Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

3.5 Energy Transfers Between Organisms > Nutrient Cycles > Flashcards

Nutrient Cycles Flashcards

1
Q

what species are saprobionts?

A

all fungi and some bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

how do saprobionts feed on dead or decaying matter?

A

secrete enzymes onto matter to digest it and absorbing the products of digesting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

4 enzymes used by saprobionts

A
  1. proteases
  2. lipases
  3. amylases
  4. cellulases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

3 molecules nitrogen is needed for

A
  1. nucleics acids
  2. a.a - proteins
  3. ATP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

4 chemicals of the nitrogen cycle

A
  1. N2 – nitrogen gas
  2. NH3 – ammonia (NH4+ – ammonium ions)
  3. NO2- – nitrite
  4. NO3- – nitrate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what form of N do plants in acidic soils absorb?

A

nitrates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what form of N do plants absorb in alkaline soils?

A

ammonium ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

why is N2 unavailable to majority of species?

A

it is inert due to a triple bond, therefore it is really stable and its bond can’t be broken

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

nitrogen fixing (bacteria, N conversion and respiration)?

A
  • nitrogen-fixing bacteria
  • N2 reduced to NH3
  • aerobic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

ammonification (bacteria, N conversion and respiration)?

A
  • saprobionts
  • amino acids to NH3
  • aerobic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

nitrificatioin (bacteria, N conversion and respiration)?

A
  • nitrifying bacteria
  • NH3 oxidised to NO2- and NO2- oxidised to NO3-
  • aerobic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

denitrification (bacteria, N conversion and respiration)?

A
  • denitrifying bacteria
  • NO3- reduced to N2
  • anaerobic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

are leguminous plants more competitive in N-rich or N-poor soils?

A

N-poor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what 3 molecules use phosphorous in their synthesis?

A
  1. ATP
  2. nucleic acids
  3. phospholipids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the process o phosphate ions going from oceans to rocks?

A

sedimentationi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how are phosphate ions taken up into plants?

A

absorbed by active transport

17
Q

what are mycorrhizae?

A

fungi which have a mutualistic reationship with plants, attached to their roots

18
Q

how do plants benefit from mycorrhizae?

A

can absorb more water and mineral ions

19
Q

how do mycorrhizae benefit from plants?

A

receive carbon compounds

20
Q

how do mycorrhizae expand absorption of plants?

A

increase SA and rage for absorption

21
Q

how do mycorrhizae increase absorption of phosphorus by plants?

A

hyphae can reach past pore zones created by plants taking up phosphorus

22
Q

hyphae

A

branching filaments of fungi

23
Q

how do mycorrhizae enhance plant disease resistance?

A

improves drought, cold, heavy metal metal pollution resistance

24
Q

how do mycorrhizae reduce soil erosion and stimulate microbial activity?

A

aggregate soil and release ‘auxin’ chemical which stimulates microbe activity and increases foil fertillity

25
Q

what is the main reason fertilisers are used?

A

crops take mineral ions from the soil and then are harvested, so ions are not released back into the soil.

26
Q

3 sources of natural fertilisers

A
  1. farm animals
  2. dead animals
  3. dead fish
27
Q

2 benefits of organic fertilisers

A
  1. contributes to soil structure and binds it
  2. releases ions slower due to saprobionts so less likely to leach
28
Q

what are artificial fertilisers made of?

A

concentrated mineral ions, usually N,P,K

29
Q

2 benefits of inorganic fertilisers

A
  1. smaller volumes can be applied
  2. can blend in known compositions specific to that crop
30
Q

leaching

A

process where mineral ions are dissolved in rainwater and carried into water bodies

31
Q

2 advantages of using fertilisers

A
  1. replace mineral ions removed in harvest so create better soil quality
  2. increase crop productivity so can grow taller crops and larger leaves so increase light absorption, increasing Ps, increasing GPP, increasing NPP
32
Q

3 disadvantages of using fertilisers

A
  1. reduce species diversity as specific crops will outcompete those that don’t benefit from the fertilisers
  2. leaching into water table and can enter water bodies
  3. eutrophication, resulting in an algal bloom
33
Q

eutrophication

A

a sudden increase in mineral ions in water bodies resulting in algal bloom

34
Q

what happens if eutrophication occurs?

A
  • algal bllom occurs, preventing light energy penetrating through water so lower plants can’t Ps so die
  • intraspecific competition b/w algae so algal death occurs
  • D.O.M. increases so theres and increase in saprobiont population so increased demand for O2 in water so less O2 available for aerobic invertebrates

3.5 Energy Transfers Between Organisms (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions