This document describes the procedures for several experiments investigating biological processes: 1. An experiment to determine the concentration of sucrose solution isotonic to potato cell sap by measuring changes in length of potato strips in different sucrose concentrations. 2. An experiment examining the effect of albumen concentration on the rate of enzyme reaction by pepsin by measuring the time for solutions to turn colorless. 3. An experiment measuring the energy content of different foods like cashew nuts, peanuts, and bread by recording the increase in temperature of water heated by samples. 4. An experiment determining the vitamin C concentration in different fruit juices like guava, orange, and pineapple by measuring the volume needed to decolorize a

1. TO DETERMINE THE CONCENTRATION OF SUCROSE SOLUTION WHICH IS
ISOTONIC TO THE CELL SAP OF POTATO STRIP
Problem statement
What is the concentration of the sucrose solution that will maintain the length of potato
strip?
Hypothesis
As the sucrose solution reach certain concentration (isotonic to the cell sap),there is no
changes in the length of potato strip
Variables
MV : the concentration of the sucrose solution
RV : change in length of potato strip
FV : initial length of potato strip
Apparatus & material
Cork borer, test tubes, stopwatch, ruler, potatoes, various concentration of sucrose
solution, filter paper
Procedure:
1.Six test tube are labelled P,Q,R,S,T and U
2.Test tube P is filled with 10ml distilled water, test tube Q is filled with 10ml sucrose
solution O.1M,test tube R is filled with 10ml sucrose solution 0.2M,test tube S is filled
with 10ml sucrose solution 0.3M,test tube T is filled with 10ml sucrose solution 0.4M and
test tubes U is filled with 10ml sucrose solution 0.5M
3.The cork borer is pushed into the potato and the potato strip is obtained by pushing it
out of the cork borer using a glass rod
4.The potato strips are cut to the exact length of 5 cm.
5.One potato cylinder is placed in each labeled test tubes for 30 minutes.
6.After 30minutes,the potato strips are removed from the test tube and gently wiped
with filter paper
7.The final length of the potato strips are measured and record using a ruler
8.The final length of the potato strips are recorded in a result table
9. A graph pf the concentration of sucrose solution against the change in the length is
plotted
Presentation
Test
tube
Concentration
of sucrose
solution(M)
Length
Initial(cm) Final(cm)
Change in
length(cm)

2. P 0 5
Q 0.1 5
R 0.2 5
S 0.3 5
T 0.4 5
U 0.5 5
TO INVESTIGATE THE EFFECTS OF ALBUMEN CONCETRATION ON THE ENZYME
PEPSIN REACTION
Problem statement
What is the effect of different albumen concentration on the rate of enzyme reaction?
Hypothesis
The higher the albumen concentration,the higher the rate of enzyme reaction
Variables
MV : the concentration of albumen solution
RV : rate of enzyme reaction
CV : the volume of albumen solution
Apparatus and Materials
Albumen solution (1%,2%,3%,4%),1% pepsin solution, pipette/measuring cylinder, HCL,
water bath, thermometer, stopwatch
Procedure
1. 5ml of 1% albumen solution is poured into a test tube using a pipette.The test tube is
labeled P.
2. 1 ml of HCL acid is poured into the same test tube using another pipette
3. 1 ml of 5% pepsin is poured into the same test tube using another pipette.The mixture
is shaken well.
4. The test tube is placed in the beaker containing 300 ml of water at 37oC.A
thermometer is placed in the beaker to check the temperature.
5. The stopwatch is started
6. The mixture is observed and the time taken for the solution to turn colourless is taken
using a stopwatch and recorded in a table.
7. Steps 1 to 6 are repeated twice to get an average result
8. Steps 1 to 7 are repeated, replacing the 1% albumen solution with 2%,3% and 4%
albumen solution respectively.
9. All data are recorded in a table and a graph of the rate of enzme reaction against the
albumen concentrated is plotted
Presentation of data

3. Concentration
of albumen
solution (%)
Time taken for the mixture to
turn colourless (min)
The
rate of
enzyme
reaction
(min-1
)1 2 3 average
1
2
3
4
TO DETERMINE THE ENERGY CONTENT IN THE SAMPLE OF FOOD
Problem statement
Does the final water temperature reading for cashew nut is higher than peanut and white
bread?
Hypothesis
The final temperature reading/energy value for cashew is higher than peanut and white
bread
Variables
MV : type of food
RV : the energy content
CV : volume of distilled water
Materials and apparatus
Cashew nut, peanut, white bread, distilled water, boiling tubes, plasticine, pin,
thermometer, Bunsen burner and wire gauze, stopwatch, retort stand and clamp
Procedure
1. Weigh the white bread and record its weight
2. Fill a boiling tube with 20ml distilled water
3. Clamp the boiling tube to the retort stand
4. Record the initial temperature of the water in the boiling tube
5. Spike the white bread firmly at the end of the pin which is mounted on some plasticine
6. Ignite the white bread by holding it in the flame of a bunsen burner.then, immediately
place it beneath the boiling tube to heat the water
7. Stir the water gently with the thermometer
8. Record the initial temperature, that is the highest temperature reached as soon as the
peanut has stopped burning using thermometer.
9. Calculate the energy value of the peanut using the formula below [show energy value

