23
Why does grouping terrestrial organisms into biomes obscure diversity?
  1. Biomes groups terrestrial organisms only on the basis of similar habitat conditions.
  2. Organisms belonging to a similar biome have dissimilarities in their makeup.
  3. There is variation within different types of biomes that biome categorization does not capture.
  4. Terrestrial biomes are defined based only on the growth form of the dominant vegetation.
24
Why are mesocosm and microcosm experiments not considered to represent the true nature of ecosystems?
  1. The ecosystem is either recreated or partitioned in both the experiments, which may alter the dynamics of the ecosystem the experiments are aiming to analyze.
  2. In both the experiments, dynamics of the ecosystem may get altered due to differences in species numbers and diversity although there are no alterations in the environment.
  3. In both the experiments, the ecosystem is recreated which may alter the dynamics of the ecosystem the experiments are aiming to analyze.
  4. Altering a natural ecosystem through partitioning, which occurs in both the experiments may change its dynamics due to differences in species numbers and diversity.
25
If a scientist wanted to monitor a desert food chain, what type of model might they develop and why?
  1. An analytical model would be ideal because they can address simple, linear ecosystem components that are mathematically complex.
  2. A simulation model would be ideal because they can address simple, linear systems that are mathematically complex.
  3. An analytical model would be ideal as they are considered ecologically more realistic than any other model.
  4. A simulation model would be ideal because it uses numerical techniques to solve problems and visualize the complex relationships that exist in the ecosystem.
26
Compare and contrast food chains and food webs. What are the strengths of each concept in describing ecosystems?
  1. Both food chain and food web follow a single path as energy is transferred in an ecosystem. Food chains are easier to follow and experiment with but less accurate whereas food webs are more holistic and complex.
  2. Both food web and food chain describe energy transfer dynamics in an ecosystem. Food chains are non-linear systems which are easier to follow and experiment with whereas food webs are linear, holistic and can be directly used as input for simulation models.
  3. Both food chain and food web follow a single path as energy is transferred in an ecosystem. Food chains are linear systems, easier to follow and used directly as input for simulation models, whereas food webs are non-linear, accurate, holistic and flexible for analytical modeling.
  4. Both food web and food chain describe energy transfer dynamics in an ecosystem. Food chains are linear systems, easier to follow and experiment with whereas food webs are non-linear, accurate and holistic and can be directly used as input for simulation models.
27
Name one natural and one human-related type of disturbance. Why are they of concern to conservationists?
  1. Lightening is a type of natural disturbance whereas pollution is a human related disturbance. Both are of concern to conservationists because they affect the entire ecosystem.
  2. Fire is a type of natural disturbances whereas agriculture is a human related disturbance. Both types are of concern to conservationists because ecosystems cannot bounce back from a disturbance.
  3. Pollution is a type of natural disturbance whereas lightening is a human related disturbance. Both are of concern to conservationists because they alter ecosystems.
  4. Lightening is a type of natural disturbance whereas pollution is a human related disturbance. Both are of concern to conservationists because they alter ecosystems.
28
Compare grazing and detrital food webs. Why would they both be present in the same ecosystem?
  1. The primary producers of detrital food webs are decomposers whereas those of grazing food webs are non-photosynthetic. Both primary producers support different components of the ecosystem.
  2. The primary producers of detrital food webs are photosynthetic whereas those of grazing food webs are decomposers. Both primary producers support different components of the ecosystem.
  3. The primary producers of detrital food webs are decomposers whereas those of grazing food webs are photosynthetic. Both primary producers support different components of the ecosystem.
  4. The primary producers of detrital food webs are chemoautotrophs whereas those of grazing food webs are photosynthetic. Both primary producers support different components of the ecosystem.
29
How does the amount of food that endotherms and ectotherms consume compare with their net production efficiency (NPE)?
  1. The amount of food eaten by an animal does not affect its net production efficiency (NPE).
  2. Endotherms use more energy compared to ectotherms due to energy loss by respiration and heat.
  3. Both endotherms and ectotherms use the same energy from food.
  4. Ectotherms use more energy compared to endotherms due to energy loss by respiration and heat.
30
Compare the three types of ecosystem pyramids and how well they describe ecosystem structure. Identify which ones can be inverted and give a specific example of an inverted pyramid for each.
  1. The three types of ecosystem pyramids are pyramids of energy, number and biomass out of which number and energy pyramids can be inverted. Examples of inverted pyramids of number and energy are temperate forests in summer and phytoplankton in the English Channel respectively.
  2. The three types of ecosystem pyramids are pyramids of energy, number and biomass out of which number and biomass pyramids can be inverted. Examples of inverted pyramids of number and biomass are temperate forests in summer and phytoplankton in the English Channel respectively.
  3. The three types of ecosystem pyramids are pyramids of energy, number and biomass out of which number and biomass pyramids can be inverted. Examples of inverted pyramids of number and biomass are temperate forests in summer and Silver Springs ecosystem in Florida respectively.
  4. The three types of ecosystem pyramids are pyramids of energy, number and biomass out of which number and biomass pyramids can be inverted. Examples of inverted pyramids of number and biomass are grasslands in summer and phytoplankton in the English Channel respectively.
31
Why do scientists more commonly analyze net primary productivity compared with gross primary productivity?
  1. Net primary productivity incorporates features like production at present and next trophic levels, whereas gross primary productivity does not.
  2. Net primary productivity is the rate at which photosynthetic primary producers incorporate energy from the sun.
  3. As net primary productivity is the energy content available to the organisms of the next trophic level.
  4. As respiration and heat loss uses energy of the primary producer, therefore, net primary productivity is what is actually available to primary consumers.
32
Describe nitrogen fixation and why it is important to agriculture.
  1. The process of nitrate formation from ammonia is called nitrogen fixation. It improves agricultural production as nitrogen is required by plants for nucleotide and protein formation.
  2. The process of nitrogen being bonded to organic molecule is called nitrogen fixation. It improves the crop yield by allowing the plants to compete with weeds.
  3. The reduction of nitrates back to nitrogen gas is called nitrogen fixation. It improves agricultural production as nitrogen is required by plants for nucleotide and protein formation.
  4. The process of nitrogen being bonded into organic molecules is called nitrogen fixation. It improves agricultural production as nitrogen is required by plants for nucleotide and protein formation.
33
How do agricultural animals such as cattle raise atmospheric carbon levels? What is a side effect?
  1. Cattle produce carbon monoxide, which when inhaled can cause death.
  2. Cattle produce carbon monoxide, which is a major contributor to global warming.
  3. Agricultural animals increase the amount of greenhouse gases by producing carbon dioxide and methane, so they contribute to global warming.
  4. Agricultural animals increase the amount of greenhouse gases by producing ozone, which contributes to global warming.
34
What form of sulfur is found in the atmosphere and how does it leave the atmosphere?
  1. hydrogen sulfide, which leaves the atmosphere as weak sulfur dioxide rain
  2. sulfur dioxide, which leaves the atmosphere as weak sulfur dioxide rain
  3. hydrogen sulfide, which leaves the atmosphere as weak sulfuric acid rain
  4. sulfur dioxide, which leaves the atmosphere as weak sulfuric acid rain