biology form 4 chapter 9

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Chapter 9 : Endanger Ecosystem 2014

The impact of human activities on the ecosystem

No Marking scheme Marks

(a) Diagram shows the mankind activities

Based on your knowledge in biology, explain the harmful effect of the activities to the mankind and their surroundings. Suggest ways to overcome this problem

Harmful effect to mankind and surrounding:

P1-Industries, factories, and vehicles contribute to air pollution

P2-Industries emit pollutant such as sulphur dioxide/oxide of nitrogen smoke/fine solid particles

P3-Which can cause respiratory problems/asthma/bronchitis/, irritates the eye

P4-oxides of nitrogen and sulphur dioxide dissolve in rain water to form acid rain

P5-Makes the soil acidic and unsuitable for the cultivation of crops

P6-Smoke and haze reduce light intensity cause the rate of photosynthetic decrease

P7-Which subsequently reduce crop yield

P8-Carbon dioxide lead to green house effect, result in an increase in the atmospheric

P9-Climate change occur

P10-How water is discharged into nearby lakes and river lead thermal pollution

P11-Cause instant death /reduction of aquatic species

Way to overcome :

P12-Implementation of law to reduce pollution n

P13-use unlead petrol/sewage treatment

P14-(formal and informal ) education stressing ( on the concept of recycle, reuse and renew)

P15-Reduce the burning of fossil

P16-Use alternative energy source /using renewable energy solar energy. hyfroelectric and wind power)

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(b) The world population is now growing drastically in order to fulfil the needs of the increasing population, area of lands have to be developed into housing areas, school, factories and highways

Give an evaluation on the above statement by considering g the impacts on the environment

B1-Brings more bad impact than good impact to the environment

B2-Deforestation will lead to flash flood /landslide

B3-Open burning will lead to air pollution /formation of haze

B4-More carbon dioxide (form open burning ) will trap heat

B5-Lead to green house effect /global warming

B6-Lead to changes in world climate

B7-Greenhouse effect /global warming increase the earth temperature

B8-Destroying flora and fauna

B9-Migratin of fauna/birds

B10-Lead to loss of herbs for medical purpose /timber

B11-Distruption / no more water catchment area Any 10

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© Diagram show the human activities that may threaten the ecosystem

Explain the impact of these human activities on the ecosystem

F1 Air pollution

P1 Exhaust fume released by the vehicle contain carbon dioxide/ carbon monoxide/ sulphur dioxide

P2 Smoke release by the factory contain dust / soot / lead

P3 Gases released by the factory contain carbon dioxide/ carbon monoxide/ sulphur dioxide / nitrogen oxide

P4 Nitrogen oxide and sulphur dioxide dissolve in water in the clouds

P5 Forming nitric acid and sulphuric acid

P6 Form acid rain

P7 Destroy photosynthetic tissues in leaves

P8 Reduce rate of photosynthesis

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(c) P9 Increase carbon dioxide concentration

P10 Heat is trapped by green house gases

P11 Causes green house effect // lead to increase in temperature // global warming

P12 Leads to climatic change// increase sea level// flash flood

F2 Water pollution

P13 Disposal of waste matter from industrial // domestic source into the water

P14 Causes eutrophication // increase BOD level

P15 Aquatic organism die

F3 Land pollution

P16 Disposal of domestic waste on the ground

P17 Increase the number of pest/ rat / cockroach / flies

P18 Increase disease transmission\

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(d)

Diagram Shows evidence of development urbanization and industrial practices. TI needed to develop the rises of human population

Justify the effect of unplanned development into the ecosystem 10

F1-Industries/factories /vehicles contributes to air pollution

P1-Smoke /fine solid particles can cause respiratory problem

P2-Oxides of nitrogen /sulphur dioxide dissolve in rain to produce acid rain

P3-(acid rain ) causing the soil become acidic/unsuitable for cultivation of crops/leaching of mineral/corrosion of metal

P4-Increase carbon dioxide in atmosphere causes the green house effect. global warming

F2-Industrial /domestic /agricultural activities produce waste to contribute water pollution n

P5-Agro chemical /pesticides/insecticide/used by the farmer flow into the river /lead to the poisoning of aquatic organism

P6-Agricultural run-off contain excess nitrate/Phosphate lead to eutrophication

P7-(eutrophication ) cause the BOD value will increase thus may harm the aquatic organism

P8-Effluent from electronic from electronic factories contain heavy metals/mercury/cadmium kill the aquatic organism /disturb food chain

F3-Diacharged of hot water from industries/glass building cause thermal pollution

P9-Increase the water temperature in the river causing dies of aquatic organism / increase the atmosphere temperature any 3F and any 7 P

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(e) Development that is not planned and managed properly has brought

negative effects to the ecosystem such as land erosion, flash flood, landslides, global warming, thinning of the ozone layer, climate change and the extinction of certain species

P1: The leave canopy in the forest protects the soil from excess rain water.

P2: When the forest is cleared, the soil is exposed to rain (water) / wind.

P3: this will cause soil erosion

P4:The soil that is exposed to wind will be blown to another area,

P5: while soil that is exposed to rain water will be eroded and deposited at the bottom of the river / pond /lake.

P6:The soil at the hill slopes can (also) be washed away by heavy rain water

P7: resulting in land slides.

P8: (The deposited soil will) cause the water level to increase rapidly when it rains and

P9: this will in turn cause flash floods.

P10:Wild life species will also be threatened

P11: when their habitat is destroyed.

