5th

Name: Geofrey Jinuin

Class: 3 Melati

Problem Statement

: Does light effect the rate of transpiration?

Hypothesis

:Light increases the rate of transpiration.

Variable

a)fixed

:Size and types of plant, humidity, wind, temperature and time.

b)manipulated

: Presence of light.

c)responding

: Difference in weight of the apparatus and rate of transpiration.

Apparatus

:Electronic balance, conical flask, clock or watch and source of light such as sunlight or lamp.

Materials

:Young balsam plant, water, cotton wool and oil.

Procedure. 1. 2. 3. 4. 5. 6.

Set up the apparatus as shown. Weight the apparatus and record. The apparatus on the table in bright room Pace the apparatus in a cupboard or the same room. After 2 hours, observe and record. Tabulate your results and calculate the rate of transpiration.

Results. *Condition *Mass of apparatus at this beginning experiment (g) *Mass of apparatus at the end of experiment. *Rate of transpiration (g/min) Presence of light

Presence of light

163

g

158.4g

160

g

158.7g

163-160.6

=0.03 (g/min)

90

158.7-158.7

= 0.00 (g/min)

90

Experiment B Problem Statement

: Does Humidity affect the rate of transpiration?

Hypothesis

:Higher humidity decreases the rate of transpiration

Variable

a)fixed

:Size and types of plant, light intensity, wind, temperature and time.

b)manipulated

: humidity

c)responding

: Difference in weight of the apparatus and rate of transpiration.

Apparatus

:Electronic balance, Plastic bag, conical flask and clock or watch.

Materials

:Young balsam plant, anhydrous calcium, water, cotton wool and oil.

Procedure. 1. 2. 3. 4. 5. 6.

Set up the apparatus as shown. Weight the apparatus and record. Leave the apparatus on the table. Repeat step 1 to 3 but cover the plant with a plastic bag as shown. After 2 hours, reweigh the two sets of apparatus and record. Tabulate your results and calculate the rate of transpiration of the plant.

Results. Higher humidity

lever umidity

164.7

g

189.7

g

164.5

g

189

g

164.7-164.5

=0.02

189.7-189

90

= 0.02

90

Experiment C Problem Statement

: Does wind effect the rate of transpiration?

Hypothesis

:The presence of wind increases the rate of transpiration.

Variable

a)fixed time.

:Size and types of plant, humidity, light intensity, temperature and

b)manipulated

: Presence of wind.

c)responding

: Difference in weight of the apparatus and rate of transpiration.

Apparatus

:Electronic balance, conical flask, clock or watch and fan. or lamp.

Materials

:Young balsam plant, water, cotton wool and oil.

Procedure. 1. 2. 3. 4.

Set up the apparatus as shown. Weight the apparatus and record. Leave the apparatus on the table. Switch off the fan. Repeat step 1 to 3 but cover the plant with a plastic bag as shown. 7. After 2 hours, reweigh the two sets of apparatus and record. 5. Tabulate your results and calculate the rate of transpiration of the plant. Results. Presence of wind

Presence of light

168.9

g

175.7

g

168.2

g

174.5

g

168.9-168.2

=0.07

90

175.7-174.5

= 0.02

90

Questions 1a) Name another factor that affects the rate of transpiration in plants. –

Temperature

1b) Plan and carry out the experiment to investigate how it affect rate of transpiration. – – – – – –

– –

A conical flask is filled with 200cm of water A balsam plant is putted inside the conical flask. A layer of oil is poured over the water surface in the conical flask. A layer of oil is poured over the water surface in the conical flask. The conical flask content is weighed. The initial reading of the electronic balance is recorded in a table. The apparatus is left in the science laboratory . Step 1 to 5 are repeated and the apparatus is placed in a hot place

2. What procedure can be taken to ensure the result of the experiment are accurate? 1. 2. 3. 4.

Set up the apparatus as shown. Weight the apparatus and record. Leave the apparatus on the table. Switch off the fan. Repeat step 1 to 3 but cover the plant with a plastic bag as shown. 5. After 2 hours, reweigh the two sets of apparatus and record. 6. Tabulate your results and calculate the rate of transpiration of the plant.

What are the conclusion for all the epidermis carried out? –

Plant release water from it leaves through transpiration.

Conclusion: –

The rate of transpiration is affected by the temperature, light intensity air movement and air humidity.