Teaching concepts

Examples and non-examples

E.g.:The example of solution is salt water and non-example of mixture is pepper and water.

Besides, the following techniques will be useful for teachers in teaching such as the misconception on Calvin cycle (dark cycle) can only operate in the darkness).

Concpet map

For light reaction and Calvin cycle, indeed both of them had involved many steps and students might lost their mind in examine the relationship between light reaction and Calvin cycle. Using an advance organizer will be effective in teaching; it had been indicated energy from sunlight is used to produce ATP and NADPH while Calvin cycle is using both of them to produce high-energy sugars. Hence, Calvin cycle is light dependent.








Image and analogies

Using the images in teaching the will be useful in introducing the topic photosynthesis.
It shows clearly that the intimate interrelated ship between light reaction and Calvin cycle.








Computer simulation

To review the role of NADPH and ATP in the Calvin cycle that serves to produce starch, using a computer simulation is more effective to describe rather than memorizing a series of equations involved. The goal is to help students to build a relationship on the importance of light reactions in Calvin cycle.

Experiment

In addition, an experiment on the need for light in photosynthesis can be carried out among students.

The plant was kept in the dark for 48 hours. The plant (with leaves covered as shown) was then exposed to sunlight for 6 hours. The covered leaves were then tested with iodine.

It is observed that no blue-black color was observed in the leaf covered with card board stencil. A blue-black color was observed in the control leaf without covered with card board stencil.

light reaction does not convert carbon dioxide into a carbohydrate which is an integral part of photosynthesis.

That means, starch is produced in Calvin cycle. Based on the observation of experiment indicated that starch is not exist in the leaf covered with light-proof paper (iodine, brown color will turn to dark blue in the presence of starch), It is then can be concluded Calvin cycle only produce starch in the presence of light.