Topic 29 Flashcards Preview

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Flashcards in Topic 29 Deck (59)
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1
Q

Ecosystems are considered to be..

A

open systems (closed systems have no inputs and outputs)

2
Q

Inputs

A

exchanges from surrounding environment into the ecosystem

3
Q

Outputs

A

exchanges from inside the ecosystem out to the surrounding environment

4
Q

Nutrients

A

typically recycled within the system

5
Q

Inputs and outputs of nutrients exist but they are..

A

predominantly cycles within an ecosystem

6
Q

Energy come from

A

the sun (input) and leaves the ecosystem as heat (output)

7
Q

Energy is an ecosystem exists in two forms

A
  • potential energy (stored)

- kinetic energy (expended)

8
Q

Sunlight is the ..

A

ultimate source of energy powering the biosphere

9
Q

All ecological process involve

A

transfer of energy

10
Q

All energy transfers are ..

A

subject to laws of thermodynamics

11
Q

Energy is not..

A

created or destroyEd. can change form or move.

12
Q

With every transfer some useful energy is..

A

lost

13
Q

1st law of thermodynamics

A

amount of energy is constant. energy cannot be created or destroyed.

14
Q

Example of 1st law

A

burning wood: potential energy (stored in molecular bond) to kinetic energy (released as heat)

15
Q

2nd law of thermodynamics

A

whenever energy is transformed, some energy become unavailable to further use.

16
Q

Example of 2nd law

A

burning fuel: kinetic energy dissipates as heat

17
Q

1st law and ecology

A

energy cannot be created or destroyed in ecosystem (constant) energy from sun is harvested by 1st producers and use to form chemical bonds in carbon based compounds. potential energy stored in these chemical bonds is transferred to consumer when they eat plants

18
Q

2nd law and ecology

A

energy becomes unavailable when transferred amount trophic levels through reeding relationships ..

19
Q

As energy is transferred form ne organisms to another a portion is ..

A

used (stored as energy in living tissues as organisms grows) but a large part dissipates as heat

20
Q

In closed systems over time the amount of energy in..

A

unusable forms increases unit no usable energy is available

21
Q

But ecosystems are open systems and ..

A

receive constant energy input from the sun and counteracts the issue

22
Q

Primary production

A

refers to the rate at which plant tissues (organic matter) is created during photosynthesis

23
Q

Plant species vary in their rates of photosynthesis or ..

A

efficiency to transform energy from sun to plant tissue

24
Q

Photosynthetic rates will be influence by..

A
  • Quantity of above(shoots & leaves) and below ground (roots) tissue
  • Leaf morphology (e.g. surface area)
  • Modified photosynthetic pathways to increase water-use efficiency (e.g. C4 & CAM plants)
  • Adaptations to low light (shade-tolerant) or high light (shade-intolerant)
25
Q

Secondary production

A

refers to the effieceny of consumers to transform energy consumed to growth and offspring

26
Q

The total energy consumed/ingested in the form of plant material flows through each individual consumer ..

A
  • a portion is assimilated though the gut wall
  • remainder is expelled from the body as waste
  • *finish notes on secondary here
27
Q

Production efficiency

A

the efficiency of consumer species to transform energy consumed into 2nd production = P/A (production/assimilation)

28
Q

General patterns for P/A

A

invertebrates&raquo_space; vertebrates

29
Q

Vertebrates

A
  • ectotherm .» endotherm. higher energy allocation to maintain constant body temp
  • carnivores&raquo_space; herbivores. harder to assimilate plant tissue
30
Q

P/A of all species at each trophic level will.

A

determine energy available for next higher trophic level

31
Q

General pattern of trophic efficiency

A

quantity of energy available for use by a trophic level decrease with each successive trophic level in the food chain due to production efficiencies (2nd law)

32
Q

Ecological rule

A

only 10% of the energy stores as biomass within given trophic level is converted to biomass as next higher trophic level (10% rule)

33
Q

Result of ecological rule

A

decrease in the biomass of organisms within each successive trophic level (pyramid of biomass)

34
Q

Primary productivity relies on

A

photosynthetic organisms taking up carbon and other minerals

35
Q

Living tissue can be consumed..

A

passing minerals, carbon and energy up the food chain. age die and decompose returning minerals tot he soil

36
Q

Some carbon is added to..

A

soil but most is release back tiny atmosphere

37
Q

Decomposers

A

recycle minerals back into their local ecosystems. essential function in all ecosystems

38
Q

Nutrient (calcium, nitrogen) source is

A

atmosphere or weathering of rocks and minerals

39
Q

Taken up by plants

A

move through food chain via feeding relationships

40
Q

Significant portion of nutrient in an ecosystem are..

A

stored in organic form within living tissue of plants and animals

41
Q

Most of essential nutrients are recycled within ecosystem by ..

A

decomposers = internal cycling

42
Q

Once living tissue dies, it falls into the soil or aquatic sediments in the form of..

A

dead organic mayor

43
Q

Decomposers breakdown the chemical bonds from during construction of plant and animal tissue and releases..

A

energy originally fixed by photosynthesis, converts organic compounds into inorganic compounds (mineralization) for use by plants

44
Q

Succession of species occurs until..

A

material is finally reduced completely to inorganic nutrients

45
Q

All organic matter does not..

A

decompose at the same rate

46
Q

Simple compounds result in

A

higher net energy gain. (=energy game - loss) to decomposers relative to complex compounds

47
Q

Simple carbohydrates are..

A

high quality- breaking chemical bonds yields much more energy than required to synthesize the enzyme to break them down

48
Q

Microbial decomposers (bacteria and fungi)

A

secrete enzymes into plant and animal tissues to breakdown the complex organic compounds. some products absorbed as food

49
Q

Detritivores

A

animals that feed on dead organic material and waste products (invertebrates) aid decomposition by fragmenting larger pieces

50
Q

More complex structure carbon based compounds..

A

(cellulose) are low quality and most costly to decompose

51
Q

Even more complex (lignins) are..

A

lower quality and weald no net energy gain

52
Q

Abiotic factors have direct influence on decomposition rates..

A

temp and moisture greatly influence microbial activity

53
Q

Cool, dry conditions reduce..

A

inhibit activity

54
Q

Warm moist conditions are optimal

A

conditions for activity

55
Q

Rates of internal cycling of nutrients depend directly on

A

rates of 2 processes: primary production and decomposition

56
Q

Primary production determines the rate of..

A

nutrient transfer from inorganic to organic form (nutrient uptake)

57
Q

Decomposition determines the rate of..

A

transformation of organic to inorganic form (mineralization)

58
Q

Reduced availability of inorganic nutrients in the soil will diretly

A

reduce photosynthesic rates and primary production

59
Q

Influences the input of dead organisms matter to the..

A

detrital food chain by reducing the total quantity of dead organic matter produced (feedback mechanisms in internal cycling of nutrients within an ecosystem)