PMR ExaminationPMR Examination

SCIENCE PAPER 2007SCIENCE PAPER 2007

11(a) (i) shows some example of the organization of cell (a) (i) shows some example of the organization of cell in the human body. Which of the following is an organ? in the human body. Which of the following is an organ? Tick (Tick (√) in the box provided.√) in the box provided.

( 1 marks)( 1 marks)

√

ANSWER:ANSWER:

1.(a) (i) – 1 marks1.(a) (i) – 1 marks

(ii) Circle the words in the box below to show two (ii) Circle the words in the box below to show two

other example of organs.other example of organs.

ANSWER:ANSWER:

(ii) nose, lungs- 2 marks(ii) nose, lungs- 2 marks

Ovum Muscle Nose LungsOvum Muscle Nose Lungs

(b) Draw lines to match each types of cell with (b) Draw lines to match each types of cell with its funtionns.its funtionns.

Carries oxygen to all Carries oxygen to all parts body. parts body.

Sends information in Sends information in the body. the body.

Destroys bacteria Destroys bacteria

Involved in reproduction Involved in reproduction

ANSWER:ANSWER:

(b) (b) CellCell FunctionFunction

Carries oxygen to all Carries oxygen to all parts of the bodyparts of the bodySends information in Sends information in

the the bodybodyDestroy bacteriaDestroy bacteriaInvolved in Involved in

reproductionreproduction

3 marks3 marks

22. Diagram 2.1 shows an activity to study the factors . Diagram 2.1 shows an activity to study the factors that affect the stability of Table P and Table Q.that affect the stability of Table P and Table Q.

(a)(a) State two factors that affect the stability of the tableState two factors that affect the stability of the table1.The base area of the table1.The base area of the table2. The height of the center of gravity - 2 marks2. The height of the center of gravity - 2 marks

(b) Based on Diagram 2.1, which table will topple first when the (b) Based on Diagram 2.1, which table will topple first when the wooden plank is tilted? Explain why?wooden plank is tilted? Explain why?

Table Q:Table Q:Reason: It is less stable because its base area is smaller and its centre Reason: It is less stable because its base area is smaller and its centre

of gravity is higher.of gravity is higher.

2 marks2 marks

(c) Diagram 2.2 shows a giraffe and a crocodile(c) Diagram 2.2 shows a giraffe and a crocodile

ANSWER: ANSWER:

(i) How does a giraffe achieves its stability when it drinks from (i) How does a giraffe achieves its stability when it drinks from a river?a river?

(i) It spreads the legs wider / lower its body.1 mark

(ii) Why is a crocodile more stable than a giraffe?(ii) Why is a crocodile more stable than a giraffe?(ii) The base area of the crocodile is larger and its centre of (ii) The base area of the crocodile is larger and its centre of

gravity of lower than that of giraffe. 1 gravity of lower than that of giraffe. 1 markmark

33. Diagram 3 shows the apparatus set-up to study the . Diagram 3 shows the apparatus set-up to study the effect of heat on calcium carbonate.effect of heat on calcium carbonate.

(a)(a) (i) What is liquid W?(i) What is liquid W? (a)(i) Limer water/ calcium hydroxide(a)(i) Limer water/ calcium hydroxide

1 mark1 mark

(ii) What can be observed happening to (ii) What can be observed happening to liquid W at the end of this experiment?liquid W at the end of this experiment?It return chalky - 1 markIt return chalky - 1 mark

(b) Complete the word equation for this reaction.(b) Complete the word equation for this reaction.

Calcium carbonate HeatedCalcium carbonate Heated

1 mark1 mark

Calcium oxide

Calcium dioxide++

(c) What conclusion can be from this (c) What conclusion can be from this study?study?

Calcium carbonate decompose when heated Calcium carbonate decompose when heated to produce calcium oxide and carbon dioxide. to produce calcium oxide and carbon dioxide.

1 mark1 mark

(d)(d) Suggest how slaked lime can be from Suggest how slaked lime can be from pieces of sea shells?pieces of sea shells?

Heat up the pieces of sea shells strongly. It Heat up the pieces of sea shells strongly. It decomposes into calcium oxide and carbon decomposes into calcium oxide and carbon dioxide. Some water is added to the calcium dioxide. Some water is added to the calcium oxide and slaked lime is formed.oxide and slaked lime is formed.

1 mark1 mark

4.4. Diagram 4.1 shows the apparatus set-up for an Diagram 4.1 shows the apparatus set-up for an electric circuit to study the relationship between electric circuit to study the relationship between voltage, current and resistance.voltage, current and resistance.

(a)(a) What is apparatus Z?What is apparatus Z?(a) Ammeter(a) Ammeter 1 mark1 mark

(B) State the function of X and of Y. 2 mark(B) State the function of X and of Y. 2 mark

ApparatusApparatus FunctionsFunctions

XX Measure the potential differences Measure the potential differences across the cells.across the cells.