P12: Global warming will occur

P13:due to an increase in the Earth's temperature,

P14:which is caused by excess emissions of carbon dioxide/ methane/ CFC /nitrogen dioxide (into the atmosphere).

P15:These gases trap the heat that is reflected by the Earth.

P16:The thinning of the ozone layer occurs

P17: when the ozone layer (that protects the Earth from ultraviolet radiation) is destroyed by chlorofluorocarbons (CFC).

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(f) Diagram shows a human activity and forest in a developing country

Discuss the effect of the activity to the environment

F-The diagram shows human activity which is deforestation

P1-Deforestation is the main cause for increasing the CO2 amount in the air

P2-this lead to greenhouse effect phenomenon

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(a) -Forest play an important role as carbon sink of earth which absorb vast amount of carbon dioxide for photosynthesis

-Greenhouse effect phenomenon promotes global warming

-As the temperature of world is increasing ,severe climatic change/drought occur in a certain country/melting of ice at arctic /Antarctic

-Forest also act as water catchment area where rain water is absorbed and released back as water vapour to the atmosphere

-Deforestation will cause soil erosion, because there are no more root to hold the soil

-Deforestation damages the water catchment area and leads to flash flood

-Deforestation also cause loss of biodiversity by

-destruction of natural habitat

-That leads to extinction of many animal and species

-there also destruction of recreational sites any

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(b)

Diagram also show the activities of unplanned development in that area

Discuss the effects of these activities towards the environment

F1-Deforesation /uncontrolled logging

E1-incrases the temperature of the earth because there ar less tree to absorb carbon dioxide /greenhouse effect //causes more areas to be expose to the winds an water /soil erosion//wind and water will erode the soil into river

F2-The increase in the number of motor vehicles

E2-Causes an inacrese in the concentration of carbon dioxide/carbon monoxide/lead /smoke in the air/air pollution

D3-mirrooed buildings /glass building reflect heat

E3-Cause thermal pollution

F4-Nuclaer reactor releases hot water

E4-Causes thermal pollution any 3F and 3E

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(c) Diagram show a man walking past the dry lake bed of tasik Pedu in Kedah

Name the environmental problem shown in the diagram and how it occurs

Explain ways overcome the environmental problem that you have stated 10

Drought /global warming

Criteria:

C1-increase in the carbon dioxide in atmosphere

C2-Factor which contribute to increase of carbon dioxide content in the atmosphere

C3-Increase in global temperature

C4-Factors which contribute to the increase in global temperature

E1-Extensive cutting down of trees increases the earth temperature

E2-More carbon dioxide brings about green house effect

E3-incraese carbon dioxide content in the atmosphere

E4-Carbon dioxide trap heat

E5-Building with glasses reflect heat

E6-Increase in surrounding temperature

E7-Increase the frequency of drought

Step to overcome the environmental problem

C5: reducing burning

C6: control deforestation

E1-Replacing energy of fossil fuel en energy generate form wind water

E2-Limit opens burning

E3-Limit deforestation

E4-Replacing after deforestation

E5-Promotes green world

Skill to synthesize

Q1-Ability to relate carbon dioxide content with the increase in atmospheric tempearture and means to decrease the carbon dioxide content and temperature in the atmosphere

W\Explain C1,C3,C5,C6

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(d) Diagram show a large area of forest involved in the building of a dam

Discuss the good and bad economical and environmental effect of this development

Good effect

G1-Generate hydropower electricity

G2-Aas reservoir / to store water /supply fresh water

G3-Supply water for agricultural / industries

G4-Place/site for recreation /tourism

G5-Reduce the flood problem at the down stream

Bad effect

B1-Flooded.submerged trees /habitat of the fauna and flora

B2-Less tree /plants to carry out photosynthesis

B3-Amount of CO2 n the atmosphere increase

B4-Incraese teh impact of green house effect / global warming

B5-Many species of fauna and flora extinct//reduce the biodiversity

B6-Reduce the flow of water at the downstream

B7-Cause the populations of aquatic life st the downstream reduce

B8-Reduce the land used for residential /agricultural

B9-Flooded /destroy/loss of historical building /site

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(e) The world population is now growing drastically

In order to fulfill the needs of the increasing population ,area of land have to be developed into housing areas,school,factories and highways

Give an evaluation on the statement with impacts in the environmental

E-Evaluation

1m-Impact on environment

Evluation (E)

E1-Bring more bad impact to the environment

Impact on environment (I)

I1-Deforestion will lead to flash flood .land slide

I2-Open burning will lead to air pollution /formation of haze

I3-More carbon dioxide ( from open burning ) trap heat

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I4-Lead to green house effect /Global warming

I5-Lead to changes in world climate

I6-Greenhouse effect /global warming incrass the earth temperature

I7-Destroying flora and fauna

I8-Migration of fauna/birds

I10-No more/Disrupted water catchment area

(E+any 9I)

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Acid rain


(a) Diagram shows s phenomenon X which caused by air pollution

Based on the diagram name the phenomenon and explain how it occurs 4

F -acid rain

The formation of acid rain

E1-Burning of fossil fuel coal and oil in factories/power generator station /vehicles

E2-Produces sulphur dioxide/nitrogen dioxide/carbon dioxide

E3- sulphur dioxide/nitrogen dioxide/carbon dioxide dissolve in the water vapour

-to to form sulphuric acid/nitric acid/carbonic acidE5-Fall to the earth with less than 5.0 ( This called acid rain ) Any 3 E

