Nutrient cycles ( 2016-2021)

Question 1

Describe the role of saprobionts in the nitrogen cycle.

Answer 1

break down proteins into ammonium compounds

Question 2

Describe how you would obtain a quantitative measurement of their
cloudiness.

Answer 2

• colorimeter
• measure the amount of light absorbed
• use the same wave length

Question 3

Suggest why, in this investigation, the scientists used these units.
μg and g–1

Answer 3

1.small concentration
2.comparisons

Question 4

Explain how groups A and C act as controls.

Answer 4

so x in A could be seen
so y in C could be seen

Question 5

Explain why determination of dry mass was an appropriate method to use
for plants

Answer 5

• measures the increase in organic material
• water content varies on plants

Question 6

how do you evaluate ?

Answer 6

• overall pattern (most effective least effective anomalies)
• statistics
  -time
• representative ( number of species completed on)
• control

Question 7

Suggest one way in which an increase in the uptake of phosphate could
increase plant growth.

Answer 7

for ATP for photosynthesis to produce glucose used to make proteins

Question 8

explain why health growth of most plants need nitrogen form the SOIL ?

Answer 8

cant abosr nitrogen form the air
nitrates needed for protein synthesis for growth

Question 9

how does atmospheric nitrogen get converted into nitrates ?

Answer 9

nitrogen fixing bacteria in nodules of leguminous plants or soil convert nitrogen into ammonium compounds
nitrifying bacteria convert ammonium bacteria into nitRITES
and other nitrifying bacteria convert niTRITES to nitRATES

Question 10

2 processes that lead to a reduction in nitrate concentration

Answer 10

de nitrification
- converts nitrates into nitrogen

leaching
-nitrates get dissolved in water