Question

1. Why do we selected variegated leaves in the experiment to show that chlorophyll is necessary for photsynthesis? 2.Why does the guard cells become flaccid? 3.What is the deficiencywhich turns the leaf yellow?

Answer 1

1. variegated leaf is selected because such leaf has patches of chlorophyll. Some part of leaf is with chlorophyll (green) and some is without chlorophyll (nongreen).
2. Garud cells loose water because of low concentration in the cytoplasm and loose their turgidity.
3. Magnesium deficiency causes yellow coloration of leaf.

Answer 2

1) Variegated leaves have some portion of green color while other of white color or colorless. Colored area represents the presence of chlorophyll white colorless portion shows the absence of the green pigment.

2) When plant is not watered properly and is deficient of water, the walls of guard cells contract and shows the flaccid guard cells.

3) The main component of chlorophyll is magnesium.  Yellow color represents the deficiency of element magnesium.

Explanation:

Chlorophyll is the green pigment present in the plant and performs two functions:-

• Gives green colour to plant.
• Help in capturing solar energy and converting it into chemical energy that is used to carry out the process of food synthesis