

For most terrestrial ecosystems, pyramids of numbers, biomass, and energy are essentially the same-they have a broad base and a narrow top. The primary reason for this pattern is that

#Unit 10. Ecological Principles
  1. Secondary consumers and top carnivores require less energy than producers.
  2. At each step, energy is lost from the system as a result of keeping the organisms alive. 
  3. As matter passes through ecosystems, some of it is lost to the environment.
  4. Biomagnification of toxic materials limits the secondary consumers and top carnivores.
More Questions
TLS Online TPP Program

#Question id: 2283

#Unit 2. Cellular Organization

Most cells are very small. A typical eukaryotic cell, both plant and animal, will occur in which of the following size ranges?
TLS Online TPP Program

#Question id: 13057

#Unit 13. Methods in Biology

Precision will be reduced, but yield will be increased
Optimisation of a PCR reaction is often a compromise between the competing demands for precision, efficiency and yield. Although the specific effects may vary, generally, increasing the annealing temperature will increase non-specific primer binding and reduce precision. Increasing the length of the elongation phase will reduce the proportion of incomplete newly-synthesised strands and therefore increase yield. In this case, the potential effect on efficiency is unclear. Increasing the elongation phase would increase the reaction time, but the time taken to ramp down to a lower annealing temperature would be reduced.
How primer concentration leads to decrease in PCR efficiency?
TLS Online TPP Program

#Question id: 29517

#Unit 6. System Physiology – Plant

Common cyanogenic glycoside and their source is given

Match them correctly
TLS Online TPP Program

#Question id: 9583

#Unit 6. System Physiology – Plant

 A mechanism known as the Q cycle accounts for most of the observations in which structure and reactions of plastoquinone that operate in,
TLS Online TPP Program

#Question id: 65

#Unit 1. Molecules and their Interaction Relevant to Biology

Identify which of the following pair is enantiomers, diastereomers or meso compounds.