4. formula]
10. Tabulate the results in table below
11. Steps 1 to 9 are repeated by using different food sample such as peanut and cashew
nut
Presentation of data
Food
sample
Temperature 0
C
Energy
valueInitial Final
Increase in
temperature
White
bread
Peanut
Cashew
nut
TO DETERMINE THE CONCENTRATION OF VITAMIN C CONTENT IN THE
SAMPLE OF FRUIT JUICES
Problem statement
What is the sample of fruit juices that contains a higher concentration of vitamin C?
Hypothesis
Guava juice contains a higher concentration of vitamin C compared to orange Juice and
pineapple juice
Variables
MV : type of fruit juice
RV : concentration of vitamin C
CV : volume of DCPIP solution
Apparatus and materials
Boiling tube, a syringe,a syringe with needles ,beaker, gauze cloth and a knife ,DCPIP
solution,0.1% ascorbic acid solution .freshly prepared guava juice, pineapple juice and
orange juice
Procedure
1. Label four boiling tube as A, B, C, and D
2. Place 1ml of DCPIP solution in each boiling tube
3. Fill a syringe with 5ml of ascorbic acid solution
4. Immerse the needle of the syringe in the DCPIP solution drop-by-drop

5. 5. Do not shake the tube vigorously
6. Record the volume of ascorbic acid solution used to turn the DCPIP solution colourless
using a syringe
7. Repeat steps 22 to 7 using Lime Juice, pineapple juice and papaya juice
8. Calculate the percentage and concentration of vitamin C in these three types of fruit
juice using the formula below [ shows percentage of vitamin C and Concentration of
vitamin C formula]
Presentation of data
Solution
Volume of
fruit juice
needed to
decolourize
1ml of
DCPIP
solution
(ml)
Percentage
of vitamin
C In fruit
juice (%)
Vitamin C
concentration
in fruit juice
(mg/cm)
TO DETERMINE THE EFFECT OF LIGHT INTENSITY ON THE RATE OF
PHOTOSYNTHESIS
Problem statement
What is the effect of light intensity on the rate of photosynthesis?
Hypothesis
The higher the light intensity ,the higher the rate of photosynthesis until it reaches
limiting value
Variables
MV : light intensity
RV : rate of photosynthesis
CV : The temperature
Apparatus and materials
Hydrilla Sp.,0.3% sodium hydrogen carbonate solution, beaker, thermometer, test

6. tube,stopwatch,60W electric bulb , measuring cylinder , retort stand, paper clip, metre
ruler
Procedure
1. A 5cm sprig is cut from a hydrilla sp. Plant using a sharp scalpel
2. The plant is placed with the cut end facing upwards
3. A paper clip is used to weight down the other end of the hydrilla sp. Sprig
4. 10ml of 0.3% sodium hydrogen carbonate solution is poured in a boiling tube
5. The boiling tube with plant is placed in a water bath with the temperature maintained
at 280C
6. A 60watt bulb is placed at a distance of 50cm from the plant
7. When the rate of bubbles given out is constant ,the number of bubbles released for 5
minutes is recorded using a stopwatch
8. The steps are repeated by placing the apparatus at distance 40cm,30cm,20cm and 10cm
from the light source.
9. The results are recorded and the rate of photosynthesis is calculated by using a
formula:[rate of photosynthesis formula]
Presentation of data
Distance
of light
source
(cm)
Number
of
bubbles
released
in 5
minutes
Rate of
photosynthesis
(number of
bubble
/minute)
50
40
30
20
10
TO INVESTIGATE OF TEMPERATURE ON THE RATE OF ANAEROBIC
RESPIRATION IN YEAST
Problem statement
What is the effect of temperature on the rate anaerobic respiration in yeast?
Hypothesis
The increase the temperature,the increase the rate of anaerobic respiration in yeast

