To investigate the water pollution level of the water samples from three stations of a river

border-width: medium 1pt 1pt medium; border-style: none solid solid none; height: 13.75pt;" valign="top" width="540">

Manipulated : Types of water sample

border-width: medium 1pt 1pt medium; border-style: none solid solid none; height: 13.75pt;" valign="top" width="540">

Responding : Time taken for methylene blue to turn colourless.

border-width: medium 1pt 1pt medium; border-style: none solid solid none; height: 13.75pt;" valign="top" width="540">

Constant : Volume of water samples, volume of methylene blue solution

border-width: medium 1pt 1pt medium; border-style: none solid solid none; height: 13.75pt;" valign="top" width="540">

Apparatus (A)

Reagent bottles, bottle stoppers, a syringe, a stopwatch, beakers.

Materials (M)

0.1% methylene blue solution, water samples from the 3 stations, distilled water.

Objective	To investigate the water pollution level of water samples from 3 stations of the river.
Problem statement	What is the level of pollution for the water samples from the 3 stations of the river?
Hypothesis	Water near the housing area is the most polluted followed by mouth of river and source of the river.
Variables
Apparatus and materials
Technique	Record the time taken for the methylene blue solution to turn colourless using a stopwatch.
Procedure	1. Collect water samples from different sources of the river. 2. Label the reagent bottles, Station 1 : source of the river, Station 2 : near a housing area, Station 3 : mouth of the river 3. Collect samples of river water from 3 different stations. 4. Fill the reagent bottles with 100 ml of water samples collected. 5. Place all the bottles in a dark cupboard. 6. Use a syringe to add 1ml of 0.1 % the methylene blue solution to the based of each water sample. 7. Record the time taken for the methylene blue solution to turn colourless.
	Precaution 1. Close the reagent bottle with a stopper immediately after adding the methylene blue solution. 2. The contents of the bottles cannot be shaken.
Recording data/ result	Station Water sample Time taken for methylene blue solution to decolourise (minit) 1 Source of the river 2 Near a housing area 3 Mouth of the river
Conclusion	Water near the housing area is the most polluted followed by mouth of river and source of river. Hypothesis is accepted.

To determine the effect of drinking different volumes of water on the volume of urine released.

1.Problem Statement:

What is the effect of drinking different volumes water on the volume of urine released?

2.Aim:

To determine the effect of drinking different volume of water on the volume of urine released.

3.Variables:

Manipulated variable : volume of water intake

Responding variable : volume of urine released

Fixed variable : same student/same environment/ time

4.Hypothesis:

The higher the volume of water intake, the higher the volume of urine released.

5.Materials : Boy/girl/student, water

Apparatus : Beakers, glass/cup/mug, measuring cylinder, stop watch

6.Technique:

Measure and record the volume of urine released (after a fixed hour of consuming water) by using a measuring cylinder.

7.Procedure:

1.	A student (Sample A) is chosen and instructed to empty his bladder before the start of the experiment
2.	Measure 200ml of water and put it into the mug/cup/glass.
3	A student (Sample A) is given 200ml of water to drink.
4	A stop watch is started immediately after consuming the water.
5	During the experiment, he is kept in (any fixed suitable room) within 2 hours (any suitable time range).
6	He is instructed not to eat or perform any vigorous physical activities (within the given time).
7	After 2 hour, the stop watch is stopped and he is asked to empty his bladder.
8	The volume of urine collected is measured and recorded.
9	Steps 2 – 8 is repeated for different amount of water drank (400 ml, 600ml, 800ml).
12	The whole experiment is repeated using 2 different students to get a more accurate result.
13	Dispose the measured urine properly
14	Measure and record data collected into a table. Graph of urine output against the water intake is plotted.
15	Precaution : Student is instructed not to eat or perform any vigorous physical activities during the experiment.

8. Results/ data:

Volume of water intake (ml)	Volume of urine released (ml)
	Student A	Student B	Student C	Average
200
400
600
800

9.Conclusion:
The higher the volume of water intake, the higher the volume of urine released. Hypothesis is accepted.

TO ALL FORM 5 STUDENTS OF SMK (P) RAJA ZARINA, PELABUHAN KLANG,
HERE'S ME WISHING ALL OF YOU THE VERY BEST IN YOUR COMING SPM EXAMS.

"When one door closes another door opens; but we so often look so long and so regretfully upon the closed door, that we do not see the ones which open for us."

~ Alexander Graham Bell

2010 Biology Trial Paper 3, Question 2

Design an experiment to determine the effect of carbon dioxide concentration on the rate of photosynthesis.

Answer

Aim/objective:
To determine the effect of carbon dioxide concentration on the rate of photosynthesis.

Problem statement :
What is the effect of carbon dioxide concentration on the rate of photosynthesis?

Hypothesis
When the concentration of carbon dioxide increases, the rate of photosynthesis also increases until the rate becomes constant.

Variables
Manipulated : Concentration of carbon dioxide
Responding : The rate of photosynthesis// The number of bubble released per minute
Constant : Light intensity, temperature/ Size of plant

Apparatus and materials :
Materials : Elodea/Hydrilla , different concentration of sodium bicarbonate, distilled water
Apparatus : Beaker, boiling tube, clip, table lamp, filter funnel

Technique :
Count and record the number of bubbles produced / released in 20 minutes using a stopwatch .

