APES Unit 1 CED

NPP (Net Primary Productivity) =

Gross Primary Productivity - Plant Respiration (Rp)

Directions: Select the choice that best fits each statement. The following question(s) refer to the following processes. (A) Nitrification (B) Denitrification (C) Assimilation (D) Ammonification (E) Nitrogen fixation Ammonia is converted to nitrite, then to nitrate.

(A) Nitrification

Directions: Select the choice that best fits each statement. The following question(s) refer to the following processes. (A) Nitrification (B) Denitrification (C) Assimilation (D) Ammonification (E) Nitrogen fixation Plant roots absorb ammonium ions and nitrate ions for use in making molecules such as DNA, amino acids, and proteins.

(C) Assimilation

Directions: Select the choice that best fits each statement. The following questions(s) refer to the following elements. (A) Carbon (B) Sodium (C) Sulfur (D) Phosphorus (E) Potassium Guano from fish-eating birds is a commercial source of this element.

(D) Phosphorus

Which of the following is an example of a carbon sink? A: Deposition of organic matter on the deep ocean floor B: Clearing of trees in the Amazon forest C: Combustion of fossil fuels in power plants D: Decomposition of food waste by bacteria E: Nutrient uptake by the roots of grasses in a suburban lawn

A: Deposition of organic matter on the deep ocean floor

The diagrams above show an area that was once a pasture that has since undergone changes to the vegetation over time. Which of the following changes in the hydrologic cycle is most likely to occur as a result of the change in vegetation in the area? A: Increased infiltration B: Increased runoff C: Decreased transpiration D: Decreased precipitation

A: Increased infiltration (Vegetation, such as trees and shrubs, increases infiltration by increasing the time of water penetration in the soil.)

Based on the diagram above, which of the following processes reduces the amount of carbon dioxide in the atmosphere? A: Photosynthesis B: Cellular respiration C: Decomposition D: Burning of fossil fuels

A: Photosynthesis (During photosynthesis, primary producers use carbon dioxide in the atmosphere as the carbon source to produce organic carbon compounds.)

Based on the data in the table, if the number of snakes were to suddenly decrease, which of the following changes would most likely occur in the food web of this ecosystem? A: increase in number of shrews, decrease in number of hawks B: increase in number of hawks, decrease in number of shrews C: increase in number of grasshoppers, decrease in number of plants D: increase in number of spiders, decrease in number of plants

A: increase in number of shrews, decrease in number of hawks (Snakes feed on shrews so with less snakes, the population of shrews should increase. Hawks feed on snakes so with less overall food, the population of hawks should decrease.)

In a given ecosystem, producers convert solar energy into 15,000kcal of chemical energy stored in organic compounds. Which of the following is the most likely amount of energy available to secondary consumers? A: 1.5kcal B: 150kcal C: 1,500kcal D: 13,500kcal

B: 150kcal

Of the following organisms, which occupies the lowest trophic level? A: Spider B: Deer C: Lion D: Hawk E: Snake

B: Deer

The process in the hydrologic cycle in which water vapor is released from leaves into the atmosphere is called A: infiltration B: transpiration C: sublimation D: reflection E: percolation

B: transpiration

Which of the following best explains why terrestrial trophic pyramids usually do not have levels higher than tertiary consumers? A: Tertiary consumers are the largest organisms in an ecosystem and require the most space to survive. B: Plants can only perform photosynthesis during the day, so tertiary consumers cannot get enough energy from consuming plants. C: A large proportion of energy is lost as heat as it is transferred up the pyramid, so there is not enough energy available to support another level. D: Tertiary consumers are often indicator species and are the first to be affected by environmental disturbances.

C: A large proportion of energy is lost as heat as it is transferred up the pyramid, so there is not enough energy available to support another level. (As energy is transferred through trophic levels about 90% of the energy is lost to the environment as heat and thus there is not enough energy to support consumers past a third level, especially in terrestrial ecosystems.)

