1.2 - Cycles In Nature

Question 1

What are living things made up of?

Answer 1

Carbon, phosphorus, nitrogen and sulphur compounds

Question 2

Elemental composition of fats

Answer 2

C, H and O

Question 3

Elemental composition proteins

Answer 3

C, H, O, N and S

Question 4

Elemental composition of carbohydrates

Answer 4

C, H and O

Question 5

Elemental composition of nucleic acids

Answer 5

C, H, O, N and P

Question 6

What are the two types of decompositions?

Answer 6

Aerobic (decomposition of oxygen) and anaerobic (decomposition without oxygen)

Question 7

What is aerobic decay?

Answer 7

Decomposition with oxygen

Question 8

What is anaerobic decay?

Answer 8

Decomposition without oxygen

Question 9

Aerobic decay product of Carbon

Answer 9

CO2 - carbon dioxide

Question 10

Anaerobic decay product of Carbon

Answer 10

CH4 - Methane

Question 11

Aerobic decay product of Sulphur

Answer 11

SO42- sulphate

Question 12

Anaerobic decay product of Sulphur

Answer 12

H2S - hydrogen sulphide

Question 13

Aerobic decay product of phosphorus

Answer 13

PO43- - phosphate

Question 14

Anaerobic decay product of phosphorus

Answer 14

PH3 - phosphine

Question 15

Aerobic decay product of nitrogen

Answer 15

NO3- - nitrate

Question 16

Anaerobic decay product of nitrogen

Answer 16

NH3 - Ammonia

Question 17

What are the two most important natural cycle reactions

Answer 17

Photosynthesis and respiration

Question 18

What is photosynthesis

Answer 18

Photosynthesis is an endothermic and photochemical reaction that removes Carbon Dioxide (CO2) from the atmosphere and replaces it with Oxygen (O2) its also stores energy in glucose molecules

Question 19

Write the chemical reaction of photosynthesis

Answer 19

include the chemical reaction of photosynthesis

Question 20

What is respiration

Answer 20

Respiration is an exothermic reaction that results in the creation Carbon Dioxide (CO2), Water (H2O gas) and energy

Question 21

Write the chemical reaction of respiration

Answer 21

include the chemical reaction of respiration

Question 22

What are the fertiliser compounds

Answer 22

Ammonium nitrate, ammonium sulphate and Urea (CO(NH2)3)

Question 23

Draw the molecular formulae for Urea

Answer 23

include photo of the molecular formula

Question 24

Why do plants need Nitrogen

Answer 24

Promotes root development and leaf growth

Required for formation of nucleic acids, proteins and chlorophyll

Question 25

what is chlorophyll

Answer 25

Found in chloroplasts in the plant, is a green pigment and assists in the reaction of photosynthesis

Question 26

Why do plants need phosphorus

Answer 26

Regulates leaf growth and size

Required for formation of nucleic acids and the formation of energy molecules ATP and ADP

Question 27

What are phosphorus fertilisers

Answer 27

Compounds of Sodium and potassium phosphate or compounds containing Dihydrogenphosphate ion (H2PO4-)

Question 28

Describe the process of photosynthesis

Answer 28

An endothermic and photochemical reaction which converts carbon dioxide and water into oxygen and glucose with the assistance of sunlight and chlorophyll

Question 29

Describe the operation of the nitrogen cycle

Answer 29

NC follows the movement of nitrogen, in the form of various compounds, in the atmosphere, soil, plants and animals.
Lightening provides energy to convert N2 into NO. This reacts with O2 to form NO2. Both oxides then react with rainwater and are washed to the ground as nitrite and nitrate where they are absorbed by plant roots.
Nitrogen fixing bacteria converts N2 into NH4+ or NH3 these are converted into nitrate by nitrifying bacteria.
When plants and animals decay, they produce nitrate and ammonia.
Denitrifying bacteria convert nitrate into N2