7. Variables
MV : temperature
RV : the rate of anaerobic respiration
CV : volume/concentration of yeast
Apparatus and materials
Yeast solution, glucose solution, coloured liquid, paraffin oil, manometer tube, measuring
cylinder , rubber tubing, clip ,glass tube, ruler, boiling tube, water bath, stopwatch,
marker pen, rubber stopper, thermometer , beaker, retort stand
Procedure
1.Filled the boiling tube with 15 ml yeast suspension.
2. Then the boiling tube is added with 10ml 5% glucose solution
3. The boiling is filled with paraffin oil
4. The apparatus is joined to a rubber stopper with glass tube, rubber tubing and the
manometer
5. The apparatus is placed to a retort stand
6. Mark and record the initial height of the coloured liquid in the manometer with a
marker pen
7. Then, placed the boiling tube in water bath at 200C
8. Start the stopwatch and mark the level of coloured liquid in the manometer (after 10
minutes)
9. Record the final height of the coloured liquid in the manometer using a ruler
10. Repeat the experiment by placing the boiling tube in water baths at 300C, 400C and
500C
11. Make sure all the joints of the apparatus are air-tight
12. Calculate and record the rate of anaerobic respiration in yeast by using a formula
13. The results are tabulated in a table
Presentation of data
Temperature
The height of
coloured liquid
in
manometer(cm)
Rate of
anaerobic
in yeast
(cm/min)
(C0
) initial final
20
30
40
50

8. THE EFFECT OF CONCENTRATION OF GLUCOSE ON THE RATE OF ANAEROBIC
RESPIRATION IN YEAST
Problem statement
What is the effect of concentration of glucose on the rate of anaerobic respiration in
yeast?
Hypothesis
The higher the concentration of glucose the higher the rate of anaerobic respiration in
yeast
Variables
MV : concentration of glucose
RV : The rate of anaerobic respiration
CV : Concentration of yeast solution
Apparatus and materials
Yeast solution, glucose solution, Vaseline, coloured liquid, paraffin oil, manometer tube,
measuring cylinder , rubber tubing, clip ,glass tube, ruler, boiling tube, water bath,
stopwatch, marker pen, rubber stopper, thermometer , beaker, retort stand
Procedure
1. Filled the boiling tube with yeast suspension.
2. Then the boiling tube is added with 10ml 5% glucose solution
3. Glucose solution is heated to remove dissolved oxygen. The solution is left to cool
4. The boiling is filled with paraffin oil
5. The apparatus is joined to a rubber stopper with glass tube, rubber tubing and the
manometer
6. Vaseline is used to make sure all the joints is airtight
7. The apparatus is placed to a retort stand
8. Mark and record the initial height of the coloured liquid in the manometer with a
marker pen
9. Start the stopwatch and mark the level of coloured liquid in the manometer (after 10
minutes)
10. Record the final height of the coloured liquid in the manometer using a ruler
11. Repeat the experiment by 10% and 30% glucose solution
12. Calculate and record the rate of anaerobic respiration in yeast by using a formula
13.The results are tabulated in a table
Presentation of data

9. Concentration
of glucose
(%)
The height
of coloured
liquid in the
manometer
(cm)
Rate of anaerobic
respiration(cm/min)
initial final
5
10
20
TO DETERMINE THE EFFECT OF TOTAL SURFACE AREA TO VOLUME(TSA/V)
RATIO TOWARDS THE RATE OF DIFFUSION OF SUBTANCES BY USING POTATO
Problem statement
How does the TSA/V ration effect the rate of diffusion of the substance?
Hypothesis
As the TSA/V ratio increases the rate of diffusion of the substances increases
Variables
MV : Total surface area per volume
RV : rate of diffusion
CV : concentration of coloured water
Apparatus and materials
Coloured water, potato, filter paper, knife, blade, white tiles, forceps, stopwatch, grided
transparency sheet, beaker
Procedure
1. Potato is cut into cubes which is 1 , 8 , 27 , and 64
2. Each potato cubes is placed in a beaker containing coloured water for 20minutes
3. After 20minutes the potato cubes are cut into two halves
4. The outer surface of the potato cubes are dried using filter paper
5. The transparency sheet is placed on the top of cut surface
6. The area that is stained red is drawn and shaded on the gridded transparency
7. Coloured area in each potato cubes is measured by using gridded transparency
8. The percentage of coloured area in each potato cube is calculated and recorded
9. Calculated and recorded the rate of diffusion using a formula
Presentation of data