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(b) Describe the effect of the phenomenon on agriculture and aquatic ecosystem and suggest ways to prevent this phenomenon

effect: acid rain :

On agriculture

E1-Acid rain will increase the acidity of the earth//soil become acidic leaching of minerals

E2-Not suitable for cultivation /grow of crops

E3-cause some minerals to become insoluble and cannot be absorbed by the plants

Any 2E

On aquatic ecosystem

E1-Accumulation of insoluble aluminum ion /ions in water sources //will increase the acidity of water //reduce the water pH

E2-Kill aquatic organism /threatens aquatic life

The ways that can be taken:

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S1-Reduce teh burning of fossil fuel ( which acontains sulphur)

S2-Use alternative power source which is nature friendly instead of using the fossil fuel//use solar energy/wave energy

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(c) A group of farmers planned to develop an agriculture nearby the lake. Besides to obtaining a high agriculture yield, they suggested that the area be made into a eco-tourism area. The following are a part of the details of their planning

State the phenomena shows in both diagramsDiscuss the differences of both environmental phenomena shown in diagram A and B based on the following aspect-The cause-the effect-the ways to overcome10criteria 1. State the type of phenomena

C: Differences in the causes

E: Differences in the effects

S: Differences in the ways to overcome

F1-( the phenomena is) acid rain

The causes

C1-Combustion /burning of fossil fuels in power station /factories/motor/vehicles

C2-Release sulphur dioxide SO2 and in power stations factories/ motor vehicles

C3-Form sulphuric acid and nitric acid when combine with water vapour

C4-Fall to the earth as acid rain/hail/fog/frost/dew

The effect

Agriculture

E1-Leaching of minerals//the soil become acidic

Aquatic ecosystem :

E2-Incrase acidity in the aquatic ecosystem // kill phytoplankton //destroyed photosynthetic tissues//accumulate insoluble aluminum ions in lakes and river which kill aquatic organism

Health :

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E3-Acidicsoil release ions of certain heavy metals/ contaminate the supplynof drinking water //irritate the lungs make breathing difficult/asthma/bronchitis

E4-Corrode metal railing bridges/damage buildings/statues/ automobiles/structures made of stone /metal historical building

The ways to overcome /solution

S1-Use scrubbers ( to clean up emission from power station and industrial plants)

S2-use catalytic converters ( to clean up emission form vehicle exhausts)

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(a)

z

Based on the diagram explain the phenomenon and its effect and its effect to the environment

Facts (F) : Name of phenomenon

Explanation (E): Formation of phenomenon

Effects (Ef)

F-( the phenomenon ) is acid rain

E1-Factories /motor vechicles released large amount of oxides of nitrogen to the atmosphere

E2-and sulphur dioxide

E3-Oxides of nitrogen combines woth wter vopuor (in the atmosphere) to form sulphuric acid

E5-The rian falls as acid rain

Effect:

Ef1-May corrode buildings

Ef2-Aquatic lives may die due to acidic water /low pH

Ef3-Mineral in soil will be dissolved

Ef4-Soil become infertile /not suitable for agriculture

Ef5-Plants may die due to infertile soil/acidc soil

Ef6-The ecological balance of ecosystem disrupted

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(b) Diagram 9.2 shows the impact of human activity on environment.

Based on Diagram 9.2, discuss the good and bad effects of the human activity.

Able to discuss the good and bad effects of the human activity.

Sample answer:

Good effect:

G1-Produce goods / materials // any examples

G2-Use in daily life

G3-Motor vehicles for transport (Any 2)

Bad effects:

B1-Releases sulphur dioxide / nitrogen dioxide

B2-Dissolve in atmospheric water vapour

P1-Forms sulphuric acid / nitric acid / acid

P2-Down pour as acid rain

P3-Dissolves minerals in soil

P4-Less fertile for plant growth

P5-Releases poisonous chemicals / aluminium // other examples

P6-Water in rivers / lakes lower pH

P7-Upsets ecological balance

P8-Death of planktons / flora / fauna

P9-Destruction of food chain / web

P10-Extinction of species

P11-Acid cause leaves turn purple / death

P12-Destroy marbles / buildings // other examples

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(c) Diagram shows a phenomenon in the ecosystem due to an unplanned development

Based on diagram explain the phenomenon and its effect to the environment

P1-Factories released large amount of oxides of nitrogen and sulphiur dioxide to the atmosphere

P2-Oxides of nitrogen combines with vapour ( in atmosphere ) to form nitric acid

P3-Sulphur dioxide combine with water vapour ( in the atmoopsheree ) to form sulphuric acid

P4-The rain falls as acid rain

P5-May corrode building

P6-aquatic lives may die due to the acidic water /low pH

P7-Minerals in soil will be washed into the rivers

P8-Soil becomes infertile/not suitable for agriculture

P9-Plants may die due to infertile soil /acidic soil

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(d) Diagram 9 shows one phenomenon in the ecosystem due to an unplanned development.

Based on the Diagram 9, explain the phenomenon and its effect to the environment.

Factor + Explanation:

F – (Name the effect) (The phenomenon) is acid rain

E1 – Factors / motor vehicles / factory released large amount of nitrogen oxyde

E2 - and sulfur dioxyde

E3 – oxyde of nitrogen combine with water vapour (in atmosphere) to form nitric acid.

E4 – sulphur dioxyde combined with water vapour (in atmosphere) to form sulphuric acid.

E5 – the rain fall as the acid rain.

Effect:

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E1: may corrode the building

E2: acidic water cause aquatic animal died.

