Question 1

Explain the difference between primary production and secondary production. How is secondary production affected by primary production?

Accepted Answer

Primary production refers to the process by which autotrophic organisms, such as plants and algae, convert sunlight into chemical energy through photosynthesis. This energy is then used to produce organic compounds, which form the base of the food chain and provide energy for all other organisms in the ecosystem.

Secondary production, on the other hand, refers to the process by which heterotrophic organisms, such as herbivores and carnivores, consume and digest the organic compounds produced by primary producers. This energy is then used for growth, reproduction, and maintenance of the organism.

The relationship between primary and secondary production is crucial for the functioning of ecosystems. The amount of energy and biomass available for secondary production is directly influenced by the amount of primary production in an ecosystem. In other words, the more energy and biomass that is produced by primary producers, the more energy and biomass is available for consumption by herbivores and subsequently by carnivores. Therefore, an increase in primary production can lead to an increase in secondary production, and vice versa.

Additionally, the quality and quantity of primary production can also affect the efficiency of secondary production. For example, if primary producers are nutrient-limited or if their biomass is difficult to access, it can limit the amount of energy available for consumption by herbivores and ultimately affect the growth and reproduction of higher trophic levels.

In summary, primary production and secondary production are interconnected processes that are essential for the functioning of ecosystems. The amount and quality of primary production directly influence the amount and efficiency of secondary production, ultimately shaping the structure and dynamics of ecological communities.

Question 2

In plants, low water availability favours the allocation of energy to the roots.

Accepted Answer

A) True 
 B)False  True

Question 3

Compare and contrast allochthonous and autochthonous functions within an ecosystem.

Accepted Answer

Both refer to the incorporation of energy and matter into an ecosystem. Allochthonous means from outside the ecosystem, and autochthonous means from within the ecosystem. Auto is via primary production where the producers within the ecosystem sequester the energy and matter to be transferred through the trophic levels of that system. Alternatively, carbon and energy from primary productivity can be brought in from another environment. This is usually from terrestrial to water in the form of leaf litter, but sometimes can go the opposite way such as when a bear captures a fish and drags it on to land, pulling resources from the water environment and bringing them into the terrestrial one.

Question 4

Aquatic ecosystems dominated by phytoplankton have ________ rates of herbivory than those in which vascular plants dominate.

Accepted Answer

A) lower 
B) higher 
C) equal 
D) more variable 
A) lower 
B) higher 
C) equal 
D) more variable

Question 5

Secondary production in an ecosystem is always less than primary production.

Accepted Answer

A) True 
 B)False

Question 6

The amount of energy within a food chain is greatest at the trophic level of

Accepted Answer

A) producers. 
B) herbivores. 
C) primary carnivores. 
D) secondary carnivores. 
A) producers. 
B) herbivores. 
C) primary carnivores. 
D) secondary carnivores.

Question 7

Describe the effects of temperature, moisture, length of photosynthetic period, and nutrient availability on net primary productivity in terrestrial ecosystems.

Accepted Answer

Temperature, moisture, length of photosy

Question 8

Low moisture conditions favour allocation by a plant to

Accepted Answer

A) leaves. 
B) stems. 
C) roots. 
D) flowers. 
A) leaves. 
B) stems. 
C) roots. 
D) flowers.

Question 9

In the photic zone, the major limitation on primary productivity is low

Accepted Answer

A) light. 
B) nutrient content. 
C) salinity. 
D) temperature. 
A) light. 
B) nutrient content. 
C) salinity. 
D) temperature.

Question 10

Wealthy nations typically have lower rates of human appropriation of net primary productivity (HANPP)than developing nations.

Accepted Answer

A) True 
 B)False

Question 11

In a body of water, the depth at which the availability of light is such that the rate of photosynthesis equals the rate of respiration is called the ________ depth.

Accepted Answer

The answer of In a body of water, the depth...

Question 12

The ________ law of thermodynamics states that energy is neither created nor destroyed.

Accepted Answer

The answer of The ________ law of thermodynamics states that...

Question 13

Primary productivity in forests often increases during the early stages of stand development, and then decreases again as the forest ages and standing biomass increases.

Accepted Answer

A) True 
 B)False

Question 14

Consumption efficiency is the ratio of ingestion to production.

Accepted Answer

A) True 
 B)False

Question 15

The rate of energy storage as organic matter after respiration is called ________ primary productivity.

Accepted Answer

The answer of The rate of energy storage as organic...

Question 16

The amount of accumulated organic matter found in an area at a given time is the ________ crop biomass.

Accepted Answer

The answer of The amount of accumulated organic matter found...

Question 17

In a grazing food chain, energy flow is unidirectional, whereas in a detrital food chain, energy is recycled.

Accepted Answer

A) True 
 B)False

Question 18

In most ecosystems, the biomass of carnivores is greater than the biomass of producers.

Accepted Answer

A) True 
 B)False

Question 19

In a temperate rain forest, primary productivity remains relatively constant.

Accepted Answer

A) True 
 B)False

Question 20

How are NPP and biomass different?

Accepted Answer

NPP (net primary pro

Exam 20: Ecosystem Energetic

Explain the difference between primary production and secondary production. How is secondary production affected by primary production?

In plants, low water availability favours the allocation of energy to the roots.

Compare and contrast allochthonous and autochthonous functions within an ecosystem.

Aquatic ecosystems dominated by phytoplankton have ________ rates of herbivory than those in which vascular plants dominate.

Secondary production in an ecosystem is always less than primary production.

The amount of energy within a food chain is greatest at the trophic level of

Describe the effects of temperature, moisture, length of photosynthetic period, and nutrient availability on net primary productivity in terrestrial ecosystems.

Low moisture conditions favour allocation by a plant to

In the photic zone, the major limitation on primary productivity is low

Wealthy nations typically have lower rates of human appropriation of net primary productivity (HANPP)than developing nations.

In a body of water, the depth at which the availability of light is such that the rate of photosynthesis equals the rate of respiration is called the ________ depth.

The ________ law of thermodynamics states that energy is neither created nor destroyed.

Primary productivity in forests often increases during the early stages of stand development, and then decreases again as the forest ages and standing biomass increases.

Consumption efficiency is the ratio of ingestion to production.

The rate of energy storage as organic matter after respiration is called ________ primary productivity.

The amount of accumulated organic matter found in an area at a given time is the ________ crop biomass.

In a grazing food chain, energy flow is unidirectional, whereas in a detrital food chain, energy is recycled.

In most ecosystems, the biomass of carnivores is greater than the biomass of producers.

In a temperate rain forest, primary productivity remains relatively constant.

How are NPP and biomass different?

The Nature of Ecology

Climate

The Aquatic Environment

The Terrestrial Environment

Ecological Genetics: Adaptation and Natural Selection

Plant Adaptations to the Environment

Animal Adaptations to the Environment

Life History Patterns

Properties of Populations

Population Growth

Intraspecific Population Regulation

Metapopulations

Interspecific Competition

Predation

Parasitism and Mutualism

Community Structure

Community Dynamics

Landscape Ecology

Systems Ecology

Decomposition and Nutrient Cycling

Biogeochemical Cycles

Terrestrial Ecosystems

Aquatic Ecosystems

Coastal and Wetland Ecosystems

Population Growth, Resource Use, and Sustainability

Conservation Ecology

Global Climate Change

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