Question 1

The replacing forests with agricultural or urban areas can significantly affect the water cycle.Why is this?

Accepted Answer

A)  Less moisture is evapotranspired into the atmosphere after deforestation.
B)  The level of soil nutrients is lower after deforestation.
C)  The rate of evapotranspiration increases after deforestation.
D)  Cloud cover will increase after deforestation.E) A) and B)
F) C) and D)

Question 2

The process by which soil bacteria convert NH3 or NH4 to nitrate (NO3-) is called

Accepted Answer

A)  assimilation.
B)  denitrification.
C)  fixation.
D)  nitrification.
E)  ammonification.F) B) and D)
G) A) and B)

Question 3

Where are the largest reserves of carbon on the planet?

Accepted Answer

A)  soil and rocks
B)  plants,algae,and cyanobacteria
C)  rocks and fossil fuels
D)  volcanoes and hot springs
E)  the oceansF) B) and C)
G) C) and D)

Question 4

Most transpiration occurs from the sea.

Accepted Answer

A) True 
 B)False

Question 5

Primary production is generally highest in

Accepted Answer

A)  tundrA.
B)  desert.
C)  wetlands.
D)  tropical rain forests.
E)  tropical oceans.F) A) and C)
G) A) and D)

Question 6

In subarctic saltmarshes,scientists have found that the addition of calcium has no effect on productivity,but additional iron does increase productivity.In this example,iron

Accepted Answer

A)  is a precursor to calcium.
B)  stimulates evapotranspiration.
C)  biomagnifies in the marsh plants.
D)  is a limiting factor.
E)  blocks the effect of calcium.F) A) and D)
G) D) and E)

Question 7

Ecosystem ecology is primarily concerned with

Accepted Answer

A)  ecosystem stability.
B)  species interactions in various types of ecosystems.
C)  the synthesis of nutrients within ecosystems.
D)  patterns of species diversity within ecosystems.
E)  movement of energy and materials through ecosystems.F) B) and C)
G) A) and D)

Question 8

What do you think would result if aquatic species of nitrogen fixing cyanobacteria suffered dramatic population decreases?

Accepted Answer

A)  Algae populations would decline,but run off from industrial fixation would continue to provide enough nutrients to prevent their collapse.
B)  Both the aquatic and terrestrial populations of autotrophs would collapse,with the end result that all life would cease to exist.
C)  Algae populations would increase because they would have less competition for sunlight after the nitrogen fixing cyanobacteria were eliminated.
D)  There would be no change in aquatic autotroph populations because nitrogen fixation by cyanobacteria is negligible.E) All of the above
F) None of the above

Question 9

Most of the Earth's phosphorus is trapped in sedimentary rocks.

Accepted Answer

A) True 
 B)False

Question 10

What are the most important transformers of energy in ecosystems?

Accepted Answer

A)  detritivores.
B)  plants and algae.
C)  primary consumers.
D)  bacteria.
E)  secondary consumers.F) A) and E)
G) A) and B)

Question 11

The movement of chemicals through ecosystems is known as

Accepted Answer

A)  gross primary production.
B)  biogeochemical cycling.
C)  community ecology.
D)  net primary production.
E)  biomagnification.F) C) and E)
G) C) and D)

Question 12

A hectare of wheat fixes 32,000 kg of carbon per year through photosynthesis and uses 7,000 kg of carbon per year for cellular respiration.The net primary productivity of the wheat field is therefore _____ kg of carbon/hectare/year.

Accepted Answer

The answer of A hectare of wheat fixes 32,000 kg...

Question 13

The amount of CO2 in the atmosphere is stable over a period of one year.

Accepted Answer

A) True 
 B)False

Question 14

What percentage of the earth's atmosphere consists of nitrogen (N2) gas?

Accepted Answer

A)  0%
B)  10%
C)  28%
D)  44%
E)  78%F) A) and D)
G) B) and D)

Question 15

If gross primary production were to increase in an ecosystem,it would be reasonable to expect that

Accepted Answer

A)  nutrients would no longer be limiting factors.
B)  net primary production would not increase.
C)  cellular respiration would decrease.
D)  the trophic web would become more complex.
E)  the biomass of herbivores would increasE.F) D) and E)
G) B) and C)

Question 16

How do primary producers provide energy for the food chain?