E3: minerals in soil dissolved/washed into river.

E4: soil becomes infertile / not suitable for plant to growth.

E5: Less yield / plant become die because the infertile soil.

E6: The ecological balance of ecosystem disrupt

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(e) Diagram 9 shows a newspaper cutting on one of the effect of environmental pollution

Explain the causes of the phenomena shown in diagram and the effects on the environmental and organisms

Suggest ways to minimize the effect of this phenomenon 10

C1-The cause of acid rain

C2-The effect of acid rain to the environment

C3-Sugesstion on how to overcome the problem

Cause of acid rain:

F1-The combustion of fossil fuel from power stations factories / domestic boilers/vehicles release large quantities of sulphur dioxide / SO2 and oxide of nitrogen /NO and NO2

F2-Both sulphur dioxide and oxides of nitrogen combine with water vapour in the atmosphere to form sulphuric acid and nitric acid respectively

F3-They will fall back to the earth as acid rain

F4-Rain is naturally acidic with pH about 5.6 due to the presence of dissolved carbonic acid

F5-The pH of rain is however are less than 5.0 MAX 4 marks

Effect of acid rain:

Agriculture:

F1-The soil becomes very acidic and unsuitable for the cultivation of crops

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F2-Acid rain cause the leaching of mineral such as potassium / calcium /magnesium which affect the growth of crops

Aquatic ecosystem:

F3-Acid rain cause insoluble aluminum ions to accumulate in the lakes and river. An increase in the accumulation of these ion can kill aquatic organism (such as fish/ and invertebrates)

Health:

F3-Acid rain releases the ions of certain heavy metals such as cadmium/ lead/ mercury which may contaminate / harm the supply of drinking water

F5-Increased acidity in the aquatic ecosystem also kills phytoplankton (which changes the food chain)

F6- Photosynthetic tissue is destroyed. Plant leaves turn yellow and fall off. The root are damaged and cannot absorb minerals

Building

F7-Metal railing and bridge corrode

F-Limestone/stonework/marble monument are corroded due to chemical weathering

Suggestion to overcome the problem:

F1-Cleaning up emission form power station and industrial plants with scrubber. This process involves the spraying of water trap pollutants

F2-Aleaning up emission form vehicles exhausts through the use of catalytic converters .The pollutants react with one another in the catalytic converter. The pollutant reacts with one another in the catalytic converter to produce less harmful products

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Water pollution


(a)

Diagram shows huamn activities which are carried out near a river

Explain one type of pollution that occurs at site Q

F1-water pollution

E1-Effluent /phosphate /any suitable pollutant are released from the factory release into the river

F2-Thermal pollution

E2-Hot water form teh factory is released into the river which reduce dissolves oxygen in the river

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(b) The farmer at site P spray a large amount of pesticide in their agriculture activity

Diagram show a food chain at site R

Explain why the tissue in the food contain a higher level of pesticide molecule compared to the algae

P1-Algae absorbs the contaminated water /chemicals

P2-The tadpoles feeds on the algae

P3-The chemical in the algae will accumulate in the tadpole body tissue

P4-The fish feeds on the tadpole

P5-Will cause the chemical (accumulated) in the body tissue of the tadpole

P6-The fish will have a higher concentration of chemical in their body tissues

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(c) (d) Explain the impact of human activities at site Q on humans

Impact 1 : lack of clean water supply

P1-Water effluent form factories contain numerous containmination /pollution .chemicals

P2-Leads to disease example diarrhea /cholera/any suitable example which threaten health

Impact 2 : reduction of fresh water fish/food /aquatic organism /natural resources

P1-Lack of food/protein for human /any suitable impact and explanation

P2-Destruction of food chain //aquatic organism die

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Eutrophication


(a) Diagram show the changes that occurs in a lake due to the human activities

Based in the diagram ,explain how the activities cause the changes in a lake

F-The condition of river is the result of eutrophication

P1-Farmers use fertilizer that usually contains nitrates/phosphate

P2-Fertilizer/animal waste/silage which contain nitrate /phosphate may washed out in water when they are supplied with extra nitrate/(phosphate)

P4-( they may grow sa much ) that they completely cover the water

P5-Block out the light intensity for plants growing beneath them

P6-Photosyntehsis rate reduced

P8-Plant on the top of water and beneath water eventually die

P9-Their remains are good source of food becteria//bacteria decomposed the dead plant rapidly //bacteria breed rapidly

P10-The large population of bacteria repires, using up oxygen , si there is very little oxygen left for other living organism

P11-BOD increase

P12-Those fosh /aquatic animal which need oxygen move to other areas or die any 10 P

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(b)

Explain the differences in BOD value between site P and Site R? 4

P1-the BOD value in site P is lower than site R

P2-Becayuse R is at the down stream

P3-More pollutants accumulated in R

P4-The river water flow from agriculture area /P to palm oil factory

P5-The higher/increase in organic substances in the river will increase the population f bacteria decomposition //more aquatic organism die //less oxygen dissolved in the river water (at R) /resulting the BOD to increase

impact 3: Destruction of food chain

P1-Accumulation of chemical in human

P2-Through food chains/taking fresh water food

P3-Caner /mutation /disease

When sewage is released into the pond gradually, the number and the size of aquatic animals increase but when more sewage into the pond all the aquatic animals die

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(c) Explain how this affect the pond ecosystem and the balanced of nature

sewage released gradually

E1-Sewage has nitrate and phosphate salts which encourages algae growth

E2-Algae is the main produce of food for aquatic organism will increase Sewage content increase

