12. Expel the potassium hydroxide solution leaving about 2-3 mm from the end of the tube
13. Repeat step 9 using potassium pyrogallate solution (potassium pyrogallate absorbs oxygen from the air column)
14. Repeat steps 6 and 7 .Record the length of the air column as r cm 15. Based on the results ,calculate the percentage of carbon dioxide and
oxygen in the sample of inhaled air column using formula 16. Repeat steps 1 -17 using a sample of exhaled air
17. Compare the percentage of carbon dioxide in inhaled and exhaled air 18. Compare the percentage of oxygen in inhaled and exhaled air
Presentation data Data for inhaled air
Length of inhaled air column at the
beginning experiment P
Length of inhaled air column after treating with potassium hydroxide solution
Q
Length of inhaled air column after treating with potassium pyrogallate solution
R
Length of CO2 column in inhaled air (p-q)cm Length of O2 column in inhaled air (q-r)cm Percentage of CO2 in inhaled air p-qcm x 100%
p cm Percentage of O2 in inhaled air q-rcm x 100
p cm
Data for exhaled air
Length of inhaled air column at the
beginning experiment X
Length of inhaled air column after treating with potassium hydroxide solution
Y
Length of inhaled air column after treating with potassium pyrogallate solution
Z
Length of CO2 column in inhaled air (x-y)cm Length of O2 column in inhaled air (y-z)cm Percentage of CO2 in inhaled air (x-y)cm x 100%
X cm Percentage of O2 in inhaled air (y-z)cm x 100%
X cm
15.TO STUDY HOW POPULATION SIZE OF SPECIES MIMOSA PUDICA AND IMPERATA CYLINDRICA CAN BE DETERMINED IN YOUR SCHOOL FIELD Problem statement
What is the population size of mimosa pudica and imperata cylindrica in the school field?
Hypothesis
The population size of species mimosa pudica plant is higher than species imeprata cylindrica in the school field
Variables
MV : type of plant RV : population size CV : quadrat size
Materials and apparatus
Plant species Mimosa Pudica and imperata cylindrica ,plastic quadrat,marker pen,A4 paper,graph paper
Procedure
1. School field was chosen as the field study 2. Quadrats size 1mx1m was used
3. Two plants species mimosa pudica and imperata cylindrica was identified 4. The quadrats were thrown at random in the school field
5. The area of coverage each plant species were counted
6. If more than half of the squares in the quadrat are covered ,the area of plant species will be counted.the area is not counted if only less than half is
covered
7. Steps 5 to 7 was repeated for nine quadrats
8. The area covered by plant species studied in each quadrat were recorded and tabulated in a table
9. The percentage coverage of plant species were calculated by using this formula :
percentage of coverage = total are covered plant species In all quadrats X 100
Total number of quadrants x area of quadrat Presentation of data
Plant Number of plant species in the quadrat Total number of
Percentag e
specie s
plant species(m2 )
coverage area (%)
1 2 3 4 5 6 7 8 9 10
19.TO INVESTIGATE THE WATER POLUTION LEVEL AND BOD VALUE AT THE STATION A,B, AND C
Problem statement
Which sources of water sample A,B and C will be more polluted and give the higher BOD value?
Hypothesis
Water sample C are the most polluted and have the highest BOD value compare to water sample A and B
Variable
MV : type water samples
RV : water pollution level and BOD values CV : volume of water sample
Apparatus and materials
Reagents bottles with stoppers,syringe,cupboard,stopwatch,label paper, measuring cylinder, beaker, water sources from station A,B and C,methylene blue solution Procedure
1. 200ml water samples from A,B and C sources are collected 2. 3 bottles of reagent are labeled as A,B, and X respectively
3. 100ml of water samples at A were measured by using measuring cylinder are being put into reagent bottle
4. 1ml of methylene blue solution 0.1% solution was added to the base of each water samples using a syringe
5. The bottles are closed quickly and the contents are not to be shaken 6. Steps 1 to 5 were repeated by using water source from station B and C 7. All the bottles are placed in a cupboard and the stopwatch is started 8. The bottle are examined from time to time
9. The time taken for methylene to decolourise is recorded for all the water samples
10.The results are recorded in a table Presentation of data
Reagent bottles Water samples
(100ml) Time taken to decolourise methylene blue
(hour)
BOD value and pollution level
(unit) A
B C
16.TO STUDY THE EFFECT OF LIGHT INTENSITY ON THE POPULATION GROWTH RATE OF LEMNA MINOR
Problem statement
What is the effect of light intensity on the growth rate of lemna minor?
Hypothesis
The higher the light intensity the higher the growth rate of lemna minor at the end of experiment
Variables
MV : light intensity
RV : the growth rate of lemna minor CV : initial number of lemna minor Apparatus and materials
Lemna minor,pond water,light bulb(5,40,80 watts),beaker,ruler,measuring cylinder,waterproof paint
Procedure
1. Three beakers are prepared and filled with 500ml of water in each beaker 2. The beakers are labeled as A,B and C with waterproof paint
3. 5 lemna minor are put into each baker
4. Each beaker is placed at 30cm from the lamps with different light intensities ,that is 5 watts ,40 watts, and 80 watts respectively 5. All the beakers are placed in area of the same temperature 6. Change the water in each beaker every 3 days
7. After 7 days,the number of lemna minor in each beaker is counted and recorded
8. The growth rate of lemna minor is calculated by using formula:
The number of lemna minor Time taken(day)
9. The result are recorded in a table Presentation of data
Light intensity
(watts) Number of lemna The growth rate of
lemna minor
Beginning end
5 5
40 5
80 5
17.TO STUDY THE EFFECT OF PH ON THE POPULATION GROWTH OF LEMNA MINOR IN THIS LABORATORY
Problem statement
Does the changes in pH effects the growth rate of lemna minor?
Hypothesis
The growth rate of lemna minor is higher in neutral medium Variables
MV : the changes in pH
RV : the growth rate of lemna minor
CV : numberof lemna minor in the beginning of experiment Apparatus and materials
Lemna minor,pond water,0.1M hydrochloric acid ,0.1M sodium hyroxide,distilled water,beaker,waterproof paint,measuring cylinder and dropper
Procedure
1. Three beakers are prepared and filled with 500ml of pond water in each beaker
2. The beaker are labeled A,B, and C with waterproof paint
3. Bu using measuring cylinder,10ml of 0.1M of hydrochloric acid is measured and poured into beaker A,10ml of 0.1M sodium hydroxide solution is
measured and poured into beaker B and 10ml of distilled water is measured and poured into beaker C
4. 20 numbers of lemna minor are put into each beaker
5. Each beaker is placed in an area of distributed light and temperature 6. After 5 days,the number of lemna minor is counted in each beaker 7. The growth rate of lemna minor is calculated by using formula 8. The result are recorded in a table
Presentation of data
Beaker Condition of pH Number of lemna minor The growth rate of lemna
minor(day)
beginning ending
A 0.1M of hydrochloric acid(acidic)
B 0.1M sodium hydroxide(alkaline) C distilled
water(neutral)
20.TO DETERMINE THE NUMBER OF SOLID POLLUTANTS IN THE AIR OF DIFFERENT ENVIRONMENT
Problem statement
Which place will produce the largest number of fine particle in the air?
Hypothesis
The number of solid particles in school car park is higher than air sample in air conditional room,classroom and school canteen
Variables
MV : location where glass slide is placed RV : number of solid particles
CV : time exposure
Apparatus and materials
Glass slide,cellophone tape,light miscroscope,petri dish,ruler,places of study,fine particles
Procedure
1. 4 slides are prepared and labeled them A,B,C and D
2. 5cm of cellophane tape is sticked on each slide with the sticky surface facing outward
3. The slide A is placed at school park 4. Leave the slide undisturbed for a week
5. After one week,collect a slide view under light microscope under low power 6. Repeat experiment for slide B at conditioned room,slide C at classroom and
slide D at school canteen
7. The number of solid pollutions is recorded Presentation of data
Glass slide Place where slide is Number of fine particles
located as seen under microscope (unit)
A Air conditioned room
B Classroom
C School canteen
D School car park
21.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 : TSA/V
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 1cm3,8cm3,27cm3, and 64cm3
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 Percentage of coloured area %
Time taken(Min) Presentation of data
Size of cubes(cm3) Percentage of coloured
area (%) Rate of diffusion of potato cube (%/min)
1 8 27 64
22.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,ruber 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
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)
23.TO STUDY THE EFFECT OF LIGHT INTENSITY ON THE RATE OF TRANSPIRATION
Problem statement
Is the light increasing the rate of 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 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 2. The cut plant is then fixed onto a photometer and the joint between
the plant and the photometer are sealed using a Vaseline to make the airtight
3. The laboratory curtains and doors are pulled and closed so that outside lightning will not effect 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
24.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
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 mae 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 ermoving 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
Prresentation of data Speed of
fan Time taken for the air bubble to move from point X to Y
(minutes) Rate of
transpiratio n (cm/min) First reading Second
reading
25.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 Yat 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 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
26.TO INESTIGATE THE EFFECT OF AIR HUMIDITY ON THE RATE OF TRANSPIRATION
Problem statement
Does humidity of air effect the rate of temperature?
Hypothesis
When the air humidity surrounding the plant is high,the rate of transpiration is low Variable
MV : humidity of air RV : rate of transpiration CV : temperature
Apparatus and materials
Photometer,stopwatch,cutter,beaker,meter ruler,a basin of water,marker,a leafy shoot,water,vaseline,dry cloth,anhydrous calcium chloride,transparent bag 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 bubble are trapped in the apparatus
4. A finger is placed over the open end of the capillary tube.the apparatus is removedfrom the basin
5. The open end of the capillary tube is placed under 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 tissue paper.some vaseline is smeared around the rubber tubing to make sure the apparatus airtight
7. The capillary tube is lifted just clear above the water reservoir .the rubber
7. The capillary tube is lifted just clear above the water reservoir .the rubber