3E MODEL

ENGAGE,

EMPOWER,

ENHANCE

SLURP it up!

When plants have more water in their leaves than they need, they get rid of this extra water through a process called transpiration. During transpiration, water evaporates from holes in the surfaces of leaves into the air. As water molecules evaporate from plant leaves, they attract the water molecules still in the plant, helping to pull water up through the stems from the roots.

The combination of transpiration and capillary action delivers the water from the bottom to the top of a plant.

SCIENTIFIC CONCEPT

ENGAGE

White carnation turned blue after

soaking in blue solution

White carnation stalk was placed in the blue solution. After a few minutes, the petals change from white to blue colour.

Question:-

Why does the white carnation turned blue after soaking in the blue solution?

EMPOWER

Planning and Doing Experiment – Observation on rate of

transpiration when different temperature is given.

Set A :

Using 100W

table lamp

Set B : Using

60W table

lamp

EMPOWER

Apparatus and materials

Data logger

2 Humidity sensors

2 Temperature sensors

Plant

Scissors

2 Table lamps of different watts (60W and

100W)

EMPOWER

PROCEDURE

1. The apparatus is set up as shown in the diagram.

2. The temperature and humidity sensors are connected to the data logger, which is in turn is plugged into the PC.

3. The humidity sensor and the temperature sensor are placed on the branch of the plant.

4. Plant A is given a table lamp of 60W while plant B is given a table lamp of 100W.

5. The data logger is set to record at one sample per minute, with a maximum of 1000 samples (i.e. 16 minutes worth of data).

6. The spread sheet is set to show both temperature and humidity. The graph is set to show temperature and humidity.

EMPOWER RESULTS

Results of

set A

Results of

set B

EMPOWER RESULTS

Temperature increase in set A Temperature

increase in set B

Humidity

decreases in

set A Humidity

decreases in

set B

EMPOWER

Discussions 1. Describe the change in temperature in the two

setting of experiment.

2. Describe the change in humidity in the two setting of experiment.

3. From the graph, which setting has higher temperature increase?

4. From the graph, which setting is in high humidity?

5. From the graph, what is the relationship between temperature and humidity?

6. Which setting has higher rate of transpiration?

7. Why did you say so?

Mr Ahmad has a vegetables garden. During the haze hit,

it was found that the vegetables yield in his garden becomes decreased.

From the situation, what happen to the vegetables? Why?

ENHANCE

UNIQUE FEATURES OF THE

ACTIVITY

The temperature sensors are very sensitive. The readings could be taken

accurately until 3 decimal points which could not be done if we are using the

ordinary thermometer in our laboratory.

In conventional method, it is quite impossible for us to measure humidity

accurately, but such procedure could be carried out using data logger easily.

The use of data logger is very efficient and time saving. Data for both setting of

experiment could be collected simultaneously, and the experiment

could be conducted at the same time.

Students can avoid reading error and they can get the accurate data. Data can be

taken although temperature rise is very fast.

UNIQUENESS

UNIQUE FEATURES OF THE

ACTIVITY (continue)

The graph can be plotted easily and save

time.

The use of data logger is no doubt would encourage students’ interest in practical work so as to increase their understanding on a particular topic.

Students are able to see the data easily and on seeing the graph, they are able

to see the relationship between temperature and humidity. .

This will helps a lot to counter students’ misconceptions in temperature and

humidity- when the temperature increase humidity also increases.

UNIQUENESS