Brainscape's Knowledge GenomeTM

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


See full index

A2 Biology - unit 4 > Unit 3.4.6 - Chemical Cycles > Flashcards

Unit 3.4.6 - Chemical Cycles Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What are the main too nutrients cycles?

A

Carbon and nitrogen

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

What does the carbon cycle show?

A

How carbon is transferred through the environment

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

What is decomposition?

A

When organic matter is broken down by microorganisms called decomposers

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

What is saprobiontic nutrition?

A

The way decomposers feed on dead organic matter

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

How do decomposers carry out saprobiontic nutrition?

A

They secrete enzymes onto the dead organic matter which breaks down the carbon compounds, they then absorb the digested nutrients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens if dead organic matter ends up in a place where there aren’t any decomposers?

A

The carbon compounds can be turned into fossil fuels over millions of year

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

What does the nitrogen cycle show?

A

How nitrogen is transferred through the environment

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

By which five things is nitrogen added to the soil?

A

Nitrogen fixation, lightning, fertilisers, ammonification and nitrification

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

What happens during nitrogen fixation?

A

Nitrogen reacts with hydrogen to form ammonia carried out by nitrogen fixing bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where do you find nitrogen fixing bacteria?

A

Free living or in the root nodules of legumes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What you can describe the relationship between nitrogen fixing bacteria and legumes as?

A

Mutualistic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why is the relationship between nitrogen fixing bacteria and legumes mutualistic?

A

Bacteria gets the carbohydrates they need to live and protection and the plant gets nitrite ions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does lightning add nitrogen to the soil?

A

The huge amount of energy in lightning allows nitrogen and oxygen to be combined forming nitrite ions which are held in the cloud until it rains and when it rains they eventually dissolve into the soil.

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

What happens during ammonification?

A

Decomposers decay the excretory products and detritus into ammonia. This is done by saprobiontic nutrition.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is detritus?

A

Dead material

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

What happens during nitrification?

A

Ammonia is converted into nitrites and then the nitrites are converted into nitrates carried out by nitrifying bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the symbol for nitrites?

A

NO₂

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the symbol for nitrates?

A

NO₃

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How can nitrogen be removed from the soil?

A

Denitrification.

20
Q

What happens during denitrification?

A

Nitrates are converted into nitrogen gas by denitrifying bacteria.

21
Q

Where is denitrification most likely to happen?

A

In anaerobic conditions like water logged fields.

22
Q

What is the main process that adds CO2 to the environment and the main process that removes CO2 from the environment?

A

Respiration adds, photosynthesis removes.

23
Q

Why do the amounts of atmospheric CO2 change?

A

The amount of respiration and photosynthesis varies on a daily basis and a yearly basis.

24
Q

What happens to CO2 concentration during the day?

A

CO2 concentration falls because it is removed by plants as they carry out photosynthesis and more is being removed than is being added by respiration.

25
Q

Why does CO2 concentration increase at night?

A

Because it is no longer being removed by photosynthesis but all organisms are still respiring and adding CO2 to the environment.

26
Q

How does CO2 concentration change on a daily basis?

A

It falls during the day and increases during the night.

27
Q

How does CO2 concentration change on a yearly basis?

A

It falls during the summer months and increases throughout autumn and winter.

28
Q

Why does CO2 concentration fall during summer?

A

Most plant growth occurs during the summer because that is when light intensity is greatest so more photosynthesis can occur so more CO2 is being removed.

29
Q

Why does CO2 concentration increase throughout autumn and winter?

A

Plants don’t photosynthesise as much so less CO2 is being removed.

30
Q

Give an example of how human activity can change CO2 concentration?

A

Near traffic there will be more CO2 because the cars release it in their exhaust fumes.

31
Q

What is global warming?

A

The increase in average global temperature.

32
Q

What has human activity enhanced to cause global warming?

A

The greenhouse effect.

33
Q

What is the greenhouse effect?

A

When the greenhouse gases absorb outgoing energy so that less is lost meaning more energy and heat is trapped within the earth’s atmosphere.

34
Q

What are the two main greenhouse gases in the atmosphere?

A

CO₂ and Methane.

35
Q

What 4 human activities increase CO2 concentration?

A
  1. Burning Fossil Fuels
  2. Farming
  3. Deforestation
  4. Destruction of natural sinks
36
Q

What are 3 reasons why methane concentration is increasing?

A
  1. More rice fields
  2. More cattle
  3. More is being released from natural stores.
37
Q

Why is more methane being released from natural stores?

A

As the temperature increases the stores will thaw and release large amounts of methane into the atmosphere.

38
Q

What can global warming lead to?

A

Climate change.

39
Q

Give 2 examples of climate change.

A
  1. different rainfall patterns

2. changes to seasonal weather patterns.

40
Q

How can crop yield be affected by CO2 concentration?

A

Increasing CO2 concentration increases the crop yield as CO2 is a limiting factor of photosynthesis.

41
Q

How can climate change affect insect pests?

A

It can affect the lifecycle of some insect species and affect the numbers of some species.

42
Q

How can climate change affect animals and plants?

A

It can affect the distribution of numbers of wild animals and plants.

43
Q

What is an environmental disadvantage of using fertilisers?

A

Eutrophication

44
Q

Describe Eutrophication in 10 steps

A
  1. Fertilisers are spread into fields to improve growth of crops.
  2. Rain water leaches the fertiliser into streams, rivers and lakes.
  3. Mineral salts from the fertilisers causes rapid growth of the algea in the water.
  4. The algae forms a blanket over the water blocking out the light
  5. Plants of the bottom die because they cannot photosynthesise
  6. Algae die when the mineral salts are used up
  7. Bacteria start to decompose the dead plant material.
  8. Bacteria reproduce rapidly using the dead plant material as food.
  9. Bacteria respires continually using up the dissolved oxygen in the water.
  10. Animal life dies due to lack of oxygen.
45
Q

Draw a photo of the carbon cycle.

A

,

46
Q

Draw a photo of the nitrogen cycle.

A

,

A2 Biology - unit 4 (8 decks)

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