Carbon, Water and Nitrogen Cycles

Question 1

Where does carbon begin (carbon cycle)

Answer 1

CO2 in air and water (rain)

Question 2

How does carbon transfer to plants (carbon cycle)

Answer 2

Photosynthesis, carbon atoms fix from carbon dioxide into organic compounds like glucose

Question 3

Where does carbon go from plants and how(carbon cycle)

Answer 3

Goes to animals through feeding where carbon atoms in organic compounds are passed along food chains Or through death turns into dead plant material

Question 4

Two process which take carbon from animals (carbon cycle)

Answer 4

Respiration which produces inorganic compounds, broken down to release energy Death/excretion

Question 5

What processes happen to dead plant and animal material (carbon cycle)

Answer 5

Fossilisation when dead organic material doesn’t fully decay, eventually used as fossil fuels Respiration and carbon goes back into CO2 from respiration of decomposers

Question 6

After fossil fuels (carbon cycle)

Answer 6

Combustion where carbon is released into the atmosphere

Question 7

Assimilation

Answer 7

Plants get some of their nitrogen by absorption of nitrate ions via their roots

Question 8

Feeding

Answer 8

Animals get all of their nitrogen (which has already been assimilated into organic molecules) by feeding on other animals or plants

Question 9

Ammonification

Answer 9

Decomposition by decomposers of dead plant and animal material produces ammonia from organic compounds

Question 10

Nitrification

Answer 10

The ammonia is first oxidised to NITRITE and then to NITRATE

Question 11

Nitrogen fixation

Answer 11

Free living nitrogen fixing bacteria in soil or symbiotic bacteria in root nodules can fix nitrogen (N2) from the air (NH4+) which is then used by the bacteria or symbiotic plant to make amino acids and proteins

Question 12

Denitrification

Answer 12

Denitrifying bacteria use nitrate in the soil and convert it back into nitrogen

Question 13

Water cycle

Answer 13

Precipitation –> Run off into streams and rivers –> (Absorption by plants –> transpiration) evaporation –> water vapour in air –> condensation (into clouds)

Question 14

Label this image

Answer 14

a- protein in plants

b- protein in animals

c- protein in detritus

d- protein in these bacteria

e- nitrogen gas in the soil

f- nitrate (NO3)

g- nitrite (NO2)

h- ammonia (NH3)

Question 15

Label this image

Answer 15

a- feeding

b- death

c- death

d- nitrogen fixing bacteria in the soil

e- nitrogen fixing bacteria in root nodules

f- MISTAKE

g- nitrifying bacteria

h- decomposers

i- nitrifying bacteria

j- absorption and assimilation

k- denitrifying bacteria

l- death