SCIENCE PLAZA
PLAZA SAINS
Penilaian Menengah Rendah 2010
PMR Sains
Kertas 2
Kertas 2
Disediakan Oleh Alex Ng Chan Heng,
GC Sains merangkap
Ketua Panitia Sains
SMK Taman Indah, Tampin, N.Sembilan
(Bertarikh: 18 OKTOBER 2010)
Section A
Q.01. (a) Diagram shows three laboratory apparatus P, Q and R. Name P, Q and R using the words given in the box.
P - Bunsen burner
Q - Tripod stand
R - Beaker
Q.01 (b) Draw lines to match the laboratory apparatus with its function.
Stopwatch - Measures time
Callipers - Measures diameter
Spring balance - Measures weight(a) State the name of the wire Q - Live wire
(b) Complete Table 2 by writing the international colour code used for the wire.
Type of wire International colour code
Live wire Brown colour
Neutral wire Blue colour
(c) State one function of the fuse.
A fuse is a safety device that prevents current exceeding its rating from flowing
through the cable and wires in the household circuits.It melts when a current exceeding its rating flows through it.
(d) What might happen to an electrical appliance if the wires in the 3 - pin plug are wrongly connected?
A short circuit occurs when current flows through a shorter path of lower resistance.
(e) If a 15 A curent flows through a 3- pin plug, predict what will happen to the
fuse in the plug.
If a 15A current flows through a 3-pin plug of 13A rating, the fuse wire will melt,and thus cutting of the excess current.This prevents electrical appliances from being damaged and also prevents fire from occuring.In short, the fuse blows (burns out) when a higher current flows through it, than its rating
Q3.(a) Diagram 3 shows two jars, P and Q containing fish.Both the jars are placed in a room.
(i) In which jar will the fish die first? Jar P
(ii) Give two reasons for your answer in 3(a)(i)
1.Not sufficient supply of oxygen for the fish to respire
2.Carbon dioxide produced suffocates the fish to death
(b) Explain why the fish in one of the jars can still be alive after two days.
Fish in jar Q are still alive after 2 days because there is oxygen produced by the water weeds through photosynthesis.(c) Why does a whale need to rise regularly to the surface of water?
To get enough oxygen for respiration
Q4.(a) Diagram 4.1 shows a pond ecosystem.
(i) Write the name of one population that is part of this pond population.
dragonfly population // tadpole population // fish population
(ii) State one producer. Elodea // water weeds // hyacinth
(iii) Give one reason for your answer in 4 (a)(ii).
They supply food to other consumers such as fish, tadpoles and dragonflies
(b) Diagram 4.2 shows a food web in an oil palm estate.
The number for each type of the organisms is shown in the bracket.
Based on Diagram 4.2
(i) Construct any one food chain which consists of four organisms in this habitat.
Oil palm tree -----> caterpillar -------> bird --------> snake
Oil palm tree -----> caterpillar-------->cockerel ------->eagle
Oil palm tree ----->grasshopper------->frog --------> snake
(ii) Complete the following pyramid of numbers in Diagram 4.3 using the food chain constructed in 4 (b)(i)
1. Snake 8
Bird 700
Caterpillar 800
Oil palm tree 6000
2. Eagle 3
Cockerel 50
Caterpillar 800
Oil palm tree 6000
3. Snake 8
Frog 80
Grasshopper 700
Oil palm tree 6000
5. (i) Diagram 5.1 shows two syringes P and Q, before and after compression.Syringe P is filled with substances L and syringe Q is filled with substance M.
Before compression After compression
(i) Write the state of matter of substance M. Gas// Air
(ii) State one step to increase the pressure in syringe Q.
Push the piston further down // Compress more of the air
(iii) Compare the arrangement of particles of substance L and substance M.
Particles of substance L, slightly further apart in its arrangement
Particles of substance M, arranged very far apart amongst each other
(b) Diagram 5.2 shows a student sucking water using a straw.
Based on the principle of air pressure, state why this student is able to suck the
water.
When the student sucks the straw, he is sucking out the air from the straw.A lower pressure is created in the straw.The higher atmospheric pressure on the water surface in the drinking box pushes the water up the straw.
(c) Diagram 5.3 shows a plunger used to clear a blocked pipe.
(i) Compare the air pressure at K and the air pressure at L.
Pressure at K is higher than air pressure at L. L has reduced air pressure. K is higher
atmospheric pressure.When the sucker is pressed down, air is forced out, thus creating a
lower pressure at L.
(ii) State how to use a plunger to clear the blocked pipe.
A plunger is used to clear blocked drain or sink.
-When a plunger is pushed firmly against a flat surface, air is forced out of the rubber sucker.The air pressure inside is reduced.
- The air pressure outside the rubber sucker is greater than the air pressure in the rubber sucker.
- The sucker cannot be pulled off the surface unless the seal around the edge of the plunger is broken.
