Ch. 55

Question 1

Ecosystem

Answer 1

all the organisms living in an area as well as the abiotic factors with which they interact

Question 1

Microcosm

Answer 1

example a space under a fallen log

Question 2

Ecosystems include two processes

Answer 2

energy flow and chemical cycling

Question 3

Energy flow vs chemical cycle

Answer 3

energy flow through ecosystems
chemicals cycle within ecosystems

Question 4

First law of thermodynamics

Answer 4

energy cannot be created or destroyed, only transferred or transformed

Question 5

How do energy enter an ecosystem?

Answer 5

solar radiation

Question 6

second law of thermodynamics

Answer 6

every exchange of energy increases the entropy of the universe

Question 7

law of conservation of mass

Answer 7

matter cannot be created or destroyed

Question 8

Open systems

Answer 8

absorbing energy and mass and releasing heat and waste products

Question 9

Autotrophs

Answer 9

build molecules themselves using photosynthesis or chemosynthesis as an energy source to connect carbon together

Question 10

Heterotrophs

Answer 10

depend on biosynthetic output of other organisms

Question 11

How do energy and nutrients pass?

Answer 11

primary producers
primary consumers
secondary consumers
tertiary consumers

Question 12

Detritivores (decomposers)

Answer 12

heterotrophs that derive their energy from detritus (nonliving organic matter)

Question 13

Detritus

Answer 13

nonliving organic matter

Question 14

What are the main detritivores?

Answer 14

Prokaryotes and fungi

Question 15

Primary production

Answer 15

the amount of light energy converted to chemical bond energy by autotrophs during a given time period

Question 16

Gross primary production (GPP)

Answer 16

total primary production

Question 17

How is GPP measured?

Answer 17

conversion of energy from light to the chemical bond energy of organic molecules per unit time

Question 18

Net primary production (NPP)

Answer 18

GPP minus energy used by autotrophs for respiration (Ra)

Question 19

How is primary production expressed?

Answer 19

energy per unit area per unit time
biomass added per unit area per unit time

Question 20

What does NPP measure

Answer 20

amount of new biomass added in a given time period

Question 21

What are the most productive ecosystems?

Answer 21

tropical rain forests, estuaries, and coral reefs

Question 22

What ecosystems are relatively unproductive?

Answer 22

marine ecosystems
still contribute to NPP because of size

Question 23

What limits primary production?

Answer 23

light and nutrients

Question 24

Limiting nutrient

Answer 24

element that must be added for production to increase in an area

Question 25

What limits marine production?

Answer 25

nitrogen and phosphorous

Question 26

What contributes to regions of high primary production?

Answer 26

Upwelling of nutrients rich waters

Question 27

Eutrophication

Answer 27

excessive richness of nutrients in a body of water due to sewage runoff this promotes the growth of primary producers

Question 28

Effect of eutrophication

Answer 28

detritivores (eat dead organic material) use up dissolved oxygen which breaks down dead producers loss of oxygen leads to dead fish

Question 29

What happens in lakes?

Answer 29

phosphorous limits cyanobacterial growth more often than nitrogen

Question 30

What affects primary production?

Answer 30

temperature and moisture

Question 31

What can increase NPP (minus energy used by autotrophs)?

Answer 31

precipitation increase of temperature increase of solar energy

Question 32

Nitrogen

Answer 32

the most common limiting nutrient in terrestrial ecosystems

Question 33

Phosphorous

Answer 33

another limiting nutrient, especially in older soils

Question 34

What are some adaptations that help plants access limiting nutrients from soil?

Answer 34

plants form mutualisms with nitrogen fixing bacteria plants form mutualisms with mycorrhizal fungi

Question 35

Do plants release enzymes that increase the availability of limiting nutrients?

Answer 35

yes

Question 36

Secondary production

Answer 36

the production of biomass by heterotrophic consumers

Question 37

When a caterpillar feeds on a leaf, on about ____ of the leaf's energy is used for secondary production

Answer 37

1/6

Question 38

Efficiencies of birds and mammals?

Answer 38

1-3%

Question 39

Fishes production efficiencies

Answer 39

10%

Question 40

Insects and microorganisms efficiencies

Answer 40

40% or more

Question 41

Trophic efficiency

Answer 41

percentage of production transferred from one trophic level to the next (usually 10%)

Question 42

How much chemical energy fixed by photosynthesis reaches a tertiary consumer?

Answer 42

0.1%

Question 43

What does an energy pyramid represent?

Answer 43

loss of energy with each transfer in a food chain

Question 44

Biomass pyramid

Answer 44

dry mass of all organisms in one trophic level

Question 45

What ecosystems have inverted biomass pyramids because phytoplankton (producers) are consumed so quickly?

Answer 45

aquatic ecosystems

Question 46

Who plays a key role in chemical cycling?

Answer 46

decomposers

Question 47

What controls the rate of decomposition?

Answer 47

temperature, moisture, nutrient availability

Question 48

What is the result of rapid decomposition?

Answer 48

relatively low levels of nutrients in soil

Question 49

What ecosystems store large amount of undecomposed organic matter (decomposition rates are low)?

Answer 49

cold and wet ecosystems

Question 50

Biogeochemical cycles

Answer 50

nutrient cycles, involve both biotic and abiotic components

Question 51

Oceans contain how much of the biosphere's water?

Answer 51

97%

Question 52

How much of the biosphere's water is contained in glaciers and polar ice caps?

Answer 52

2%

Question 53

Lakes, rivers, and groundwater contain how much water?

Answer 53

1%

Question 54

What are the processes in which water moves by?

Answer 54

evaporation, transpiration, condensation, precipitation, and movement through surface and groundwater

Question 55

Carbon cycle

Answer 55

photosynthetic organisms convert CO2 to organic molecules that are consumed by heterotrophs

Question 56

What are carbon reservoirs?

Answer 56

fossil fuels soils and sediments solutes in the ocean plant and animal biomass atmosphere sedimentary rocks

Question 57

How is Co2 released?

Answer 57

photosynthesis and respiration volcanoes and burning of fossil fuels

Question 58

Nitrogen cycle

Answer 58

main reservoir of nitrogen is in the atmosphere (N2) nitrogen has to be coverted to NH4 or NO3 for uptake by plants nitrogen fixation by bacteria animals can only use organic nitrogen

Question 59

Ammonification

Answer 59

organic nitrogen is decomposed to NH4+

Question 60

Denitrification

Answer 60

converts NO3- to N2

Question 61

Phosphorous cycle

Answer 61

largest reservoirs are sedimentary rocks of marine origin, soil, the oceans, and organisms weathering of rocks releases phosphate into the soil and it reaches aquatic systems through leaching

Question 62

Phosphorous is a major part of?

Answer 62

nucleic acids, phospholipids, ATP

Question 63

Nitrogen is a component of?

Answer 63

amino acids, proteins, nucleic acids