10. Size of
cubes(cm3
)
Percentage
of
coloured
area (%)
Rate of
diffusion
of
potato
cube
(%/min)
1
8
27
64
TO DETERMINE WETHER THE NUMBER OF LEAVES EFFECTING THE RATE OF
TRANSPIRATION IN PLANTS
Problem statement
Does number of leaves effect the rate of transpiration?
Hypothesis
The higher the number of leaves,the higher the rate of photosynthesis
Variables
MV : number of leaves
RV : rate of transpiration
CV : air movement
Apparatus and materials
Plant shoot with leaves, water, photometer (or capillary tube, ruler, rubber
tube),stopwatch, light bulb, beaker
Procedure
1. A leafy shoot is chosen from a plant. The shoot is cut and is immersed immediately into
a basin of water
2. The shoot is cut 1cm from the bottom of the stem under water. The leaves are removed
from the shoot and 8 leaves is left behind
3. The cut end of the stem is inserted carefully into the rubber tubing of the photometer
under water
4. The apparatus is then set up as shown in diagram .the end of the tube is immersed in a
beaker of water
5. The leaves and the apparatus are wiped dry with a cloth
6. Vaseline is used to ensure no water leakage and the apparatus is air tight
7. An air bubble is introduced in the tube
8. The photometer then placed in an enclosed room with no air movement

11. 9. The shoot is allowed a few minutes to reach a steady state before any readings is taken
10. The stopwatch is activated and the time taken for air bubble travel10cm distance is
recorded
11. The experiment is repeated to obtain two more reading
12. Steps 1 to 11 are repeated by using difference shoot with difference number of leaves
6, 4, 2 and 0.
13. The time taken for air bubble to travel for each shoot is recorded in the following
table using stopwatch
14. Calculate the rate of transpiration by using formula
Presentation of data
Number
of
leaves
Time
taken
(min)
Rate of
transpiration(cm/min)
0
2
4
6
8
TO STUDY THE EFFECT OF LIGHT INTENSITY ON THE RATE OF
TRANSPIRATION
Problem statement
Is the light increasing the rate of transpiration of a plant?
Hypothesis
The higher the light intensity,the higher the rate of transpiration
Variables
MV : distance light sources
RV : rate of transpiration
CV : temperature
Apparatus and materials
Photometer, stopwatch, knife, beaker, fluorescent lamp, meter ruler, balsam plant,
Vaseline, water, tissue
Procedure
1. A suitable balsam plant is selected and is cut using a sharp knife. The cut end is
immediately immersed in a beaker filled with distilled water

12. 2. The cut plant is then fixed onto a photometer and the joint between the plant and the
photometer are sealed using Vaseline to make the airtight
3. The laboratory curtains and doors are pulled and closed so that outside lightning will
not affect the outcome of experiment
4. A 40W fluorescent lamp is set 30cm away from the edge of the photometer with a
meter ruler placed to measure the distance
5. The air bubble in photometer is set to 0cm.the lamp is switched on and the stopwatch is
started when the air bubble cross X mark.
6. The movement of air bubble is observed and the stopwatch is stopped when the bubble
reaches Y mark that is 10cm
7. Record the time taken into a table using stopwatch
8. Step 4 to 7 are repeated ,with the distance of the lamp are put at 40cm,50cm,60cm
away from the photometer.
9. Calculate the rate of transpiration by using a formula
10. All the findings are recorded In a table
Presentation of data
Distance of
lamp from the
edge of
photometer
(cm)
Time taken for
the air bubble
to travel from X
to Y (s)
Rate of
transpiration
(cm/second)
0
40
50
60
TO STUDY THE EFFECT OF AIR MOVEMENT ON THE RATE OF TRANSPIRATION
Problem statement
What are the effect of the different speed of air movement on the rate of transpiration?
Hypothesis
As the speed of the air movement increases, the rate of transpiration increases.
Variables
MV : speed of air movement
RV : Rate of transpiration
CV : the temperature
Apparatus and materials