Accepted Answer

A)  They break down organic molecules into inorganic elements.
B)  They make their own organic molecules via photo- or chemosynthesis.
C)  They receive energy from primary consumers.
D)  They pass on organic substances from secondary consumers.E) A) and B)
F) B) and C)

Question 17

Examine the map above (Figure 46.9) ,which shows indices of aquatic and terrestrial primary productivity based on concentrations of chlorophyll a.
Based on this index,primary productivity of aquatic systems:

Accepted Answer

A)  is equal at all latitudes.
B)  generally increases from the poles to the equator.
C)  is greatest in the open ocean.
D)  is usually high in warm,tropical seas.
E)  tends to be high near polar regions.F) D) and E)
G) A) and B)

Question 18

All living organisms require phosphorus for ATP.

Accepted Answer

A) True 
 B)False

Question 19

The process by which elevated nutrient levels lead to an overgrowth of algae and the subsequent depletion of water oxygen levels is known as

Accepted Answer

A)  succession.
B)  decomposition.
C)  eutrophication.
D)  assimilation
E)  biogeochemical cycling.F) A) and E)
G) B) and D)

Question 20

Animal biomass exceeds plant biomass in most ecosystems.

Accepted Answer

A) True 
 B)False

Exam 46: Ecosystem Ecology

Primary production is generally highest in

Correct AnswerverifiedShow Answer

How do primary producers provide energy for the food chain?

Correct AnswerverifiedShow Answer

The amount of CO2 in the atmosphere is stable over a period of one year.

Correct AnswerverifiedShow Answer

The replacing forests with agricultural or urban areas can significantly affect the water cycle.Why is this?

Correct AnswerverifiedShow Answer

What are the most important transformers of energy in ecosystems?

Correct AnswerverifiedShow Answer

Where are the largest reserves of carbon on the planet?

Correct AnswerverifiedShow Answer

Animal biomass exceeds plant biomass in most ecosystems.

Correct AnswerverifiedShow Answer

The process by which elevated nutrient levels lead to an overgrowth of algae and the subsequent depletion of water oxygen levels is known as

Correct AnswerverifiedShow Answer

A hectare of wheat fixes 32,000 kg of carbon per year through photosynthesis and uses 7,000 kg of carbon per year for cellular respiration.The net primary productivity of the wheat field is therefore _____ kg of carbon/hectare/year.

Correct AnswerverifiedShow Answer

If gross primary production were to increase in an ecosystem,it would be reasonable to expect that

Correct AnswerverifiedShow Answer

In subarctic saltmarshes,scientists have found that the addition of calcium has no effect on productivity,but additional iron does increase productivity.In this example,iron

Correct AnswerverifiedShow Answer

All living organisms require phosphorus for ATP.

Correct AnswerverifiedShow Answer

Most transpiration occurs from the sea.

Correct AnswerverifiedShow Answer

The movement of chemicals through ecosystems is known as

Correct AnswerverifiedShow Answer

What percentage of the earth's atmosphere consists of nitrogen (N2) gas?

Correct AnswerverifiedShow Answer

Ecosystem ecology is primarily concerned with

Correct AnswerverifiedShow Answer

Most of the Earth's phosphorus is trapped in sedimentary rocks.

Correct AnswerverifiedShow Answer

The process by which soil bacteria convert NH3 or NH4 to nitrate (NO3-) is called

Correct AnswerverifiedShow Answer

Examine the map above (Figure 46.9) ,which shows indices of aquatic and terrestrial primary productivity based on concentrations of chlorophyll a. Based on this index,primary productivity of aquatic systems:

Correct AnswerverifiedShow Answer

What do you think would result if aquatic species of nitrogen fixing cyanobacteria suffered dramatic population decreases?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

The amount of CO² in the atmosphere is stable over a period of one year.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

What percentage of the earth's atmosphere consists of nitrogen (N₂) gas?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The process by which soil bacteria convert NH₃ or NH₄ to nitrate (NO_3-) is called

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified