Question 1

Use the following figure to answer the questions below.
  
-On the diagram of the nitrogen cycle, which number represents nitrogen-fixing bacteria?

Accepted Answer

A) 5 
B) 6 
C) 7 
A) 5 
B) 6 
C) 7 A

Question 2

Aquatic ecosystems are least likely to be limited by which of the following nutrients?

Accepted Answer

A) nitrogen 
B) carbon 
C) phosphorus 
D) iron 
E) zinc 
A) nitrogen 
B) carbon 
C) phosphorus 
D) iron 
E) zinc B

Question 3

How is net ecosystem production (NEP)typically estimated in ecosystems?

Accepted Answer

A) the ratio of producers to consumers 
B) the amount of heat energy released by the ecosystem 
C) the net flux of CO₂ or O₂ in or out of an ecosystem 
D) the rate of decomposition by detrivores 
E) the annual total of incoming solar radiation per unit of area 
A) the ratio of producers to consumers 
B) the amount of heat energy released by the ecosystem 
C) the net flux of CO₂ or O₂ in or out of an ecosystem 
D) the rate of decomposition by detrivores 
E) the annual total of incoming solar radiation per unit of area C

Question 4

Secondary consumers that can eat only primary consumers receive what percentage of the energy fixed by primary producers in a typical field ecosystem?

Accepted Answer

A) 0.1% 
B) 1% 
C) 10% 
D) 20% 
E) 80% 
A) 0.1% 
B) 1% 
C) 10% 
D) 20% 
E) 80%

Question 5

Gross primary production

Accepted Answer

A) is equal to NPP - respiration of autotrophs. 
B) is about half of NPP. 
C) is the total biomass of all photosynthetic autotrophs. 
D) is the total energy from light converted to chemical energy of organic molecules per unit time. 
E) is not as important as net primary production. 
A) is equal to NPP - respiration of autotrophs. 
B) is about half of NPP. 
C) is the total biomass of all photosynthetic autotrophs. 
D) is the total energy from light converted to chemical energy of organic molecules per unit time. 
E) is not as important as net primary production.

Question 6

Which of these ecosystems has the lowest net primary production per square metre?

Accepted Answer

A) a salt marsh 
B) an open ocean 
C) a coral reef 
D) a grassland 
E) a tropical rain forest 
A) a salt marsh 
B) an open ocean 
C) a coral reef 
D) a grassland 
E) a tropical rain forest

Question 7

If you applied a fungicide to a cornfield, what would you expect to happen to the rate of decomposition and net ecosystem production (NEP)?

Accepted Answer

A) Both decomposition rate and NEP would decrease. 
B) Both decomposition rate and NEP would increase. 
C) Neither would change. 
D) Decomposition rate would increase and NEP would decrease. 
E) Decomposition rate would decrease and NEP would increase. 
A) Both decomposition rate and NEP would decrease. 
B) Both decomposition rate and NEP would increase. 
C) Neither would change. 
D) Decomposition rate would increase and NEP would decrease. 
E) Decomposition rate would decrease and NEP would increase.

Question 8

What is the primary limiting factor for aquatic productivity?

Accepted Answer

A) pressure 
B) lack of nutrients 
C) light availability 
D) herbivores 
E) competition 
A) pressure 
B) lack of nutrients 
C) light availability 
D) herbivores 
E) competition

Question 9

The following questions refer to the description below.
Fynbos are endemic shrubs found in the Cape province of South Africa. A small botanical region known as the Cape Floral Kingdom, is one of the richest areas in the world in terms of plant diversity. Fynbos shrubs, readily recognized by their small, hard, tough, leathery leaves, are well adapted to summer droughts, nutrient-poor soils, and periodic fires. The fynbos shrub community plays a key role in maintaining a regional supply of water. In recent decades, exotic plant species, such as acacia trees from Australia and pine trees from Europe, have been introduced to South Africa and have invaded the fynbos. Researchers are now observing that stream flow from fynbos watersheds is inversely proportional to plant biomass and natural fire cycles have changed.
-Speculate on the most likely reasons why exotic/invasive trees are disrupting the natural ecological functions of the fynbos shrub community. 1. Invasive tree species likely grow larger and faster than the shrubs and can increase the intensity and severity of fires, harming the native vegetation.
2. Invasive tree species require/utilize more water than native vegetation, decreasing stream flow.
3. Invasive trees are bigger than the native shrubs and prevent natural fires.
4. Invasive trees transpire less than the native fynbos, disrupting the hydrological cycle of the region.
5. The invasive species have a different root system and expose the area to soil erosion.

Accepted Answer

A) 1 and 2 
B) 1 and 3 
C) 1 and 4 
D) 3 and 5 
E) 4 and 5 
A) 1 and 2 
B) 1 and 3 
C) 1 and 4 
D) 3 and 5 
E) 4 and 5

Question 10

As big as it is, the ocean is nutrient-limited. If you wanted to investigate this, one reasonable approach would be to

Accepted Answer

A) follow whale migrations in order to determine where most nutrients are located. 
B) observe Antarctic Ocean productivity from year to year to see if it changes. 
C) experimentally enrich some areas of the ocean and compare their productivity to that of untreated areas. 
D) compare nutrient concentrations between the photic zone and the benthic zone in various marine locations. 
E) contrast nutrient uptake by autotrophs in marine locations that are different temperatures. 
A) follow whale migrations in order to determine where most nutrients are located. 
B) observe Antarctic Ocean productivity from year to year to see if it changes. 
C) experimentally enrich some areas of the ocean and compare their productivity to that of untreated areas. 
D) compare nutrient concentrations between the photic zone and the benthic zone in various marine locations. 
E) contrast nutrient uptake by autotrophs in marine locations that are different temperatures.

Question 11

The rate at which nutrients move through an ecosystem is most often limited by

Accepted Answer

A) decomposition rate. 
B) primary production. 
C) density of primary consumers. 
D) density of secondary consumers. 
E) density of tertiary consumers. 
A) decomposition rate. 
B) primary production. 
C) density of primary consumers. 
D) density of secondary consumers. 
E) density of tertiary consumers.

Question 12

What is secondary production?

Accepted Answer

A) energy converted by secondary consumers from primary consumers 
B) solar energy that is converted to chemical energy by photosynthesis 
C) food that is converted to new biomass by consumers 
D) energy that is not used by consumers for growth and reproduction 
E) growth that takes place during the second year of life in consumers 
A) energy converted by secondary consumers from primary consumers 
B) solar energy that is converted to chemical energy by photosynthesis 
C) food that is converted to new biomass by consumers 
D) energy that is not used by consumers for growth and reproduction 
E) growth that takes place during the second year of life in consumers

Question 13

Decomposers obtain energy from

Accepted Answer

A) live organic material 
B) detritus 
C) fungi 
D) other heterotrophs 
E) bacteria 
A) live organic material 
B) detritus 
C) fungi 
D) other heterotrophs 
E) bacteria

Question 14

Subtraction of which of the following will convert gross primary productivity into net primary productivity?

Accepted Answer

A) the energy contained in the standing crop 
B) the energy used by heterotrophs in respiration 
C) the energy used by autotrophs in respiration 
D) the energy fixed by photosynthesis 
E) all solar energy 
A) the energy contained in the standing crop 
B) the energy used by heterotrophs in respiration 
C) the energy used by autotrophs in respiration 
D) the energy fixed by photosynthesis 
E) all solar energy

Question 15

A 3-hectare lake in the American Midwest suddenly has succumbed to an algal bloom. What is the likely cause of eutrophication in freshwater ecosystems, such as this one?

Accepted Answer

A) increased solar radiation 
B) introduction of non-native tertiary consumer fish 
C) nutrient runoff 
D) accidental introduction of a prolific culture of algae 
E) iron dust blowing into the lake 
A) increased solar radiation 
B) introduction of non-native tertiary consumer fish 
C) nutrient runoff 
D) accidental introduction of a prolific culture of algae 
E) iron dust blowing into the lake

Question 16

Why do logged tropical rain forest soils typically have nutrient-poor soils?

Accepted Answer

A) Tropical bedrock contains little phosphorous. 
B) Logging results in soil temperatures that are lethal to nitrogen-fixing bacteria. 
C) Most of the nutrients in the ecosystem are removed in the harvested timber. 
D) The cation exchange capacity of the soil is reversed as a result of logging. 
E) Nutrients evaporate easily into the atmosphere in the post-logged forest. 
A) Tropical bedrock contains little phosphorous. 
B) Logging results in soil temperatures that are lethal to nitrogen-fixing bacteria. 
C) Most of the nutrients in the ecosystem are removed in the harvested timber. 
D) The cation exchange capacity of the soil is reversed as a result of logging. 
E) Nutrients evaporate easily into the atmosphere in the post-logged forest.