YY It changes the values of resistance It changes the values of resistance in the circuit and hence the current in the circuit and hence the current

that flows through the cir circuit.that flows through the cir circuit.

(c) Based on Diagram 4.1, (c) Based on Diagram 4.1, suggest one waysuggest one way to reduce the to reduce the reading of apparatus Z. reading of apparatus Z. 1 mark1 mark

Adjust Y to a higher value / reduce the number of cells.Adjust Y to a higher value / reduce the number of cells.

(d) Diagram 4.2 shows a parallel circuit. 2 marks (d) Diagram 4.2 shows a parallel circuit. 2 marks M1 and M2 are two identical bulbs. The resistance of each M1 and M2 are two identical bulbs. The resistance of each

bulb is 2 ohms and the current in the circuit is 6 A. bulb is 2 ohms and the current in the circuit is 6 A. Calculate the voltage in the circuit.Calculate the voltage in the circuit.

1 : 1 : 1 1 + + 11 R 2 2 R 2 2 R : 1 R : 1 V: 1 R V: 1 R : 6 x 1 : 6 V: 6 x 1 : 6 V

5. Diagram 5.1 shows a pair of pliers.5. Diagram 5.1 shows a pair of pliers.

(a) (i) What is the class of level of the pair of pliers?(a) (i) What is the class of level of the pair of pliers? First class lever First class lever 1 mark1 mark

(ii) State one reason for the answer in 5 (a) (i).(ii) State one reason for the answer in 5 (a) (i). The fulcrum is between the load and the effort. The fulcrum is between the load and the effort. 1 mark1 mark

(b) Based on Diagram 5.1, why is it easier to cut the wire when we (b) Based on Diagram 5.1, why is it easier to cut the wire when we hold the pliers at K rather than at L?hold the pliers at K rather than at L?

The further the effort from the fulcrum, the greater is the effect. The further the effort from the fulcrum, the greater is the effect. 1 mark1 mark

(c) Diagram 5.2 shows a worker carrying a load using a (c) Diagram 5.2 shows a worker carrying a load using a wheel-barrow. Draw a lever system for the wheel-barrow and wheel-barrow. Draw a lever system for the wheel-barrow and the label position of load, force and fulcrum. 2 marksthe label position of load, force and fulcrum. 2 marks

Answer:Answer:

(d) Diagram 5.3 shows a system when a forces and a (d) Diagram 5.3 shows a system when a forces and a load are balanced.load are balanced.

Calculate load W when the system is in Calculate load W when the system is in equilibrium. Use the following formula:equilibrium. Use the following formula:

W X 100 : 50 x 20 W X 100 : 50 x 20

W : 10 NW : 10 N

Load x Distance of load : Force x Distance of forceLoad x Distance of load : Force x Distance of force

from the fulcrum from the fulcrum from the fulcrum from the fulcrum

(e) Diagram 5.4 shows two person , (e) Diagram 5.4 shows two person , PP and and QQ rowing their boats. rowing their boats. Why does P use less force Why does P use less force than Q to orw his boat? 1 markthan Q to orw his boat? 1 mark

In P, the distance of force from the fulcrum In P, the distance of force from the fulcrum is alrger.is alrger.

6.6. Diagram 6.1 shows how human eye can Diagram 6.1 shows how human eye can see.see.

(i)(i) State one difference between object Q and image I. State one difference between object Q and image I.

1 1 markmark

The image I is smaller / The image I is invertedThe image I is smaller / The image I is inverted

(ii) How the does size of image I change when the eye is 10cm (ii) How the does size of image I change when the eye is 10cm from object Q? from object Q? 1 mark1 mark

The image becomes largerThe image becomes larger

(iii) State one reason for the answer in 6 (a) (ii).(iii) State one reason for the answer in 6 (a) (ii). 1 mark1 mark

--> The nearer the object to the lens, the larger the images.--> The nearer the object to the lens, the larger the images.

(b) (i) Complete Diagram 6.2 to show the formation of (b) (i) Complete Diagram 6.2 to show the formation of an image of a distant object on the retina of the eye of an image of a distant object on the retina of the eye of a short sighted person.a short sighted person.

ANSWER: (b) (i)ANSWER: (b) (i)

(ii) What causes the situation in (ii) What causes the situation in Diagram 6.2 to happen? 1 markDiagram 6.2 to happen? 1 mark

The eyeball is longer than The eyeball is longer than normal / The lens is too thick.normal / The lens is too thick.

(iii) How can the situation in (iii) How can the situation in Diagram 6.2 be corrected? 1 markDiagram 6.2 be corrected? 1 mark

Use suitable convace lenses Use suitable convace lenses to correct this situation.to correct this situation.

