LO14

Question 1

What is the general ecosystem definition?

Answer 1

a complex network, or interconnected system.

Question 2

whats is the biology definition of an ecosystem?

Answer 2

a community of interacting organisms and their physical environment.

Question 3

What is the first law of thermodynamics?

Answer 3

Energy cannot be created or destroyed, only transformed.

Question 4

Energy enters an ecosystem as……., is transformed, and is lost as…….

Answer 4

Energy enters an ecosystem as solar radiation, is transformed, and is lost as heat.

Question 5

What is the second law of thermodynamics?

Answer 5

“With each energy conversion, a part of the energy becomes unable to do work” “Energy conversions are inefficient”

Question 6

What is the law of conversion of mass?

Answer 6

Matter cannot be created or destroyed

• For Chemistry
• For physiology

Question 7

What are two key emergent properties at the ecosystem level?

Answer 7

Energy flow and Chemical flow

Question 8

Energy and nutrients pass from …………. (autotrophs) to……………….. (herbivores) to ………………. (carnivores) to …………………. (carnivores that feed on other carnivores)

Answer 8

Energy and nutrients pass from primary producers (autotrophs) to primary consumers (herbivores) to secondary consumers (carnivores) to tertiary consumers (carnivores that feed on other carnivores)

Question 9

………………., or …………….., are consumers that derive their energy from ………………, nonliving organic matter

Answer 9

Detritivores, or decomposers, are consumers that derive their energy from detritus, nonliving organic matter

Question 10

………. and ………….. are important detritivores

Answer 10

Prokaryotes and fungi are important detritivores (eat detritus/dead things)

Question 11

……………….. connects all trophic levels

Answer 11

Decomposition connects all trophic levels

Question 12

In most ecosystems, ………………… is the amount of light energy converted to chemical energy by photo autotrophs during a given time period

Answer 12

In most ecosystems, primary production is the amount of light energy converted to chemical energy by photo autotrophs during a given time period

Question 13

In a few ecosystems, …………………….. are the primary producers, e.g. deep sea vent ecosystems

Answer 13

In a few ecosystems, chemoautotrophs are the primary producers, e.g. deep sea vent ecosystems

Question 14

Total primary production is known as the ecosystem’s ………………….

Answer 14

Total primary production is known as the ecosystem’s gross primary production (GPP)

Question 15

………… is measured as the conversion of ………. into ………………. through ………….. per unit time

Answer 15

GPP is measured as the conversion of solar energy into chemical energy through photosynthesis per unit time

Question 16

…………….. is GPP minus energy used by primary producers for ……………………

Answer 16

Net primary production (NPP) is GPP minus energy used by primary producers for respiration (autotrophic respiration)

Question 17

What is the equation for NPP

Answer 17

NPP = GPP – Ra

Question 18

……………………….is a measure of the total biomass accumulation during a given period

Answer 18

Net ecosystem production (NEP) is a measure of the total biomass accumulation during a given period

Question 19

…………… is gross primary production minus …………………, which is the total respiration of all organisms (producers and consumers) in an ecosystem

Answer 19

NEP is gross primary production minus ecosystem respiration (Reco), which is the total respiration of all organisms (producers and consumers) in an ecosystem

Question 20

How is NEP (net ecosystem production) estimated?

Answer 20

NEP (net ecosystem production) is estimated by measuring the measuring the net flux of CO2 in an ecosystem:

SPECIFIC EXAMPLES:
Photosynthesis: CO2 enters the ecosystem
Respiration: CO2 released from ecosystem

Question 21

…………………..of an ecosystem is the amount of chemical energy in food converted to new biomass during a given period of time

Answer 21

Secondary production of an ecosystem is the amount of chemical energy in food converted to new biomass during a given period of time

Question 22

An organism’s ………………………….. is the fraction of energy in assimilated food that is used for biomass production, i.e. the fraction that is NOT used

Answer 22

An organism’s production efficiency is the fraction of energy in assimilated food that is used for biomass production, i.e. the fraction that is NOT used

Question 23

………………………. is the percentage of production transferred from one trophic level to the next

Answer 23

Trophic efficiency is the percentage of production transferred from one trophic level to the next.

It is usually about 10%, with a range of 5% to 20%

Question 24

…………………… is multiplied over the length of a food chain:

What would be an example of this?

Answer 24

Trophic efficiency is multiplied over the length of a food chain:

Example:.approximately 0.1% of chemical energy fixed by photosynthesis reaches a tertiary consumer: 100%  10%  1%  0.1%

Question 25

A pyramid of .................represents the loss of energy with each transfer in a food chain

Answer 25

A pyramid of net production represents the loss of energy with each transfer in a food chain. (refer back to slide 19-20 for an image of pyramid)

Question 26

The ................. suggests that length is limited by inefficient energy transfer.

Answer 26

The energetic hypothesis suggests that length is limited by inefficient energy transfer. Each food chain in a food web is usually only a few links long.

Question 27

Life depends on ..............of chemical elements What are some examples of this?

Answer 27

Life depends on recycling of chemical elements Gaseous carbon, oxygen, sulfur, and nitrogen cycle globally Less mobile elements - phosphorus, potassium, and calcium - cycle locally

Question 28

In studying cycling of water, carbon and nitrogen, ecologists focus what four questions?

Answer 28

1) Each chemical’s biological importance 2) Forms in which each chemical is available or used by organisms 3) Major reservoirs for each chemical 4) Key processes driving movement of each chemical through its cycle

Question 29

Water moves by the processes of ..................................... through surface and groundwater.

Answer 29

Water moves by the processes of evaporation, transpiration, condensation, precipitation, and movement through surface and groundwater

Question 30

Photosynthetic organisms convert .................to ......................, those are used in turn by heterotrophs.

Answer 30

Photosynthetic organisms convert CO2 to organic molecules, those are used in turn by heterotrophs.

Question 31

Carbon reservoirs include ......................?

Answer 31

Carbon reservoirs include fossil fuels, soils and sediments, solutes in oceans, plant and animal biomass, the atmosphere, and sedimentary rocks

Question 32

CO2 is taken up and released through ...................and ......................; additionally, volcanoes, LULC change and the burning of fossil fuels contribute CO2 to the atmosphere

Answer 32

CO2 is taken up and released through photosynthesis and respiration; additionally, volcanoes, LULC change and the burning of fossil fuels contribute CO2 to the atmosphere

Question 33

The main reservoir of nitrogen is the ........................., though this nitrogen must be converted to .......................for uptake by plants, via nitrogen fixation by bacteria (Nitrogen Cycle)

Answer 33

The main reservoir of nitrogen is the atmosphere (N2), though this nitrogen must be converted to NH4+ or NO3– for uptake by plants, via nitrogen fixation by bacteria

Question 34

Organic nitrogen is decomposed to NH4+ by ........................, and NH4+ is decomposed to NO3– by ......................

Answer 34

Organic nitrogen is decomposed to NH4+ by ammonification, and NH4+ is decomposed to NO3– by nitrification

Question 35

........................... converts NO3– back to N2

Answer 35

Denitrification converts NO3– back to N2

Question 36

Nitrogen is a component of ...........................?

Answer 36

Nitrogen is a component of amino acids, proteins, and nucleic acids