Question

Following observations are made for a plant grown under different cinditions.
I. Chloride and magnesium in soil + light $\to$ green plant
II. I. Chloride and magnesium in soil + dark $\to$ etiolated plant
III. Magnesium + light $\to$ green plant
IV. Intermittent light flashes + chloride $\to$ etiolated plant
From the above observations, it is concluded that the factors necessary for the green colour in plants are

• A. chloride and light
• B. chloride, magnesium and light.
• C. magnesium and light.
• D. flash of light with chloride

Answer 1

The correct option is C magnesium and light.

Without sufficient amounts of magnesium, plants begin to degrade the chlorophyll in the old leaves. This causes the main symptom of magnesium deficiency or yellowing between leaf veins, giving the leaves a marbled appearance.

So, the correct option is 'magnesium and light.'.