E3-Aquatic animal will get enough food encouraging their growth and reproduction

E4-The size and numbers o aquatic organism will thus increase

Sewage content increase

E5-Sewage increase will cause algae to grow and reproduce rapidly

E6-Algae will cover the pond surface this prevent sunlight from reaching aquatic plants at the bottom of pond

E7-The submerged aquatic pl ants will die as they cannot photosynthesis

E8-The decomposition by bacteria will take place using oxygen

E9-The dissolve oxygen level will drop

E10-Aquatic animal will die to lack of oxygen in water

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(d) Diagram show a pond nearby a factory area

Based on diagram, describe the effect of this activity to the pond, Explain the effect of this condition on the aquatic organism in pond 10

Condition of the pond is the result of eutrophication

P1-Caused by nitrate form the factories leach into the pond P2-(caused by ) leaching of nitrate/phosphate form palm oil estate

P3-Excess nutrient encourages the rapid growth of algae/algae bloom

P4-Algae grow water than their consumes , so many die 9 without being consumed form organic matter)

P5-Algae covered the surface of pond

P6-restrict the penetration of light into water cause the rate of photosynthesis in aquatic plants reduced /aquatic plant die

F2-Water pollution caused by sewage /domestic waste/human faces/garbage from rubbish dumps form residential area

P6-Pond contains a lot of organic matter

P7-The decaying organic matter

P7-The decaying organic matter is broken down by decomposing microorganism /aerobic bacteria

P8-Incrasing in the BOD result in a depletion of oxygen // reduction in the amount of dissolve oxygen in the pond

F3-Imvalance to the aquatic food web

P9-( the low level of oxygen dissolve) kills aquatic organism like fresh water shrimps/mayfly nymphs

P1o-If grow and release toxic gases / hydrogen sulphide/kill fish/tubifex worms /sludge worm appear

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(e)

Based on the detail above, explain the effect on the lake if their planning is not

managed properly.

F1 - the leaching of chemical fertilizer/phosphate/nitrate from agriculture area to the lake

E1 - Increase the fertility of the lake

E2 - Encourages eutrophication (encourage algal growth)

F2 - The growth alga prevent the light from reaching the base of the lake

E3 – This reduces and prevents photosynthesis by aquatic plant.

E4 – Reduce the oxygen release

E5 – Aquatic plants and animals die due to lack oxygen.

F3 – decomposition of dead plants, animals and organic matter by saprophytic bacteria accurse

E6 – This will decrease the dissolved oxygen content

F5 – BOD increase the water polluted

E7 – This cause the aquatic animals die.

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(d) Diagram 8.2 shows a section of a river that flows through rural and urban areas

People live in residential area complained that the river water has turned green and many

Fishes die.

Explain the phenomenon

F1 : Eutrophication occur1


Type of plants : Strawberry and rose plant.

Location : Near a natural lake.

Type of fertilizers used: Compost, lead nitrate salt, potassium nitrate, magnesium ,nitrate and phosphate

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P1 : Farmers use fertilizers that usually contains nitrates/phosphate

P2: Fertilizer/animal waste/silage which contain nitrate/phosphate

may washed out in water when it rains/leaching/run into the river.

P3: Increase the nutrient content in the river

P4 : Algae in the river grow faster (when they are supplied with extra

nitrate/(phosphate)/ Algal bloom

P5: (they may grow so much) that they completely cover the water.

P6: block the sunlight to reach the plants in the water.

P7: Rate of photosynthesis decrease/ not occur

P8 : The aquatic plants die

P9 : Bacteria decomposed dead plant

P10: Population of bacteria increase

P11: oxygen in the water used up by the bacteria

P12: Dissolve oxygen also reduced/ BOD increase

P13: Caused aquatic plants and fish die

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Thermal pollution


(a)

Explain the effect of the phenomenon on the organism in the river

F1-The phenomenon is thermal pollution

E1-Thermal pollution occurs when there is an increase in the temperature of water source or excessive heat in the environment

E2-High temperature /heat reduces the level of dissolved oxygen in water

E3-Aerobic aquatic organism will die

E4-Highg temperature can cause some aquatic organism die

E5-Increase in temparature encourage some algae to grow rapidly

E6-Lead to high BOD value F + any 3E

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The greenhouse effect


(b) The following statements are human activities in an ecosystem

The use of chlorofluorocarbon in air conditioners and refrigerator

Combustion of fossil fuel in the factories

Based on the statement, discuss how the activities endanger the ecosystem

F1-(CFC) cause depletion of ozone layer

E1-Penetration of excess /more UV rays

E2-Skin cancer/melanoma/sunburns/cataract//any suitable example

E3-Reduce body immune system

E4-Leaf cells and chlorophyll are easily damaged //lower rate of photosynthesis

E5-Kill microorganism/phytoplankton

E6-Distruption /destruction of food chain /web

E7-Climatic changes//any suitable example

E8-Surrounding temperature increases

F2-(combustion of fossil fuel) causes acid rain //air pollution

E7-Factories release a large amount of nitrogen oxide/nitrogen dioxide/sulphur dioxide/carbon monoxides/dust in the atmosphere

E8-Acid rain –soil become acidic (so less suitable for the cultivation of food chain /food web

E10-Photosynthetic tissue are destroyed//root damaged and cannot absorb mineral /water lower rate of photosynthesis