Section B ( 20 MARKS)- Answer all questionSection B ( 20 MARKS)- Answer all question

77. Diagram 7 shows four types of plants that . Diagram 7 shows four types of plants that reproduces vegetatively.reproduces vegetatively.

(a)(a) State the parts of the plants that can reproduce State the parts of the plants that can reproduce vegetatively.vegetatively. 4 marks 4 marks (i) Ginger: (i) Ginger: Ryizome /Horizontal underground stemRyizome /Horizontal underground stem (ii) Bryophyllum: (ii) Bryophyllum: LeafLeaf(iii) Potato: (iii) Potato: Tuber / swoolen underground stemTuber / swoolen underground stem(iv) Banana Tree: (iv) Banana Tree: Stucker / shoot growing from the base Stucker / shoot growing from the base of stem.of stem.

(b) Classify the plants in Diagram 7 into groups based (b) Classify the plants in Diagram 7 into groups based on their common characteristics.on their common characteristics. 4 marks 4 marks

Common characteristicsCommon characteristics

Name of the plantsName of the plants

Ginger, Bryophyllum, Potato, Banana TreeGinger, Bryophyllum, Potato, Banana Tree

ReproduceThrough stem

Reproduce through leaf

Ginger, potatoBanana tree

Bryophyllum

8.8. Diagram 8.1 shows the apparatus set-up the initial Diagram 8.1 shows the apparatus set-up the initial temperature reading of distilled water in an experiment. temperature reading of distilled water in an experiment. The distilled water is heated. The distilled water is heated.

(a)(a) Record the initial temperature of the Record the initial temperature of the distilled water.distilled water.28.528.5°°c c 1 mark1 mark

(b) Table 8.1 shows the result of his (b) Table 8.1 shows the result of his experiment.experiment. 3 marks 3 marks

Time / minTime / min 22 44 66 88 1010

TemperatureTemperature°C°C 5050 7070 9090 100100 100100

State the variables involved in this experiment.State the variables involved in this experiment.(i)Manipulated variable : (i)Manipulated variable : Time taken to heat the Time taken to heat the distilled waterdistilled water(ii)Responding variable: (ii)Responding variable: Temperature of distilled Temperature of distilled waterwater(iii) Constant variable: (iii) Constant variable: Volume of distilled water / Volume of distilled water / type of watertype of water

(c) State a hypothesis based on the result in (c) State a hypothesis based on the result in Table 8.1Table 8.1 The longer the time taken to heat the The longer the time taken to heat the distilled water, the higher is its temperature. distilled water, the higher is its temperature. 1 mark1 mark

(d) For this part of the question, use the graph (d) For this part of the question, use the graph paper provided on next page. Based on Table paper provided on next page. Based on Table 8.1, draw a graph of temperature against time. 8.1, draw a graph of temperature against time.

1 mark1 mark

(e) Based on the graph drawn in 8(d), (e) Based on the graph drawn in 8(d), (i) predict the temperature of the distilled water at (i) predict the temperature of the distilled water at the 12the 12thth minute. minute. 1 mark 1 mark

100 100°°cc (ii) state the relationship between the temperature (ii) state the relationship between the temperature and time. and time. 1 1 markmark When the time increase, the temperature When the time increase, the temperature increase. The temperature becomes constant after increase. The temperature becomes constant after 8 minutes.8 minutes.

Graph for question 8 (d)Graph for question 8 (d)

Temperature / Temperature / °C°C

110110

100100

9090

8080

7070

6060

5050

4040

3030

2020

1010

00 22 44 66 88 10 Time/min10 Time/min

Answer for question 8 (d)Answer for question 8 (d)

f) This experiment is repeated by replacing distilled f) This experiment is repeated by replacing distilled water containing salt (water containing salt (impure waterimpure water). This salt solution ). This salt solution is heated.is heated.

Time / minTime / min 00 22 44 66 88 1010 1212

Temperature / Temperature / °C°C 3030 5050 8282 9595 102102 105105 106106

(i)(i) Based on the Table 8.1 and Table 8.2Based on the Table 8.1 and Table 8.2What is your inference about the boiling point of What is your inference about the boiling point of salt solution?salt solution? 1 mark 1 mark The boiling point of salt solution is higher than the The boiling point of salt solution is higher than the boiling point of distilled water.boiling point of distilled water.

(ii) (ii) What can you deduce about the meaning What can you deduce about the meaning of impure water?of impure water? 1 mark 1 mark Impure water is water that contains dissolved Impure water is water that contains dissolved substances/ Impure water is water with boiling point substances/ Impure water is water with boiling point above 100 above 100 °C.°C.

FINISH !!FINISH !!