Question 1

The "denitrification" reaction converts nitrate (NO3-)to nitrogen gas (N2)under aerobic conditions.

Accepted Answer

A) True 
 B)False  False

Question 2

High soil nutrient content usually leads to slower decomposition,because soil organisms have less need for nutrients of organic origin.

Accepted Answer

A) True 
 B)False  False

Question 3

The release of ammonium (NH4+)from decaying organic material is called ____________.

Accepted Answer

ammonification

Question 4

The process of denitrification is

Accepted Answer

A) energy-yielding and aerobic. 
B) energy-releasing and aerobic. 
C) energy-yielding and anaerobic. 
D) energy-releasing and anaerobic. 
E) energy-neutral and anaerobic. 
A) energy-yielding and aerobic. 
B) energy-releasing and aerobic. 
C) energy-yielding and anaerobic. 
D) energy-releasing and anaerobic. 
E) energy-neutral and anaerobic.

Question 5

Likens and Bormann found that over 90% of the nutrients in the Hubbard Brook Experimental Forest were in the soil organic matter.

Accepted Answer

A) True 
 B)False

Question 6

The end product of biological nitrogen fixation is

Accepted Answer

A) N2. 
B) NO3-. 
C) NO2-. 
D) NH3. 
E) None of the choices are correct. 
A) N2. 
B) NO3-. 
C) NO2-. 
D) NH3. 
E) None of the choices are correct.

Question 7

Clearcutting at Hubbard Brook Experimental Forest sharply

Accepted Answer

A) increased export of nitrate (NO3-)in stream water. 
B) decreased export of nitrate (NO3-)in stream water. 
C) increased rates of denitrification in soils. 
D) decreased deposition of ammonia (NH3)from the atmosphere. 
E) increased deposition of ammonia (NH3)from the atmosphere. 
A) increased export of nitrate (NO3-)in stream water. 
B) decreased export of nitrate (NO3-)in stream water. 
C) increased rates of denitrification in soils. 
D) decreased deposition of ammonia (NH3)from the atmosphere. 
E) increased deposition of ammonia (NH3)from the atmosphere.

Question 8

In aquatic ecosystems,leaves with high lignin content decompose

Accepted Answer

A) rapidly because lignin is a nutrient-rich compound. 
B) rapidly because lignin enhances colonization by decomposing fungi. 
C) slowly because lignin reduces colonization by decomposing fungi. 
D) slowly because lignin is a carbon-poor compound. 
E) slowly because lignin-containing leaves sink rapidly. 
A) rapidly because lignin is a nutrient-rich compound. 
B) rapidly because lignin enhances colonization by decomposing fungi. 
C) slowly because lignin reduces colonization by decomposing fungi. 
D) slowly because lignin is a carbon-poor compound. 
E) slowly because lignin-containing leaves sink rapidly.

Question 9

Pocket gophers change the nitrogen cycle in prairies because they

Accepted Answer

A) excavate nitrogen-rich subsoil to the surface. 
B) selectively remove nitrogen-fixing legumes from plant communities. 
C) bury nitrogen-rich organic material in their burrows. 
D) cultivate nitrogen-fixing bacteria in burrow chambers. 
E) excavate nitrogen-poor subsoil to the surface. 
A) excavate nitrogen-rich subsoil to the surface. 
B) selectively remove nitrogen-fixing legumes from plant communities. 
C) bury nitrogen-rich organic material in their burrows. 
D) cultivate nitrogen-fixing bacteria in burrow chambers. 
E) excavate nitrogen-poor subsoil to the surface.

Question 10

"Nitrogen fixation" refers to the conversion of

Accepted Answer

A) carbon compounds to nitrogen compounds. 
B) nitrogen gas (N2)to ammonia (NH2). 
C) ammonia (NH3)to nitrogen gas (N2). 
D) ammonium (NH4+)to nitrate (NO3-). 
E) ammonium (NH4+)to nitrite (NO2-). 
A) carbon compounds to nitrogen compounds. 
B) nitrogen gas (N2)to ammonia (NH2). 
C) ammonia (NH3)to nitrogen gas (N2). 
D) ammonium (NH4+)to nitrate (NO3-). 
E) ammonium (NH4+)to nitrite (NO2-).

Question 11

In stream ecosystems,nutrient retentiveness is

Accepted Answer

A) not related to spiraling length. 
B) positively related to spiraling length. 
C) inversely related to spiraling length. 
D) a logarithmic function of spiraling length. 
E) a power function of spiraling length. 
A) not related to spiraling length. 
B) positively related to spiraling length. 
C) inversely related to spiraling length. 
D) a logarithmic function of spiraling length. 
E) a power function of spiraling length.

Question 12

The rate of decomposition of leaf litter in woodlands can be strongly influenced by

Accepted Answer

A) moisture. 
B) nitrogen content. 
C) leaf toughness. 
D) All of the choices are correct. 
E) None of the choices are correct. 
A) moisture. 
B) nitrogen content. 
C) leaf toughness. 
D) All of the choices are correct. 
E) None of the choices are correct.

Question 13

Which of the following is NOT an assumption of the t-test?