- When the plunger is pulled up, the volume of air under the rubber sucker increases and this further reduces the air pressure.
-The higher atmospheric pressure then loosens the blockage
(iii) Give one reason for your answer in 5 (c) (ii).
When the plunger is pulled up, the volume of air under the rubber sucker increases and this further reduces the air pressure.The higher atmospheric pressure then loosens the blockage.
When the plunger is pulled up, the volume of air under the rubber sucker increases and this further reduces the air pressure.The higher atmospheric pressure then loosens the blockage.
6. The following are steps in an investigationto study the transport system in a plant.
Step 1: Put the plant inside a cupboard for two days
Step 2: Put the same plant under the sunlight for another two days
Step 3: Cut out a complete ring of bark including the phloem to expose the xylem
Step 4: Wipe the exposed ringed area with paraffin
Step 5: Observe the exposed ringed area for three weeks
Diagram 6.1 shows the exposed ringed area of the plant.
(a) Why is the exposed ringed area wiped with paraffin?
To cover the exposed ringed area and also to prevent the bark layer from growing again // To prevent the dehydration and also to protect the exposed phloem from being damaged //
(b) Diagram 6.2 shows the exposed ringed area before and after three weeks.
Before After three weeks
(i) What happens to the upper part of the exposed ringed area after three weeks?
It becomes swollen
(ii) Give one reason for the answer in 6 (b)(i)
Because food (starch / glucose) accumulates at the part above the ring (the upper part)
(iii) What is the function of the phloem?
To transport food from the leaves to other parts of the plant
(c) Diagram 6.3 shows the exposed ringed area covered with soil instead of paraffin.After a few months, the roots grow. This is one method of reproduction.
(i) State the type of this reproduction.
Vegetative reproduction
(ii) Give one advantage of the reproduction stated in 6 (c) (i)
Does not need pollen grain and ovules ( Only a single parent)
Vegetative reproduction is a method of producing new plants from any vegetative part of the parent plant, other than the flower. It is a type of asexual reproduction because it requires only one parent plant.
The young plants are exactly like the parent plant because they have the same genetic materials.
Parts of the plant that can reproduce vegetatively are the stem, leaf and root. Most of the vegetative parts contains stored food and buds.
(d) Diagram 6.4 shows a piece of wire tied tightly around a tree trunk.This has a negative effect on the growth of the tree after many years.
(i) Suggest one way to avoid the negative effect on the growth of this tree.
Remove the piece of wire and replace it with a nylon string
(ii) Give one reason for the answer in 6(d)(i)
The phloem and the vascular bundles are damaged due to the wires being tied tightly around the tree trunk.Thus, a bulging and protruding part is formed above the upper part of the wire after many years.
Step 1: Put the plant inside a cupboard for two days
Step 2: Put the same plant under the sunlight for another two days
Step 3: Cut out a complete ring of bark including the phloem to expose the xylem
Step 4: Wipe the exposed ringed area with paraffin
Step 5: Observe the exposed ringed area for three weeks
Diagram 6.1 shows the exposed ringed area of the plant.
(a) Why is the exposed ringed area wiped with paraffin?
To cover the exposed ringed area and also to prevent the bark layer from growing again // To prevent the dehydration and also to protect the exposed phloem from being damaged //
(b) Diagram 6.2 shows the exposed ringed area before and after three weeks.
Before After three weeks
(i) What happens to the upper part of the exposed ringed area after three weeks?
It becomes swollen
(ii) Give one reason for the answer in 6 (b)(i)
Because food (starch / glucose) accumulates at the part above the ring (the upper part)
(iii) What is the function of the phloem?
To transport food from the leaves to other parts of the plant
(c) Diagram 6.3 shows the exposed ringed area covered with soil instead of paraffin.After a few months, the roots grow. This is one method of reproduction.
(i) State the type of this reproduction.
Vegetative reproduction
(ii) Give one advantage of the reproduction stated in 6 (c) (i)
Does not need pollen grain and ovules ( Only a single parent)
Vegetative reproduction is a method of producing new plants from any vegetative part of the parent plant, other than the flower. It is a type of asexual reproduction because it requires only one parent plant.
The young plants are exactly like the parent plant because they have the same genetic materials.
Parts of the plant that can reproduce vegetatively are the stem, leaf and root. Most of the vegetative parts contains stored food and buds.
(d) Diagram 6.4 shows a piece of wire tied tightly around a tree trunk.This has a negative effect on the growth of the tree after many years.
(i) Suggest one way to avoid the negative effect on the growth of this tree.
Remove the piece of wire and replace it with a nylon string
(ii) Give one reason for the answer in 6(d)(i)
The phloem and the vascular bundles are damaged due to the wires being tied tightly around the tree trunk.Thus, a bulging and protruding part is formed above the upper part of the wire after many years.
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