E11-Metal railing /bridges corrodes / any suitable example

E12-Health problem: asthma/bronchitis/and any suitable respiratory problem

E13-Skin and eye irritation /conjunctivitis

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(c)

(d) Figure shows an environment phenomenon

Describe how the phenomenon in figure occurs

P1-The phenomenon is the greenhouse effect

P2-Carbono dioxide ,chlorofluocarbon ( CFCs) methane , nitrous oxide and water vopour make 1

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up the green house gases

P3-Greenhouse gases produces by burning of fossil

P4-Also produced belching from cattle and anaerobic respiration in paddy field

P5-Effect of deforestation

P6-Sunlight enter the earth’s atmosphere

P7-Most of the radiation is absorb by the earth

P8-Some radiation is absorbed by th earth

P9-Accumulated/imcreased concentration of green house gases trapped the radiated heat

P10-Warm the atmosphere

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Suggest ways to minimize the effect of this phenomenon

P1-Reduce burning of fossil fuel

P2-Use alternative energy sources

P2-Slow down deforestation for farming ot rice growing

P4-Replant trees which have been cut down

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(a) Based on diagram a phenomenon which occurs in the earth’s atmosphere

Name this phenomenon and explain the effect of the phenomenon on the environment if the concentration levels of carbon dioxide, CO2 are increasing

P1-This is called the greenhouse effect

P2-The increase in carbon dioxide concentration traps heat

P3-Causes a rise in the earth’s temperature

P4-The melting of polar ice raises the sea level Any 3P

F3-Habitat destruction

E5-Extinxction of flora and fauna

E6-Loss of biodiversity

F4-Incrase of carbon dioxide in atmosphere

E7-Greenhouse effect

E8-Global warming

E9-Climatic change

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(b) Figure 7 shows the events leading to the greenhouse effect

With reference to figure 7, describe the steps involved in the formation of the greenhouse effect5 by greenhouse gases such as carbon dioxide and methane

- solar radiation warms the earth’s surface

- heat energy is reradiated back into the atmosphere

- some heat energy escapes into space

- heat energy is reradiated back to the earth

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(c) In many parts of the world, forests are being cut down and burned.

Explain why this may be contributing to the greenhouse effect.

in slash-and-burn agriculture, the burning trees increases the concentration of carbon dioxide in the atmosphere

- trees photosynthesis using carbon dioxide thus deforestation leads to less carbon dioxide being removed from atmosphere

- less carbon dioxide is able to be locked up in trees.

- As trees die and tree stumps left to rot, microbial activity during decomposition also releases carbon dioxide

- Carbon dioxide is greenhouse gas. It absorbs energy radiated by earth, some of these energy reradiated back thus increasing the surface temperature

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(d) Describe the other causes besides deforestation and the overall effects of the enhanced greenhouse effect.10

- the greenhouse effect is further worsened by the combustion of fossil fuel in motor vehicles in power stations to generate electricity and in industries

- these activities produce large quantities of carbon dioxide into the atmosphere

- the setting up of large cattle ranches to cater for the growing human population leads to massive emissions of methane gas from the belching of these animals and the decomposition of their wastes.

- As the world population strives for higher standards of living, there is an increased use of CFCs in products like air-conditioning and during the production of packaging materials

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- The rapid decomposition of humus, combustion of fossil fuels use of nitrogen or nitrate fertilizer contributes to the production of nitrogen oxides which is another greenhouse gas

- The increase in the concentration of these greenhouse gases would then lead to increasing surface temperatures on earth as they trap and reflect heat back to the earth

- This may lead to an increase in photosynthesis which is about the only positive effect of an enhanced greenhouse effect

- More alarmingly however the greenhouse effect may change the local and global climate causing a shift in vegetation and vectors

- This may also lead to extinction of certain species of organisms which are unable to adapt to the changing environment

- Glaciers may start to melt thus increasing the sea levels. This leads to flooding in low lying areas around the globe

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(e) As an environmental activist, explain the green house effect and discuss some human activities that can lead to the greenhouse effect. Give suggestion to the public on measure to be taken to reduce the greenhouse effect 10Phenomenon of green house effect:F1-the greenhouse effect is an effect in the at atmosphere as a result of presence of certain gases known as green house gasesE2-Carbon dioxide, Chlorofluorocarbon (CFCs) methane, nitrous oxide and low level ozone and water vapour make up the green house gasesE3-As the earth is warmed, heat in the form of infrared radiation is radiated back into the space. However. Much of this heat does not escape, instead remains trapped by the green house gasesE4-At the same time, greenhouse also radiated heat ( in form of infrared radiation ) back to the earth

E5-This similar to the glass planes of a green house which traps heat and warm the green house, hence the term greenhouse effect MAX 4marks

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Factors contributing t o the greenhouse effect s

F1-Burning of fossil fuel coal-fired power stations/vehicle exhausts/open burning / industrial effluents like to an increase in the amount of atmospheric co2

F2-logging /deforestation causes’ abundance amount of co2 in the atmosphere is not for photosynthesis

F3-As the concentration of green house gases rises the green house effect become more pronounced

F4-Biuliding with planes reflects more heat, thus worsen the green house effects

F5-As more heat is trapped, the earth’s average temperature rises leading to global warming

MAX 4

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(f) Suggestion on measure to be taken to minimize the problem

E1-Reduce the burning of fossil fuels to conserve energy

E2-Develop alternative sources of energy such as wind/solar/biogas/and geothermal energy

E3-Reduce deforestation for farming purposes

E4-Replanting after deforestation

E5-Polocies that control the emission of green house gases form industrial site must be reinforced and strictly implemented

