Chapter 3 Quiz

At which tropic level do organisms use a process that produces oxygen as a waste product? A) Producers B) Decomposers C) Primary consumers D) Secondary consumers E) Tertiary consumers

A

Autotrophs . . . A) Use photosynthesis B) Are able to survive without oxygen C) Are primary consumer D) Are at the top of the food chain E) Cannot assimilate carbon

A

Beginning at the lowest trophic level, arrange the following food chain found on the Serengeti Plain of Africa in the correct sequence. A) Shrubs → Gazelles → Cheetahs → Decomposers B) Shrubs → Decomposers → Gazelles → Cheetahs C) Shrubs → Decomposers → Cheetahs → Gazelles D) Gazelles → Decomposers → Cheetahs → Shrubs E) Decomposers → Cheetahs → Shrubs → Gazelles

A

Human interaction with the nitrogen cycle is primarily due to . . . A) The leaching of nitrates into terrestrial ecosystems B) The breakdown of ammonium into ammonia for industrial uses C) The interruption of the mineralization process in urban areas D) The acceleration of the nitrification process in aquatic ecosystems E) The decreased assimilation of ammonium and nitrates

A

If gross primary productivity in a wetland is 3 kg C/m2/year and respiration is 1.5 kg C/m2/year, what is the net primary productivity of the wetland? A) 1.5 kg C/m²/year B) 2 kg C/m²/year C) 3 kg C/m²/year D) 4.5 kg C/m²/year E) Impossible to determine from the given information

A

Phosphorus . . . A) Is a limiting nutrient in many aquatic systems B) Has an important gaseous phase C) Is easily lost from soils due to leachings D) Is often produced by volcanic eruptions E) Changes chemical form often during its biogeochemical cycle

A

After a severe drought, the productivity in an ecosystem took many years to return to pre-drought conditions. This observation indicates that the ecosystem has . . . A) High resilience B) Low resilience C) High resistance D) Low resistance E) Equal resilience and resistance

B

An ecosystem has an ecological efficiency of 10 percent. If the producer level contains 10,000 kilocalories of energy, how much energy does the tertiary consumer level contain? A) 1 kcal B) 10 kcal C) 100 kcal D) 1,000 kcal E) 10,000 kcal

B

Human construction of buildings and pavement affect the hydrological cycle by . . . I. Increasing runoff II. Increasing evaporation III. Increasing percolation A) I only B) I and II only C) I and III only D) II and III only E) III only

B

Research at Hubbard Brook showed that stream nitrate concentrations in two watersheds were ____________ before clear-cutting, and that after one watershed was clear-cut, its stream nitrate concentration was ____________. A) Similar/decreased B) Similar/increased C) Similar/same D) Different/increased E) Different/decreased

B

The gross primary productivity of an ecosystem is . . . A) The total amount of biomass B) The total energy captured by photosynthesis C) The energy captured after accounting for respiration D) The energy available to primary consumers E) The biomass of the producers

B

The waste product in photosynthesis is . . . A) Carbon dioxide B) Oxygen C) Glucose D) Water E) Energy

B

Which is NOT true about disturbances? A) They are caused by natural events such as hurricanes B) They occur only on short time scales C) They can cause complete destruction of an ecosystem D) Many result in no change in ecosystem productivity E) Some are due to anthropogenic causes

B

Which macronutrient is required by humans in the largest amounts? A) Calcium B) Nitrogen C) Sulfur D) Potassium E) Magnesium

B

Which biogeochemical cycle(s) does NOT have a gaseous component? I. Potassium II. Sulfur III. Phosphorus A) II only B) I and II ony C) III only D) II and III only E) I and III only

C

Which is a measure of how much a disturbance can affect the flows of energy and matter in an ecosystem? A) Diversity B) Intensity C) Resistance D) Resilience E) Homeostasis

C

An ecosystem that rapidly returns to its original state after a disturbance is . . . A) Resistant B) Vigorous C) Resilient D) Stable E) Adaptable

