Page 1 of 13
ENVS 1126 LSU EXAM 2 (AIXIN HOU) EXAM QUESTIONS
WITH CORRECT VERIFIED ANSWERS GRADED TO PASS.
The current world population is approximately ______, and at present, we expect there to be about _______
people on earth when the population stabilizes in about 60 years.
8 billion; 10 billion
The amount of biomass on successive trophic levels in a food chain forms a pyramid in which the biomass
on trophic level N+1 is only 20% of the biomass on trophic level N. Pollutant X is transferred up the food
chain from one trophic level to the next with an efficiency of 80%. If the concentration of X on trophic
level 2 is 4 ppm, what would you expect the concentration of X to be on trophic level 4?
64 ppm
The Industrial Revolution has led to an increased reliance on fossil fuels to
power farm machinery and to produce fertilizers and pesticides.
The location of deserts in the northern and southern regions of Africa are best explained by understanding
convective air movement in Hadley cells
The planting of strips of trees and shrubs along the edges of plowed fields is used to
decrease wind erosion
The process by which water vapor passes through stomata from plants to the atmosphere is called
transpiration
The very deep roots of many prairie plants that have decomposed over thousands of years have contributed
to the high fertility of the
A horizon of mollisols
Using the IPAT formula, which of the following would most likely reduce the environmental impact of a
society?
a. construction of industrial plants by wealthy nations to draw on cheaper labor
b. the discovery of large reserves of fossil fuels within a nation's borders
c. greater use of birth control by most members of a society
d. increased use of electricity and natural gas by most members of a society
greater use of birth control by most members of a society
water evaporates because
kinetic energy increases enough to allow water molecules to break away from each other.
What factor is a threat to both coastal marshes and inland wetlands?
hydrology changes
, Page 2 of 13
What is the primary cause of land loss in Louisiana?
subsidence
What is the single largest use for freshwater by humans in the world?
agriculture
When can a demographic transition lead to problems?
when decreased fertility lags behind decreased deaths
Which of the following about Bt crops is true?
a. They produce chemicals that are similar to insect hormones, interrupting pest metamorphosis.
b. They produce chemicals that are similar to insect pheromones, interrupting pest mating cycles.
c. They produce chemicals that interfere with the molting of insect pests.
d. They incorporate the gene for producing a potent bacterially produced insecticide.
They incorporate the gene for producing a potent bacterially produced insecticide.
Which of the following best describes mycorrhizae?
a. Important soil millipedes that increase aeration of topsoil
b. Symbiotic fungi that increase soil nutrient uptake in plant roots
c. Common in soils that lack a functional humus
d. Pathogenic soil bacteria and fungi that destroy plant roots
Symbiotic fungi that increase soil nutrient uptake in plant roots
Which of the following decrease fertility rates?
a. All of the above
b. Reduced child mortality
c. Retirement security in old age
d. Sending girls to school
e. Access to contraception
a. ((All of the above))
b. Reduced child mortality
c. Retirement security in old age
d. Sending girls to school
e. Access to contraception
A declining dependency ratio
ENVS 1126 LSU EXAM 2 (AIXIN HOU) EXAM QUESTIONS
WITH CORRECT VERIFIED ANSWERS GRADED TO PASS.
The current world population is approximately ______, and at present, we expect there to be about _______
people on earth when the population stabilizes in about 60 years.
8 billion; 10 billion
The amount of biomass on successive trophic levels in a food chain forms a pyramid in which the biomass
on trophic level N+1 is only 20% of the biomass on trophic level N. Pollutant X is transferred up the food
chain from one trophic level to the next with an efficiency of 80%. If the concentration of X on trophic
level 2 is 4 ppm, what would you expect the concentration of X to be on trophic level 4?
64 ppm
The Industrial Revolution has led to an increased reliance on fossil fuels to
power farm machinery and to produce fertilizers and pesticides.
The location of deserts in the northern and southern regions of Africa are best explained by understanding
convective air movement in Hadley cells
The planting of strips of trees and shrubs along the edges of plowed fields is used to
decrease wind erosion
The process by which water vapor passes through stomata from plants to the atmosphere is called
transpiration
The very deep roots of many prairie plants that have decomposed over thousands of years have contributed
to the high fertility of the
A horizon of mollisols
Using the IPAT formula, which of the following would most likely reduce the environmental impact of a
society?
a. construction of industrial plants by wealthy nations to draw on cheaper labor
b. the discovery of large reserves of fossil fuels within a nation's borders
c. greater use of birth control by most members of a society
d. increased use of electricity and natural gas by most members of a society
greater use of birth control by most members of a society
water evaporates because
kinetic energy increases enough to allow water molecules to break away from each other.
What factor is a threat to both coastal marshes and inland wetlands?
hydrology changes
, Page 2 of 13
What is the primary cause of land loss in Louisiana?
subsidence
What is the single largest use for freshwater by humans in the world?
agriculture
When can a demographic transition lead to problems?
when decreased fertility lags behind decreased deaths
Which of the following about Bt crops is true?
a. They produce chemicals that are similar to insect hormones, interrupting pest metamorphosis.
b. They produce chemicals that are similar to insect pheromones, interrupting pest mating cycles.
c. They produce chemicals that interfere with the molting of insect pests.
d. They incorporate the gene for producing a potent bacterially produced insecticide.
They incorporate the gene for producing a potent bacterially produced insecticide.
Which of the following best describes mycorrhizae?
a. Important soil millipedes that increase aeration of topsoil
b. Symbiotic fungi that increase soil nutrient uptake in plant roots
c. Common in soils that lack a functional humus
d. Pathogenic soil bacteria and fungi that destroy plant roots
Symbiotic fungi that increase soil nutrient uptake in plant roots
Which of the following decrease fertility rates?
a. All of the above
b. Reduced child mortality
c. Retirement security in old age
d. Sending girls to school
e. Access to contraception
a. ((All of the above))
b. Reduced child mortality
c. Retirement security in old age
d. Sending girls to school
e. Access to contraception
A declining dependency ratio
