Question

The diagram below represents an experiment conducted to prove the importance of a factor in Photosynthesis.

Study the same and then answer the questions that follow :

(i) Name the factor being studied in this experiment ?

(ii) Why was the plant kept in a dark room before conducting the experiment?

(iii) Why was the experimental leaf then kept in

1. boiling water; 

2. methylated, spirit ?

(iv) Name the solution used to test for presence of starch in the leaf.

(v) What will we observe in the experimental leaf at the end of the starch test ?

(vi) Give a balanced chemical equation to represent the process of photosynthesis.

Answer 1

(i) To show that light is necessary for photosynthesis.

(ii) To destarch, it i.e., to remove all starch from its leaves.

(iii) 

1. To kill the cells.

2. To destroy chlorophyll from the cells.

(iv) Iodine.

(v) The exposed parts of leaf give a positive test for starch and turn blue-black and the part covered with black paper will remain brown, showing the absence of starch.