The role of chlorophyll in photosynthesis

Activity No. ___

The role of chlorophyll in photosynthesis

I. Materials

Beaker Iodine

Test tubes Iron stand

Carbon paper wire gauze

Alcohol lamp iron ring

Leaves test tube rack

Ethanol

II. Procedure

1. Get a sample plant with netter venation.

2. Choose two leaves of similar size from the sample plant.

3. Cover one leaf with carbon paper for one day; leave the other leaf uncovered.

4. Light the alcohol lamp and boil each leaf for 20 seconds to kill the cell.

5. Put out the flame. Then, transfer the leaves in a container or test tube. Add enough ethanol to cover the leaf.

6. Return the test tube to the beaker. Boil until the leaf loses its color.

7. When all the chlorophyll has been extracted, remove the leaves using a forceps. Rinse them with water then dry.

8. After drying, dip the leaves in a glass plate with iodine solution.

9. Observe any color change. A blue-violet color indicates the presence of starch produced and stored by plants.

III. Observation

	Color of the leaf when boiled	Color of the leaf when dipped in iodine
Leaf A
Leaf B

IV. Analysis

1. Why did you boil the leaves in water and alcohol?

2. What is the color of the ethanol? What do you think dissolved on it?

3. Which part of the leaf shows the presence of starch?

4. Can plants produce food without chlorophyll? Explain.

5. Will plants exist without the energy of sunlight? Why or why not?