Answer the following:
1. A predatory wasp that feeds exclusively on herbivorous ants would be an example of a(n) ___ that is part of the _ trophic level.
A) carnivore; third
B) herbivore; second
C) carnivore; second
D) omnivore; third

2. If herbivores eat 200 kg of plants, and the total plant biomass is 1,000 kg, the _ efficiency is ___%.
A) assimilation; 80
B) consumption; 20
C) consumption; 80
D) assimilation; 20

3. Suppose two agents are introduced into soil: one that results in an increase in nitrification and another that results in an equal addition of denitrification. Compared to the soil before, the combination of equal amounts of nitrification and denitrification in the soil would result in a net increase in (hint â look at the reactants and the products)
A) NH4+
B) NO3â
C) N2O

The trophic levels are divided by the manner in which the energy is produced and consumed among the living organisms. The first trophic level is occupied by the autotrophs, which are the organisms that are able to produce their own food. The second trophic level is occupied by the organisms that feed upon the autotrophs, thus they are the herbivores, as well as the omnivores in partial sense. In this case we will have the ants at the second level. The third trophic level is reserved for the organisms that feed upon the organisms of the second trophic level, thus they are predators. In this case, we will have the wasp in the third trophic level.

2. B) consumption; 20

If there are herbivores and plants, the plants account for 1,000 kg in biomass, and the herbivores eat 200 kg of them, then the consumption is 20% of the total biomass. This kind of a scenario is able to support the whole population of herbivores without any problem, as there is much more food than they need. It will only become a problem if the population of herbivores starts to grow exponentially, and they start to consume all of the food and even require more, the population will collapse.

3. C) N20

The processes and nitrification and denitrification are very common, both in nature, and because of the human activity. The human activity has actually increased this process significantly. The main product of the nitrification-denitrification is the N2O. It is a vital product for the nitrogen cycle, and it is one that is increasing the atmospheric temperature, thus too much of it is not of best interest for anyone.