Which of the following pathways indicate how nitrogen is added to the largest nitrogen reservoir? A: Nitrifying bacteria and lightning B: Decomposing plant and animal material C: Denitrifying bacteria and volcanic activity D: Nitrates taken up by plant roots

C: Denitrifying bacteria and volcanic activity (The atmosphere is the major reservoir of nitrogen. About 78 percent of our atmosphere is composed of nitrogen gas. Denitrifying bacteria and volcanic activity release nitrogen gas._

Scientists calculated the net primary productivity at two different forest sites. Both forests have the same gross primary productivity. Forest A has a net primary productivity of 1,650kcal/m2/year, and forest B has a net primary productivity of 1,110kcal/m2/year. Which of the following statements is best supported by the data? A: Forest A has a higher rate of decomposition by bacteria than forest B. B: Forest A has more biodiversity than forest B. C: Forest A producers have lower rates of cellular respiration than forest B producers. D: Forest A producers have more biomass than forest B producers.

C: Forest A producers have lower rates of cellular respiration than forest B producers. (Since gross primary productivity is the same, forest B has a lower net primary productivity; therefore, it has a higher rate of cellular respiration.)

Photosynthesis is the major source of which of the following gases in Earth's atmosphere? A: CO2 B: H2O (water vapor) C: O2 D: H2 E: N2

C: O2

Which of the following best explains why decomposers in soils and water are important to ecosystems? A: They remove heavy metals. B: They store carbon dioxide. C: They recycle nutrients. D: They neutralize acid deposition. E: They produce more oxygen than they consume.

C: They recycle nutrients.

Which of the following best helps to explain why phosphorus is often a limiting factor in many ecosystems? A: There is usually a gaseous phase in the phosphorus cycle. B: Phosphorus cycles very quickly through environments. C: Under many conditions, phosphorus forms stable insoluble compounds. D: Phosphate is not readily taken up by plants. E: There are no anthropogenic sources of phosphorus.

C: Under many conditions, phosphorus forms stable insoluble compounds.

(Nitrogen Cycle) Denitrification

Conversion of nitrates into nitrogen gas

The net annual primary productivity of a particular wetland ecosystem is found to be 8,000 kcal/m2 per year. If respiration by the aquatic producers is 12,000 kcal/m2 per year, what is the gross annual primary productivity for this ecosystem, in kcal/m2 per year? A: 4,000 B: 8,000 C: 12,000 D: 20,000 E: 96,000

D: 20,000

The terrestrial biomes shown in the diagram above vary in net primary productivity. The explanation for the variation includes which of the following? I. Temperature II. Precipitation III. Longitude A: I only B: II only C: III only D: I and II only E: II and III only

D: I and II only

Elements that cycle in the environment and that also have a gaseous phase at some point in their cycle include which of the following? I. Carbon II. Phosphorus III. Sulfur A: I only B: III only C: I and II only D: I and III only E: I, II, and III

D: I and III only

Which of the following major storage reservoirs of carbon, stored in the form of carbon dioxide, is not represented in this diagram? A: Algae B: Soil bacteria C: The Moon D: The ocean

D: The ocean (Carbon dioxide from the atmosphere dissolves in the surface waters of the ocean; the ocean stores large amounts of carbon dioxide.)

NO3-

Nitrate

NO2

Nitrite

(Nitrogen Cycle) Nitrogen fixation

Process of converting nitrogen gas into ammonia

NH3

ammonia

(Nitrogen Cycle) Nitrification

ammonia is converted to nitrate ions (NO3-).

NH4+

ammonium ion

nitrogen reservoirs

atmosphere and soil

(Carbon) Human Affected Pathways

burning fossil fuels, transportation, deforestation, forest fires

CaCO3

calcium carbonate

CO2

carbon dioxide

CO3^-2

carbonate ion

H2CO3

carbonic acid

(Nitrogen Cycle) Ammonification

decomposers convert organic waste into ammonia

net primary productivity

equal to gross primary productivity minus respiration by producers

Carbon reservoirs include

fossil fuels and the atmosphere

Phosphorous does not have a _______ phase

gaseous

(Phosphorous) Human Affected Pathways

mining and extraction, fertilizer runoff

HNO3

nitric acid

N2

nitrogen gas

N2O

nitrous oxide

PO4^3-

phosphate ion

(Nitrogen Cycle) Assimilation

plants absorb the nitrogen includes nitrification and nitrogen fixation

Nitrogen and phosphorus are both nutrients...

required for plant growth.

(Nitrogen) Human Affected Pathway

runoff from fertilizers

phosphorous reservoirs

sedimentary rocks and the ocean

gross primary productivity

the total amount of solar energy captured by producers through photosynthesis over time