Accepted Answer

A) Each sample is drawn from a population with a normal distribution. 
B) The two populations being compared have equal variances. 
C) The two populations being compared have equal means. 
D) All of each sample is drawn from a population with a normal distribution,the two populations being compared have equal variances,and the two populations being compared have equal means are assumptions. 
E) None of each sample is drawn from a population with a normal distribution,the two populations being compared have equal variances,and the two populations being compared have equal means are assumptions. 
A) Each sample is drawn from a population with a normal distribution. 
B) The two populations being compared have equal variances. 
C) The two populations being compared have equal means. 
D) All of each sample is drawn from a population with a normal distribution,the two populations being compared have equal variances,and the two populations being compared have equal means are assumptions. 
E) None of each sample is drawn from a population with a normal distribution,the two populations being compared have equal variances,and the two populations being compared have equal means are assumptions.

Question 14

Fungi and bacteria release nitrogen stored in dead tissue through a decomposition process called

Accepted Answer

A) nitrogen fixation. 
B) ammonification. 
C) denitrification. 
D) nitrification. 
E) nitrogen assimilation. 
A) nitrogen fixation. 
B) ammonification. 
C) denitrification. 
D) nitrification. 
E) nitrogen assimilation.

Question 15

The major pool of nitrogen in the atmosphere is the direct source of nitrogen for most organisms.

Accepted Answer

A) True 
 B)False

Question 16

Phosphorus is an important constituent of

Accepted Answer

A) DNA. 
B) bone tissue. 
C) RNA. 
D) ATP. 
E) All of the choices are correct. 
A) DNA. 
B) bone tissue. 
C) RNA. 
D) ATP. 
E) All of the choices are correct.

Question 17

Which of the following are nitrogen fixing organisms?

Accepted Answer

A) cyanobacteria 
B) leguminous plants 
C) alders 
D) All of the choices are correct. 
E) both cyanobacteria and leguminous plants 
A) cyanobacteria 
B) leguminous plants 
C) alders 
D) All of the choices are correct. 
E) both cyanobacteria and leguminous plants

Question 18

The release of nutrients from organic material in inorganic form is called _____________.

Accepted Answer

The answer of The release of nutrients from organic material...

Question 19

Spiraling length of nutrients in streams can be calculated as S = VT.In this equation,

Accepted Answer

A) V represents nutrient concentration,and T represents water temperature. 
B) V represents the speed of water flow,and T represents water temperature. 
C) V represents the speed of water flow,and T represents the time required for nutrients to cycle. 
D) V represents nutrient retentiveness,and T represents the time required for nutrients to cycle. 
E) V represents nutrient retentiveness,and T represents species diversity. 
A) V represents nutrient concentration,and T represents water temperature. 
B) V represents the speed of water flow,and T represents water temperature. 
C) V represents the speed of water flow,and T represents the time required for nutrients to cycle. 
D) V represents nutrient retentiveness,and T represents the time required for nutrients to cycle. 
E) V represents nutrient retentiveness,and T represents species diversity.

Question 20

Nitrogen enrichment of ecosystems by human activity is largely driven by

Accepted Answer

A) addition of nitrogen fertilizers. 
B) nitrogen pollution from burning of fossil fuels. 
C) nitrogen fixation by bacteria in landfills. 
D) Both addition of nitrogen fertilizers and nitrogen pollution from burning of fossil fuels. 
E) Both addition of nitrogen fertilizers and nitrogen fixation by bacteria in landfills. 
A) addition of nitrogen fertilizers. 
B) nitrogen pollution from burning of fossil fuels. 
C) nitrogen fixation by bacteria in landfills. 
D) Both addition of nitrogen fertilizers and nitrogen pollution from burning of fossil fuels. 
E) Both addition of nitrogen fertilizers and nitrogen fixation by bacteria in landfills.

Exam 19: Nutrient Cycling and Retention

The "denitrification" reaction converts nitrate (NO3-)to nitrogen gas (N2)under aerobic conditions.

High soil nutrient content usually leads to slower decomposition,because soil organisms have less need for nutrients of organic origin.

The release of ammonium (NH4+)from decaying organic material is called ____________.

The process of denitrification is

Likens and Bormann found that over 90% of the nutrients in the Hubbard Brook Experimental Forest were in the soil organic matter.

The end product of biological nitrogen fixation is

Clearcutting at Hubbard Brook Experimental Forest sharply

In aquatic ecosystems,leaves with high lignin content decompose

Pocket gophers change the nitrogen cycle in prairies because they

"Nitrogen fixation" refers to the conversion of

In stream ecosystems,nutrient retentiveness is

The rate of decomposition of leaf litter in woodlands can be strongly influenced by

Which of the following is NOT an assumption of the t-test?

Fungi and bacteria release nitrogen stored in dead tissue through a decomposition process called

The major pool of nitrogen in the atmosphere is the direct source of nitrogen for most organisms.

Phosphorus is an important constituent of

Which of the following are nitrogen fixing organisms?

The release of nutrients from organic material in inorganic form is called _____________.

Spiraling length of nutrients in streams can be calculated as S = VT.In this equation,

Nitrogen enrichment of ecosystems by human activity is largely driven by

Introduction to Ecology: Historical Foundations and Developing Frontiers

Life on Land

Life in Water

Population Genetics and Natural Selection

Temperature Relations

Water Relations

Energy and Nutrient Relations

Social Relations

Population Distribution and Abundance

Population Dynamics

Population Growth

Life Histories

Competition

Exploitative Interactions: Predation, herbivory, parasitism, and Disease

Mutualism

Species Abundance and Diversity

Species Interactions and Community Structure

Primary Production and Energy Flow

Succession and Stability

Landscape Ecology

Geographic Ecology

Global Ecology

Filters

The "denitrification" reaction converts nitrate (NO₃^-)to nitrogen gas (N₂)under aerobic conditions.

The release of ammonium (NH₄⁺)from decaying organic material is called ____________.