Distinguish between the following pairs on the basis of words indicated in the brackets:

Diffusion and active transport (concentration gradient)

Distinguish between the following pairs on the basis of words indicated in the brackets:

Nitrogen and Potassium (role in plants)

An experiment was set up as shown in the figure below. After some time, the water level in test tube A fell down but not in test tube B.

Why was there a fall in the water level of test tube A and not in that of test-tube B?

Given alongside is an experimental set up. Study the figure and answer the following questions:

(a) What is the main objective of the experiment?

(b) Name the tissue which is responsible for the process shown in the figure.

(c) Name two dyes which can be used in the above experiment to make a coloured solution.