Material cycles

Question 1

Which process forms clouds?

Answer 1

Condensation

Question 2

What is precipitation?

Answer 2

Rain

Question 3

What is transpiration?

Answer 3

Where water moves through plants and is lost by evaporation

Question 4

What is potable water?

Answer 4

Water which is safe to drink

Question 5

What is desalination?

Answer 5

Removal of salt from sea water

Question 6

How can desalination take place?

Answer 6

By distillation

Question 7

What are some of the problems with producing potable water by distillation?

Answer 7

Distillation requires large amounts of heat which is expensive and can produce greenhouse gasses

Question 8

During distillation, what is the purpose of the condenser?

Answer 8

Cools water vapour, turning it back to liquid water

Question 9

What are the 3 stages in the water treatment process?

Answer 9

Sedimentation, filtration, chlorination

Question 10

Why is chlorine added to drinking water?

Answer 10

To kill pathogens

Question 11

What is the word equation for photosynthesis?

Answer 11

carbon dioxide + water –> glucose + oxygen

Question 12

What is the word equation for aerobic respiration?

Answer 12

glucose + oxygen -> carbon dioxide + water

Question 13

What is the word equation for complete combustion?

Answer 13

Fuel + oxygen -> carbon dioxide + water

Question 14

Which processes can add carbon to the atmosphere?

Answer 14

respiration, combustion, decomposition

Question 15

Which processes can remove carbon from the atmosphere?

Answer 15

photosynthesis, dissolving in oceans

Question 16

How does carbon move from plants to animals?

Answer 16

Feeding

Question 17

Where do plants get nitrogen from?

Answer 17

Absorbed through roots

Question 18

How does nitrogen get from plants to animals?

Answer 18

Feeding

Question 19

How is nitrogen returned to the soil from animals?

Answer 19

Death and excretion

Question 20

How can nitrogen be fixed from the air to soil?

Answer 20

Bacteria or lightening

Question 21

What do nitrogen-fixing bacteria do?

Answer 21

Fixes nitrogen from the air into soil

Question 22

What do nitrifying bacteria do?

Answer 22

convert ammonium compounds from dead and decaying material into nitrates in the soil

Question 23

What do denitrifying bacteria do?

Answer 23

Turn nitrates in the soil into nitrogen gas in the air

Question 24

What makes legumes different from other plants?

Answer 24

nodules in the roots containing nitrogen fixing bacteria

Question 25

What is crop rotation and why is it important?

Answer 25

crop rotation means growing a leguminous plant in a field every few years. The leguminous plant fixes nitrogen into the soil using bacteria in root nodules, replenishing the nutrients in the soil

Question 26

Which types of organism cause decomposition?

Answer 26

bacteria and fungi

Question 27

What effect does increasing water content have on rate of decomposition?

Answer 27

decomposition increases

Question 28

Why does increasing water content cause rate of decomposition to increase?

Answer 28

Because decomposition reactions need water to take place

Question 29

What effect does increasing temperature have on rate of decomposition

Answer 29

rate of decomposition increases, then decreases at high temperatures

Question 30

What effect does increasing oxygen availability have on rate of decomposition?

Answer 30

Rate of decomposition increases