By looking at a plant externally can you tell whether a plant is `C_(3) or C_(4)` ? Why and how?

By looking at which internal structure of a plant can you tell whether a plant is C_(3) or C_(4) ? Explain.

From what you have learnt, can you tell whether enzymes are bigger or DNA is bigger in molecular size ? How did you know ?

Why do you call some plant as fossil plants

Ex situ conservation is used for the conservation of (a) all plants (b) all animals (c) threatened animals and plants (d) both (a) and (b)

Differentiate C_(3) Plants and C_(4) Plants.

A process that makes important difference between C_3 and C_4 plant is: