Photosynthetic Clues

Photosynthetic Clues

Materials:

Mature leaves of variegated mayana plant, alcohol burner, evaporating dish, iron stand, 250ml beaker, dropper, iron ring, iron stand, wire gauze, dissecting set, petri dish,  iodine solution, ethyl alcohol.

Procedure:

1. Examine the leaf of variegated mayana . Sketch the leaf and note the probable distribution of the chlorophyll (green areas).

2. Place the leaf in boiling water for a few minutes.

3. Take out of the boiling water with a pair of tweezers then immerse the leaf in the evaporating dish containing ethyl alcohol.

4. Place the evaporating dish in a warm water bath until the leaf is totally bleached.

5. Rinse the leaf with water and place it in the petri dish. Put three drops of dilute of iodine solution.

Questions:

1. What is the purpose of immersing the leaf in ethyl alcohol?

2. Compare the pigmented mayana leaf with the bleached leaf.

3. Is starch present in the leaf? What does the presence of starch indicate? Why?

4. What can u infer from the activity?