Question

Study the diagram given below and fill in the blanks with suitable words:

In order to prove that carbon dioxide is necessary for

(a) ______, a potted plant is placed in dark for 48 hours to (b) ______ the leaves. A part of a leaf is inserted into a conical flask containing potassium hydroxide solution. This is to absorb (c) ______ from the flask. The plant is then placed in sunlight for a few hours. The experimental leaf is tested for starch. The part of the leaf that was inside the conical flask turns (d) ______, whereas the part of the left outside turns (e) ______ in colour.

Answer 1

(a) Photosynthesis, a potted plant is placed in dark for 48 hours to (b) destarch the leaves. A part of a leaf is inserted into a conical flask containing potassium hydroxide solution. This is to absorb (c) carbon dioxide from the flask. The plant is then placed in sunlight for a few hours. The experimental leaf is tested for starch. The part of the leaf that was inside the conical flask turns (d) colourless, whereas the part of the left outside turns (e) blue-black in colour.