environment

Question 1

what is a monoculture

Answer 1

growing single variety of plants( crops) in a large area

Question 2

negative effects of monoculture

Answer 2

low biodiversity
increase in the population of pest of the crop
destroying habitats for animal

Question 3

the negative impact of intensive livestock production

Answer 3

spread of diseases

the waste can pollute the land or the river

Question 4

what is the usual factor for famine

Answer 4

weather

Question 5

effect of deforestation

Answer 5

if the tree is cut, the soil under will be exposed to rain.
this will make soil thin.
it can be washed away and this will cause soil erosion
as well as a flood if they get into the river.

less rainfall because not many trees will absorb and tranpirate them

Question 6

give two examples of greenhouse gases

Answer 6

carbon dioxide and methane

Question 7

how does the greenhouse effect happen

Answer 7

shortwave radiation from the sun hits the ground
the ground absorb and emitted out longwave radiation
greenhouse gas will reflect back the longwave radiation make the earth get heated again

Question 8

what is the main source of production of carbon dioxide

Answer 8

burning fossil fuels

Question 9

what we could do to reduce methane production

Answer 9

recycle rubbish more because the decay of rubbish creates methane

Question 10

which two gases cause acid rain

Answer 10

nitrogen dioxide, sulfur dioxide

Question 11

how does acid rain affect plant’s growth

Answer 11

it washes out ions which are essential nutrients for the plant. also difficult for plant to absorb nutrients in the soil

Question 12

how does acid rain affect river

Answer 12

ions will wash into the river, some ions are poisonous to the organism in the liver ( aluminium ion)

water will be acidic

Question 13

what will be the usual cause of eutrophication

Answer 13

fertilisers and untreated sewage

Question 14

describe the process of eutrophication

Answer 14

the (nitrate) fertiliser make the algae grow fast
algae cover the top surface of the river
light can’t be reached the plants under water
can’t do photosynthesis so dies.
less plant will do photosynthesis so oxygen level decrease and also the bacteria will decompose the dead plant, this will also reduce oxygen
the fish in the lake will lack oxygen so it dies, bacteria will need even more oxygen to decompose them
eventually, all the living organisms in the river will die due to a lack of oxygen

Question 15

what is a DDT

Answer 15

a pesticide that kills insects

Question 16

how does DDT spread to the whole food chain

Answer 16

animal placed in the higher place of the food chain will have a greater concentration of DDT

for example, the insect gets DDT and get eaten by shrimps
shrimps are eaten by fish
fish eaten by bird

DDT can’t be break down so it will compile in the organism

Question 17

what is non-biodegradable mean

Answer 17

it cannot be broken down by decomposers

Question 18

effect of plastic in the environment

Answer 18

they may harm animal by choking them or they stuck in their stomach which can’t be digested so animal dies from lack of nutrient because they cant eat food

Question 19

what are sustainable resources

Answer 19

a resource that is produced rapidly as it is removed from the environment

Question 20

purpose of sewage treatment

Answer 20

remove harmful micro-organisms in the sewage that can harm the environment and people

Question 21

process of sewage treatment

Answer 21

grit and sand is removed by the screen

solid waste is removed in first settling tanks

then it goes to the aeration tank, where aerobic microorganisms grow and feed on the organic matter

then it goes to the second settling tank, where microorganism sink and returned back to the aeration tank

the pure water now is sent to the river

the sludge is passed to a digester so it can produce methane which can be used as a fuel

Question 22

what is sustainable development

Answer 22

providing needs for the human without harming the environment

Question 23

factors that endanger species

Answer 23

hunting, habitat destruction, pollution, introduced species

Question 24

way to keep up a particular species of fish

Answer 24

breed large number of them in hatcheries and then release them