13. Capillary tube, retort stand, 50ml beaker, basin, scalpel, rubber tubing, tissue paper,
Vaseline, marker pen and stopwatch, ruler, fan, water and plant shoot
Procedure
1. The leafy shoot is immersed In the water and cut using a sharp scalpel
2. The rubber tubing and capillary tube is placed in the basin containing water. The
apparatus is filled with water. The leafy shoot is inserted into the rubber tubing
3. Steps 1-2 is carried out under water to make sure no air bubbles are trapped in the
apparatus
4. A finger is placed over the open the end of the capillary tube. The apparatus is removed
from the basin
5. The open end of the capillary tube is placed under water in the beaker before removing
the finger from the tube
6. The water is dried from the surface of the leaves of the shoot using a tissue paper.
Some Vaseline is smeared around the rubber tubing to make the apparatus airtight
7. The capillary tube is lifted just clear above the water reservoir .the rubber tubing is
squeezed gently to release one drop of water from the capillary tube .the capillary tube is
placed in water
8. The apparatus is supported by a retort stand. A marker pen is used to mark two points,
X and Y at a distance of 5 cm apart
9. The photometer is placed under the table fan with speed 1 .record the time taken (in
minutes) for the air bubble to move from point X to point Y using stopwatch
10. Repeat the experiment twice
11. To reset the photometer, squeeze the rubber tubing so that air bubble escapes into
the beaker of water
12. The above step is repeated to get three readings with the same shoot in under water a
an with speed 2 and respectively
13.The average rate of the rate of transpiration measurement is recorded in the table
using formula
Presentation of data
Speed
of fan
Time taken for the air bubble to move
from point X to Y (minutes) Rate of
transpiration
(cm/min)
First
reading
Second
reading
Third
reading
average
Speed 1
Speed 2
Speed 3

14. TO INVESTIGATE THE EFFECT OF TEMPERATURE ON THE RATE OF
TRANSPIRATION
Problem statement
Does the temperature affect the rate of transpiration of a plant?
Hypothesis
The higher the temperature, the higher the rate of transpiration of a plant
Variables
MV : temperature
RV : the rate of transpiration
CV : air movement
Apparatus and materials
Photometer, stopwatch, cutter, beaker, meter ruler, a basin of water, marker, a leafy
shoot, water, vaseline, dry cloth, thermometer, transparent frame
Procedure
1. The leafy shoot is immersed in the water and cut using a sharp scalpel
2. The rubber tubing and capillary tube is placed in the basin containing water. The
apparatus is filled with water. The leafy shoot is inserted into the rubbing tubing.
3. Steps 1 and 2 is carried out under water to make sure no air bubbles are trapped in the
apparatus
4. A finger is placed over the open end of the capillary tube. The apparatus is removed
from the basin
5. The open end of the capillary tube is placed under water in the beaker before removing
the finger from the tube
6. The water is dried from the surfaces of the leaves of the shoot using tissue paper.
Some Vaseline is smeared around the rubber tubing to make it airtight
7. The capillary tube is lifted just clear above the water reservoir. The rubber tubing is
squeezed gently to release one drop of water from the capillary tube. The capillary tube is
placed in water
8. The apparatus is supported by a retort stand. A marker pen is used to mark two
points ,X and at a distance 5cm apart
9. The non-transparent frame is used to cover the leafy shoot and of the photometer is
placed in the shady place at 300C.the temperature inside the frame is recorded using
stopwatch
10. Record the time taken (in minutes)for the air bubble to move from X to Y using
stopwatch
11. To reset the photometer, squeeze the rubber tubing so that air bubble escapes into

15. the beaker of water
12. The above step is repeated to get the three readings with the same shoot with the
transparent frame to cover the leaf shoot and photometer is placed under the sun at
330C.the temperature inside the frame is recorded using stopwatch
13. The rate of transpiration measurement is recorded in the table by using formula
Presentation of data
temperature
Time taken for the air bubble to move
from X to Y (minute)
Rate of
transpiration(cms-
1
)1 2 3 average
Shady place
300
C
Under the
sun 330
C
TO DETERMINE THE URINE VOLUME RELEASED BY A STUDENT WHO DRINKS
DIFFERENT VOLUME OF MINERAL WATER
Problem statement
What is the effect of water intake of urine output?
Hypothesis
If more water is taken, more urine will be released
Variables
MV : volume of water
RV : volume of urine released
CV : same student
Apparatus and materials
Beakers, cup/mug, measuring cylinder, stopwatch, drinking water, a student
Procedure
1.A student (sample A) is chosen and instructed to empty his bladders before the start of
the experiment
2. 200ml of water is measured and put into the mug
3. A student (sample A) is given 200ml of mineral drinking water drink
4. A stopwatch is started immediately after consuming the water
5.During the experiment, he is kept within 1-2 hours
6. He is instructed not to eat or perform any vigorous physical activities
7. After half an hour, he is asked to empty his bladder
8. The collected urine is kept in a large beaker

16. 9. At the interval of half an hour, until two hours, students empty his bladder
10. After two hours, the total collected urine is measured using measuring cylinder
11. Repeat step 2-9 for different amount of drinking water (400ml, 600ml, 800ml, 1000ml)
12. Step 7 is conducted for four consecutive days in a fixed time and place
13. Dispose the measured urine properly
14. Measure and record the data collected into a table
Presentation of data
Volume of water intake(ml)
Volume of
urine is
produced(ml)
200 400 600 800 1000