E6-Promotes green world Max 2 marks

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(g)

Explain how the phenomenon happens and its effect on the environment

C: causes of the phenomenon

E: Effect of the phenomenon

F1-this s phenomenon is called green house effect

C1-combustion of fossil fuel from vehicles/factories/forest burning/coal – fire power station

C2-excessive deforestation

C3-Increase carbon dioxide concentration in the atmosphere caused by industries

C4-Pollutant/CFC/methaneE1-Carbon dioxide traps heat /infra red light /long wave radiationE2-Increase in global/ world atmospheric temperature/ cause a rise in earth temperature/global warmingE3-melting of polar ice/rise in the sea levels

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(h) Suggests measure needed to be taken to overcome the phenomenon P1-use alternative source of energy to reduce the usage of fossil fuel energy generated from wind /water solarP2-Restrict open burning/forest burning /use incineratorP3-Reduce deforestation for farming/other development projects P4-Selective harvesting /logging/cut matured tree onlyP4-Replanting more trees which have been cut down P6-The use of technology/unleaded petrol/catalytic converter

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The thinning of ozone layer


(a)

(i) State the phenomena shows in both diagrams

Discuss the differences of both environmental phenomena shown in diagram A and B based on the following aspect

-The cause

-the effect

-the ways to overcome10

criteria

1. State the type of phenomena

2. C: Differences in the causes

3. E: Differences in the effects

4. S: Differences in the ways to overcome

Diagram B

F2-( the phenomena is) thinning depletion of ozone layer

The causes

P1-Coolant in air conditioners and refrigerators/ propellants in aerosol cans/insulating foam

P2Release chlorofluorocarbon / CFC molecule

P3Ultraviolet radiation ( strikes a chlorofluorocarbon /CFC molecule and ) causes a chlorine atom to break away//break the bond to release the chlorine atom

P4Chorine atom ( collides and destroys the ozone molecule ( to form chlorine monoxide and oxygen molecule)

P5Leaf cell and chlorophyll are damaged by ultraviolet rays// lower the rate of photosynthesis//reduce crop yield

P6Ultraviolet rays kill microorganism .phyplankton//destroy//disrupt the marine food chain

P7Prolonged exposure to ultraviolet radiation lead to skin cancer / melanoma/cataract /weakened the immune system

P8-Green house effect/ global warming //damage the eggs of certain amphibians //wind patterns change //climatic changes

P9-The ways to overcome /solution

P10-Reduce/stop/ban the use of Chlorofluorocarbon /CFC

P11-The world comply with the Montreal protocol to reduce the use of CFCs ( to cut the use of CFC’s in half of CFC in half by the year 1997) Any 10

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(b) Diagram 8.2 shows another environmental phenomenon which has become a current topic discussion

Name this phenomenon and discuss the effect of the phenomenon on human and ecosystem

The phenomenon is known as thinning/depletion of the ozone layer

P1-More ultraviolet ray reaches the earth surface

P2-Ultra-violet ray will deteriorate/weaken thee human’s body immune system

P3-An increase in the number of people suffering from skin cancer/melanoma/cataract

P4-High ultraviolet rays destroy phytoplankton

P5-break the food chain of marine life/the aquatic ecosystem

P6-The number of stomata/chlorophyll of leaves will be reduced

P7-Rate of photosynthesis decreases

P8-Changes in climatic pattern F with any 5P

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(c) Explain the concept sustained development and need for it to protect our environment

F-(sustainable development refers to the measure undertaken to ensure that human activity optimally utilize Earth natural resources such that they can be replenish naturally//suitable explanation

P1-Sustainable development is necessary as the rate at which man is using the finite natural resources will compromise future generation‘s demands //suitable explanation

Necessary to exploit natural resources and at at the same time measure taken so that these resource can be replenish and be available for the future generation

P2-Ultimately, the natural resources, if continued to be depleted, will no longer be able to sustain human society//suitable explanation

P3-Which make up the surrounding we live in and survive upo n

P5-Includes proper usage of renewable resources

P6-Inorder to maintain a stable ecosystem

F + ant 3P

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The importance of proper management of development activities and the ecosystem


(a) Explain the important of preservation and conservation of tropical rainforest in Malaysia for the purpose of sustainable management of ecosystem

1. Sustainable management of tropical rainforest

2. Explain the importance o conservation and preservation

F1-replanting trees in areas that have been logged//reforestation

E1-To keep the ecosystem in their natural state (which provides aesthetic value for humans)//preserve natural resource for outdoor/recreational; activities//eco-tourism //reduce stress//promotes healthy life style

E2-To maintain soil fertility

E3-T prevent food / soil erosion/landslide/(muddy) float/(flash) flood

E4-To avoid species extinction //to prevent extinction of flora and fauna/organism /species

E5-As an economic resource//source of raw material for construction industry/piling. Furniture/boats/houses /production of charcoal/tannin /food / other suitable example //provide foods to human // resources for study /education /research

F2-Selecive logging E5-To maintain a balanced ecosystem / to allow maximum interaction among teh living organism /biotic and abiotic factors

E6-To maintain major sources of human biotic and abiotic factors

E7-Ti sustain n food web /food chain in the ecosystem

E8-To prevent disruption of natural cycle of water /carbon balance oxygen between CO2 in the atmosphere.//provide O 2 reduce CO2

E9-to decrease the carbon dioxide level in the atmosphere// to reduce the green house effect global warming

