Question

Take four peeled potato halves and scoop each one out to make potato cups. One of these potato cups should be made from a boiled potato. Put each potato cup in a trough containing water.

(a) Keep cup A as empty.
(b) