Ecosystems

Question 1

Decomposers

Answer 1

Organisms which decomposes organic material.

Question 2

Community

Answer 2

Multiple populations of species in a given area

Question 3

Mutualism

Answer 3

Both species benefit
E.g. pollination

Question 4

Commensalism

Answer 4

One species benefits and the other has no cost.

Question 5

Competition

Answer 5

Competing for a common resource.

Question 6

Predation

Answer 6

Any predictor prey realtionship

Question 7

Parasitism

Answer 7

One species benefits while the other loses out.
E.g. isopod and fish

Question 8

What are examples of dynamic changes to an ecosystem.

Answer 8

Predictor prey
Seasons
Tides
Erosion
Natural disasters

Question 9

Producer

Answer 9

An organism which produces its own food through inorganic substances such as carbon dioxide and ammonia

Question 10

What is a heterotroph

Answer 10

An organism which can’t manufacture its own food therefore finds its own food

Question 11

What percentage of energy is of inappropriate wavelengths for transfer of energy in a plant.

Answer 11

50%

Question 12

What percentage of energy is reflected from the surface of the leaf?

Answer 12

5%

Question 13

What percentage of energy is absorbed for transfer of energy in a plant

Answer 13

40%

Question 14

What percentage of energy passes through the leaf.

Answer 14

5%

Question 15

What percentage of energy in a plant is lost to respiration.

Answer 15

5%

Question 16

What percentage of energy in a plant is lost to photosynthesis?

Answer 16

33%

Question 17

What percentage of energy in a plant is lost to storage (starch)?

Answer 17

2%

Question 18

Why isn’t all of the energy from the sun transferred to each organism which eats another.

Answer 18

Energy is lost through:
Excretion
Death
Heat
Some biomass indigestible.

Question 19

How can the amount of energy/number of organisms/biomass available to the next organism be represented?

Answer 19

With pyramids.

Question 20

What is scale?

Answer 20

Amount of dry mass of organisms at each level of the food chain

Question 21

What is biomass?

Answer 21

The mass of material in all living organisms

Question 22

How do light banks increase productivity?

Answer 22

Can control duration of light causing longer growth periods
And is more efficient.

Question 23

Crop rotations effects on productivity?

Answer 23

It adds nutrition to the soil.

Question 24

Pest control and irrigation effect on productivity?

Answer 24

Less loss of biomass
Water is a limiting factor.

Question 25

How can we maximise secondary productivity?

Answer 25

No waste food No movement Warmth Antibiotics Killed young

Question 26

Disadvantages of maximising secondary productivity.

Answer 26

Restricted movement may cause osteoporosis Unnatural conditions cause stress

Question 27

What is a decomposer

Answer 27

An organism that eats dead organisms, fallen leaves etc and breaks them down into simpler materials.

Question 28

What are animal decomposers called.

Answer 28

Detritivores

Question 29

What are saprotrophs?

Answer 29

Release digestive enzymes into the environment so they can absorb them.

Question 30

What is nitrogen fixation?

Answer 30

N2 —— NH3

Question 31

Nitrification

Answer 31

NH3 —— NO2 And NO2 —— NO3 (Ammonia to nitrite) And (Nitrite to nitrate)

Question 32

Denitrifying

Answer 32

NO3 —— N2 (Nitrate to nitrogen gas)

Question 33

Ammonification

Answer 33

Conversion of nitrogen containing organic compounds into ammonia

Question 34

What is azotobacter?

Answer 34

Bacteria in the soil that does nitrogen fixation

Question 35

what is rhizobium?

Answer 35

Bacteria in nodules by legumes which do nitrogen fixation.

Question 36

What is Nitrosomonas?

Answer 36

Free bacteria in the soil that does nitrification only in aerobic conditions. NH4 to NO2

Question 37

What is Nitrobacter?

Answer 37

Free bacteria in the soil that does nitrification only in aerobic conditions. (NO2 to NO3)

Question 38

What percentage of atmospheric gasses are nitrogen?

Answer 38

78%

Question 39

How does carbon get released back into the air in the carbon cycle?

Answer 39

Respiration and combustion

Question 40

Were is carbon stored in the carbon cycle?

Answer 40

Plants, animals, microorganisms and fossils

Question 41

How does carbon leave the atmosphere in the carbon cycle?

Answer 41

Photosynthesis

Question 42

How does carbon enter decomposers in the soil?

Answer 42

Death and decay and unite and faeces

Question 43

What is the Haber process?

Answer 43

The artificial fixation of nitrogen

Question 44

What is assimilation

Answer 44

The uptake of nitrates by plants.

Question 45

What is the only way of releasing nitrogen back into the atmosphere?

Answer 45

Denitrification.

Question 46

What are the three ways of taking nitrogen from the air to ammonia in the soil?

Answer 46

Nitrogen fixation, the Haber process and atmospheric fixation.