E10-to maintain the biodiversity of the forest // maintaining /increasing biodiversity /complexity/veriety of organism /species /flora and fauna

E11-To avoid lost of wildlife/ potential resources E12-To avoid loss of water areas //provide natural water catchment area

E13-Maintaining (normal) weather (pattern) by minimize climatic changes drought / harsh climate / maintain temperature

E14-As a site for breeding feeding of flora and fauna serving as valuable nursery area for organism

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(b)

Based on th above information ,Explain how recycle practice able to preserve the balance of environment 10

The tree

F1-Less tree will be chopped/felled

P1-More CO2 absorbed by the trees for photosynthesis

P2-Avoid the increasing o CO2 in the atmosphere

P3-Reudce the impact of green house effect/. Global warming

P4-Less habitat of fauna and flora will be destroyed

P5-Reduce /avoid the extinction of fauna and floraP6-To maintain /preserve the biodiversity

the oil .fuel //save energy

F2-Reudce the burning of oil /fuel

P7-More fuel energy can be preserved for future

P-Less green gases /acidic gases released

P9-Reduce/avoid the impact of green house effect /acid rain

The landfill will be opened F3-Less land fill will be opened

P10-Landfill cause leaching /.ground water pollution

P11-Less disease /health problem caused by the improper managed landfill

The Water

F4-Less used water/effluent/ untreated seawage released into river

P12-Reduce .avoid the impact of water pollution /avoid the extinction of aquatic organisms any 10

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(c) Diagram show an ecosystem

Explain why the ecosystem in diagram 8.2 has to be preserved and conserved 10

F-Ot provides human with necessities of life

P-Is a resource for food /timber to build shelter/ as a fuel/fibers for clothing

F-Many plant species are original sources of pharmaceutical drugs/medicines

P-New commodities, for example, new crop plants or medicinal material could be in the forest

F-Allow for biological control to maintain stable population

P-Regulate climatic conditions biogeochemical cycles, prevent flooding

Natural ecosystem and species in the wild are beautiful

P-there is much pleasure to be derived form unspoilt natural environment

F-Ecotourism

P-Could provide income for some countries

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A paddy field area is developed into an industrial area as shown in Diagram

Discuss the good and the bad social, economic and environmental effects of this development.

Good Effect (G) Explanation (P)

G1: Provides job opportunity P1: Improve economic status

G2: Provides infrastructure basic needs P2: Build up schools/ clinics to upgrade quality/ better opportunity in education

G3: Provides better living condition/ convenient place for settlement

P3: Have good sanitation system/ hygienic water supply/ better electric supply

G4: Convenient transport system P4: Faster transportation/ save time to move from one


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place to another

Bad Effect (B) Explanation (P)

B1: Area/ paddy field exposed to land reclamation

P5: During heavy rain, soil particles are washed away to the river/ water source leads to muddy flood/ leaching

B2: Habitat for flora/ fauna/ paddy field are destroyed

P6: Extinction of flora/ fauna in the area// less agricultural productivity in the area

B3: Air/ water/ thermal/ sound pollution P7: Due to the release of pollutants into the environments// causes diseases/ bronchitis/ asthmatic/ stress// leads to decrease in health quality

B4: Increase population in the area P8: Leads to social problems


(d) Most of the human activities cause a lot of problems to the ecosystem.

Discuss the importance of planned activities to avoid destruction of the ecosystem 10

Logging

A – uncontrolled logging can cause destruction of the habitat

E – also can caused the'extinction of flora and fauna

- destroy the water catchments-area so, it disturb the fresh water supply

- can caused the muddy flood, flash flood, soil erosion and global warming

P - So the logging activities should be planned to avoid t hose effect

- Planned logging can be done by replanting logging at the certain area which contain only old timber tree.

Motor vehicles

A - can caused air pollution because the smoke contain Plumbum, carbon monoxide, carbon d ioxide,

E – carbon monoxide can caused death if inhaled in large amount, because it reduced the ability of oxygen transportation by red blood cells

- Plumbum can cause cancer

- Carbon dioxide and heat from the smoke,it will increase the world temperature so it can cause global warming

P - So using of motor vehicle can be reduce by using car pool, use the public transportation and filter the smoke released

Open burning

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A - can cause hazard

E - it will decrease the distance of vision can increases the health problem related w ith lung and respiratory tract

P - So it can be reduce by avoid the open burning or burn the garbage in the specific place( in close area)/incinerator

Farming and A agriculture

A – Farmer used chemical fertilizer it can cause the eutrophication

E - can cause extinction of flora and f fauna

P - Use organic fertilizer or increase the fertility of the soil

OR

A_use pesticide to kill the pest, it can caused air pollution and water pollution

E-can cause extinction of flora and fauna

P-use biological control to control the population of pest

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(e) (e) Discuss the importance in maintaining a balanced ecosystem in a river

F-A balanced ecosystem ina river must be maintain

P1-When water pollution occurs//chemical content is very high

P2-Sunlight penetration is reduced/amount of dissolved oxygen very low

P3-Plants /producer do not carry out photosynthesis

P4-First consumer species/herbivores/carnivores do not receive enough energy//destruction of energy flow

P5-Very high decomposition .eutrophication

P6-Aquatic organisms die /extinct//destruction of food chain

P7-Rover becomes shallower/causing flooding over flow of water Any5

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biology form 4 chapter 9

Documents

green house effect lead

sulphur dioxide dissolve

mankind activities

impact of human activities

rain water

green house gasesp11

problem harmful effect

air pollution p2industries