C

Haitian farmers are buying mango tree saplings for $10 each, and the full-grown trees produce $75 of fruit each year. If a farmer wishes to earn $1,500 per year when the trees are grown, how much will the farmer have to spend on saplings? A) $100 B) $150 C) $200 D) $750 E) $1,000

C

The average efficiency of energy transfer between trophic levels is approximately . . . A) 1 percent B) 4 percent C) 10 percent D) 40 percent E) 50 percent

C

The largest carbon pool is found in . . . A) Oceans B) The atmosphere C) Sedimentary rock D) Living organisms E) Fossil fuel

C

Which of the following could be a cause of decreased evapotranspiration? A) Increased precipitation B) Decreased runoff C) Increased percolation D) Increased vegetation E) Increased sunlight

C

A zebra is an example of . . . A) A secondary consumer B) A producer C) A detritivore D) A primary consumer E) A scavenger

D

At which trophic level are eagles that consume fish that eat algae? A) Producers B) Decomposers C) Primary consumers D) Secondary consumers E) Tertiary consumers

D

The intermediate disturbance hypothesis states that intermediate levels of disturbance will . . . A) Increase runoff B) Increase ecosystem nutrient cycling C) Decrease primary productivity D) Increase species diversity E) Decrease biomass

D

Which of the following is NOT an example of an abiotic component of an ecosystem? A) Water B) Minerals C) Sunlight D) Fungi E) Air

D

Which of the following is NOT characteristic of most ecosystems? A) Biotic components B) Abiotic components C) Recycling of matter D) Distinct boundaries E) A wide range of sizes

D

Which of the following processes is also known as ammonification? A) Nitrogen fixation B) Nitrification C) Assimilation D) Mineralization E) Denitrification

D

Which one of the following is fixed from the atmosphere by bacteria? A) Magnesium B) Phosphorus C) Sulfur D) Nitrogen E) Potassium

D

Acid rain is associated with which geochemical cycle? A) Potassium B) Calcium C) Carbon D) Phosphorus E) Sulfur

E

At which trophic level are dragonflies that consume mosquitoes that feed on herbivorous mammals? A) Producers B) Decomposers C) Primary consumers D) Secondary consumers E) Tertiary consumers

E

Ecosystem boundaries are . . . A) Based primarily on topographic features B) Boundaries to nutrient flows C) Never based on human created features D) Are only used for ecosystems smaller than a few square hectares E) Depend on many subjective factors

E

Roughly what percentage of incoming solar energy is converted into chemical energy by producers? A) 99 B) 80 C) 50 D) Between 5 and 20 E) 1

E

Small inputs of this substance, commonly a limiting factor in aquatic ecosystems, can result in algal blooms and dead zones. A) Dissolved carbon dioxide B) Sulfur C) Dissolved oxygen D) Potassium E) Phosphorus

E

The Hubbard Brook experminet showed that . . . A) The intermediate disturbance hypothesis is plausible B) Freshwater aquatic ecosystems are often very resilient C) River restoration can take many years to complete D) Evapotranspiration increases with more vegetation cover E) Deforestation increases nutrient runoff

E

The net primary productivity of an ecosystem is 1 kg C/m2/year, and the energy needed by the producers for their own respiration is 1.5 kg C/m2/year. The gross primary productivity of such an ecosystem would be . . . A) 0.5 kg C/m²/year B) 1.0 kg C/m²/year C) 1.5 kg C/m²/year D) 2.0 kg C/m²/year E) 2.5 kg C/m²/year

E

Which of the following statements about the carbon cycle is true? A) Carbon transfer from photosynthesis is in steady state with respiration and death B) The majority of dead biomass is accumulated in sedimentation C) Combustion of carbon is equivalent in mass to sedimentation D) Most of the carbon entering the oceans is from terrestrial ecosystems E) Carbon exchange between the atmosphere and terrestrial ecosystems is primarily an abiotic process

E