Deck 20: Ecosystem Energetic

Question 1

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

Answer 1

first

Question 2

The ________ law of thermodynamics states that when energy is transferred or transformed, part of the energy assumes a form that cannot pass on any further.

Answer 2

second

Question 3

________ primary production is the total rate of photosynthesis, or energy assimilated by plants.

Answer 3

Gross

Question 4

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

Question 5

The amount of accumulated organic matter found in an area at a given time is referred to as

A)gross primary productivity.
B)net primary productivity.
C)secondary productivity.
D)standing crop biomass.

Question 6

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.

Question 7

________ efficiency is the ratio of assimilation to ingestion and is a measure of the efficiency with which a consumer extracts energy from food.

Question 8

How are NPP and biomass different?

Question 9

Net primary productivity refers to

A)the total rate of photosynthesis, or energy assimilated, by autotrophs.
B)the rate of energy storage as organic matter by autotrophs after respiration is deducted.
C)the amount of accumulated organic matter found in an area at a given time.
D)the production of new tissues and offspring by heterotrophs.

Question 10

For photosynthesis and productivity to occur, a plant must open its ________ to take in carbon dioxide.

Question 11

The net energy going into growth of new tissues and production of young in heterotrophs is called ________ production.

Question 12

________ efficiency is the ratio of productivity in a given trophic level to the productivity of the trophic level on which it feeds.

Question 13

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

Question 14

Energy is assimilated by plants through the process of

A)decomposition.
B)respiration.
C)photosynthesis.
D)regeneration.

Question 15

Within any ecosystem, there are two major food chains: the ________ food chain and the grazing food chain.

Question 16

Primary productivity is greatest under

A)low temperatures and moist conditions.
B)low temperatures and dry conditions.
C)high temperatures and moist conditions.
D)high temperatures and dry conditions.

Question 17

________ is the primary factor that limits productivity in aquatic ecosystems.

Question 18

According to the first law of thermodynamics

A)chemical reactions are exergonic.
B)entropy tends to increase.
C)potential energy tends to degrade into an unavailable form.
D)energy is neither created nor destroyed.

Question 19

________ net primary productivity is the ratio of net primary productivity to standing biomass.

Question 20

A(n)________ chemical reaction must absorb energy in order to proceed.

Question 21

An inverted biomass pyramid may exist in aquatic systems because

A)zooplankton are much larger than phytoplankton.
B)phytoplankton are heavily grazed and biomass can't accumulate.
C)more energy is inputted through allochthonous processes.
D)of none of the above. This cannot happen as it goes against the 2ⁿᵈ law of thermodynamics.

Question 22

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

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

Question 23

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

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

Question 24

Net primary productivity is greater in moist climates than in dry climates.

Question 25

Allochthonous carbon input is most commonly found in ________ ecosystems.

A)terrestrial
B)stream
C)desert
D)ocean

Question 26

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

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

Question 27

In most terrestrial and many aquatic ecosystems, the ________ food chain is the dominant pathway of energy flow.

A)detrital
B)grazing
C)consumer
D)heterotroph

Question 28

The first law of thermodynamics states that when energy is transformed or transferred, part of it assumes a form that cannot be passed on any further so that entropy increases.

Question 29

Which organism is most likely to have the highest assimilation efficiency?

A)an endothermic carnivore, such as a lion
B)an ectothermic carnivore, such as a snake
C)an endothermic herbivore, such as a deer
D)an ectothermic herbivore, such as a grasshopper

Question 30

Net primary productivity is greater in warm climates than in cold climates.

Question 31

Net primary productivity is greater in the open ocean than along the coast.

Question 32

Ecosystems have two major food chains

A)producers and consumers.
B)autotrophs and heterotrophs.
C)primary and secondary.
D)grazing and detrital.

Question 33

Energy from primary production that remains after respiration is called net primary production.

Question 34

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

Question 35

Secondary production is limited primarily by

A)primary production.
B)nutrient availability.
C)water availability.
D)light availability.

Question 36

When a chemical reaction results in the loss of energy from the system, the reaction is exergonic.

Question 37

Assimilation efficiency is

A)the proportion of energy ingested that is not lost to respiration.
B)the proportion of energy ingested that is assimilated.
C)the proportion of assimilated energy that is not lost as waste material.
D)the proportion of assimilated energy that goes to production.

Question 38

Low moisture conditions favour allocation by a plant to

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

Question 39

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

Question 40

When stomata are open, a plant is gaining CO₂ but losing water.

Question 41

Compare and contrast allochthonous and autochthonous functions within an ecosystem.

Question 42

Consumption efficiency is the ratio of ingestion to production.

Question 43

How do humans affect net primary productivity? Does the affluence of a society affect how humans appropriate net primary productivity?

Question 44

What are the two main food chains of ecosystems? Which is more dominant in terrestrial ecosystems and why?

Question 45

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

Question 46

Endotherms typically have a higher assimilation efficiency than ectotherms.

Question 47

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

Question 48

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.

Question 49

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

Question 50

Ecosystems have three major food chains: the autotrophs, the heterotrophs, and the decomposers.

Question 51

Production efficiency is the proportion of the energy ingested that is assimilated.

Question 52

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

Question 53

In terrestrial ecosystems, most of the primary production goes into the grazing food chain.

Question 54

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

Question 55

In terrestrial and shallow-water ecosystems, the grazing food chain is dominant over the detrital food chain.

Question 56

Explain why energy is lost as it is transferred from one trophic level to another. What are the effects of energy loss on the biomass of different trophic levels?

Question 57

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

Question 58

In stream and river ecosystems, the grazing food chain is of minor importance compared with the detrital food chain.

Question 59

Explain why primary productivity is typically higher in coastal areas of the ocean than far from shore in the open ocean.