Question 17

Which of the following is an example of a local biogeochemical cycle?

Accepted Answer

A) O₂ released by oak trees in a forest 
B) CO₂ absorbed by phytoplankton in the open ocean 
C) excess NO₃⁻ converted to N₂ by denitrifying soil bacteria 
D) phosphorous being absorbed from the soil by a corn plant 
E) organic carbon remains of a leaf being converted to CO₂ by a fungus 
A) O₂ released by oak trees in a forest 
B) CO₂ absorbed by phytoplankton in the open ocean 
C) excess NO₃⁻ converted to N₂ by denitrifying soil bacteria 
D) phosphorous being absorbed from the soil by a corn plant 
E) organic carbon remains of a leaf being converted to CO₂ by a fungus

Question 18

Aquatic primary productivity is most limited by which of the following?

Accepted Answer

A) light and nutrient availability 
B) predation by primary consumers 
C) increased pressure with depth 
D) pollution 
E) temperature 
A) light and nutrient availability 
B) predation by primary consumers 
C) increased pressure with depth 
D) pollution 
E) temperature

Question 19

Use the following food web to answer the questions below.
   
Diagram of a food web (arrows represent energy flow and letters represent species)
-If the figure above represents a terrestrial food web, the combined biomass of C + D would probably be

Accepted Answer

A) greater than the biomass of A. 
B) less than the biomass of H. 
C) greater than the biomass of B. 
D) less than the biomass of A + B. 
E) less than the biomass of E. 
A) greater than the biomass of A. 
B) less than the biomass of H. 
C) greater than the biomass of B. 
D) less than the biomass of A + B. 
E) less than the biomass of E.

Question 20

Which of the following organisms is incorrectly paired with its trophic level?

Accepted Answer

A) cyanobacterium-primary producer 
B) grasshopper-primary consumer 
C) zooplankton-primary producer 
D) eagle-tertiary consumer 
E) fungus-detritivore 
A) cyanobacterium-primary producer 
B) grasshopper-primary consumer 
C) zooplankton-primary producer 
D) eagle-tertiary consumer 
E) fungus-detritivore

Exam 55: Ecosystems and Restoration Ecology

Use the following figure to answer the questions below. -On the diagram of the nitrogen cycle, which number represents nitrogen-fixing bacteria?

Aquatic ecosystems are least likely to be limited by which of the following nutrients?

How is net ecosystem production (NEP)typically estimated in ecosystems?

Secondary consumers that can eat only primary consumers receive what percentage of the energy fixed by primary producers in a typical field ecosystem?

Gross primary production

Which of these ecosystems has the lowest net primary production per square metre?

If you applied a fungicide to a cornfield, what would you expect to happen to the rate of decomposition and net ecosystem production (NEP)?

What is the primary limiting factor for aquatic productivity?

As big as it is, the ocean is nutrient-limited. If you wanted to investigate this, one reasonable approach would be to

The rate at which nutrients move through an ecosystem is most often limited by

What is secondary production?

Decomposers obtain energy from

Subtraction of which of the following will convert gross primary productivity into net primary productivity?

A 3-hectare lake in the American Midwest suddenly has succumbed to an algal bloom. What is the likely cause of eutrophication in freshwater ecosystems, such as this one?

Why do logged tropical rain forest soils typically have nutrient-poor soils?

Which of the following is an example of a local biogeochemical cycle?

Aquatic primary productivity is most limited by which of the following?

Use the following food web to answer the questions below. Diagram of a food web (arrows represent energy flow and letters represent species) -If the figure above represents a terrestrial food web, the combined biomass of C + D would probably be

Which of the following organisms is incorrectly paired with its trophic level?

Introduction: Evolution and Themes of Biology

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

From Gene to Protein

Regulation of Gene Expression

Viruses

Dna Tools and Biotechnology

Genomes and Their Evolution

Descent With Modification: a Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity Ii: the Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Plant Structure, Growth, and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signalling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behaviour

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Conservation Biology and Global Change

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