Procedure :
1.Diagram of experimental setup with at least 5 functional labels.
2.Fill a boiling tube with 150 ml of 1% sodium hydrogen carbonate solution.
3.Fix a paper clip / plasticine to a sprig of aquatic / Hydrilla sp. plant.
4.Submerge / put the aquatic plant into the boiling tube containing 1% sodium hydrogen carbonate solution.
5.Put the boiling tube into a water bath at room temperature (20-30^oC).
6.Place the boiling tube at distance of 50 cm from a lighted bulb.
7.Put aside the boiling tube for 5 minute (for the aquatic plant to adjust).
8.Start the stopwatch.
9.Count the number of bubbles release in 20 minutes.
10.Record the result is a table.
11.Repeat steps 2 until 10 using 2%, 3% and 4% of sodium hydrogen carbonate solutions.
12.Calculate the rate of photosynthesis.
(Rate of photosynthesis = Number of bubbles/time)
13.Precaution : Count the bubbles only after the rate becomes constant.

Data
Include the following titles with units:
-Concentration of sodium hydrogen carbonates solution (%)
-Number of bubbles released in 20 minutes
-Rate of photosynthesis (number / minute)

Conclusion:
When the concentration of carbon dioxide increases, the rate of photosynthesis also increases until the rate becomes constant. Hypothesis is accepted.

BIOLOGY PAPER 3 (2003-2009)

2003
Q1. To study the effect of camouflage on a predator-prey relationship
[Chapter 8]
Q2. To study the relationship between the concentration of CO₂ and the rate of photosynthesis [Chapter 6]

2004
Q1.To determine the % of vitamin C in fruit juices using DCPIP solution [Chapter 6]
Q2.To estimate the size of the bird population. [Chapter 8]

2005
Q1.To determine and compare the energy content in white bread and peanuts [Chapter 6]
Q2.To determine the concentration of the solution which will maintain the mass of plant tissues.[Chapter 3]

2006
Q1. To study the effect of concentration of albumen suspension on the rate of reaction of pepsin enzyme [Chapter 4]
Q2. To determine concentration of sucrose which is isotonic to cell sap of mango[Chapter 3]

2007
Q1.To study the effect of light intensity on the rate of photosynthesis of a Hydrilla sp. [Chapter 6]
Q2.To study the effect of temperature on the rate of anaerobic respiration in yeast [Chapter 7]

2008
Q1.To investigate the effect of light intensity on the population distribution of Pleurococcus sp. [Chapter 8]
Q2.To study the size of molecules that can diffuse through a semi permeable membrane [Chapter 3]

2009
Q1.To study the effect of light intensity on the rate of photosynthesis. [Chapter 6]
Q2.To study the effect of temperature on the rate of enzyme reaction. [Chapter 4]

2010
Q1. To investigate the effect of different duration of activity on the percentage of carbon dioxide in exhaled air.[Chapter 7]
Q2. To study the effect of interspecific competition between maize and paddy plants on their growth.[Chapter 8]

2007 Biology Paper 3-Question 2

Anaerobic respiration is the process of releasing energy from the breakdown of glucose in the absence of oxygen. Yeast can carry out anaerobic respiration in a glucose solution.

Glucose ---> Ethanol + Carbon dioxide + Energy

The rate of anaerobic respiration is affected by several factors such as temperature, pH values and nutrients.

Based on the above information and equation, design a laboratory experiment to investigate the effect of temperature on the rate of anaerobic respiration in yeast.

The planning of your experiment must include the following aspects:

§ Problem statement

§ Aim of investigation

§ Hypothesis

§ Variables

§ List of apparatus and materials

§ Technique used

§ Experimental procedure or method

§ Presentation of data

§ Conclusion

ANSWER

:1. Aim of investigation

To investigate the effect of temperature on the rate of anaerobic respiration in yeast.

2. Problem statement

What is the effect of temperature on the rate of anaerobic respiration (in yeast)?

3. Hypothesis

The higher the temperature, the higher the rate of anaerobic respiration (in yeast).

4. Variables

Manipulated variable: Temperature

Responding variable: Rate of anaerobic respiration//No of bubbles released//Time taken for lime water to turn chalky

Fixed variable: Volume/conc. of yeast suspension/glucose/pH/Time taken

5. Apparatus:

Boiling tube, Manometer/Capillary tube, Water bath//Beaker + thermometer,

Stopwatch, Marker/thread, Rubber stopper, Ruler, Rubber tubing, Retort stand, measuring cylinder

Material :

Yeast suspension / Yeast, Glucose solution, Paraffin oil (Yeast & Glucose – must have)

6. Technique

Using a ruler to record the change in height of the colored liquid/Record the number of bubbles released (after 10 minutes) using a stopwatch

//Calculating the rate of anaerobic respiration (in yeast) by using the formula :

Number of bubbles / Change in height

Time taken

//Take and record the time taken for the lime water to turn chalky using a stopwatch.

7. Procedure :

1. Set up the apparatus as shown in diagram.

2. Place the boiling tube with 15 cm³ of glucose solution in a beaker at 20^oC for 5 minutes.

3. Add 15 cm³ of yeast suspension into the boiling tube.

4. Mark the initial height of coloured liquid in manometer.

5. Start the stopwatch and mark the level of coloured liquid in the manometer after 10 minutes.

6. Record all data in a table.

7. Repeat step l, 3, 4, 5 and 6 by placing the boiling tubes in a water bath at temperatures of 30^oC, 40^oC and 50^oC.

8. Make sure all the joints of the apparatus are air tight //Repeat the experiment for each temperature to get average readings.

9. Plot a graph of rate of anaerobic respiration in yeast against temperature.

Precaution :

1. Ensure the temperature is stablised at the fixed temperature before taking the reading if the height of the coloured liquid//counting the number of bubbles released.

2. Make sure all the joints of the apparatus are air tight //Repeat the experiment for each temperature to get average readings.

8. Result: Draw a table

9. Conclusion:

Hypothesis is accepted. The higher the temperature, the higher the rate of anaerobic respiration in yeast.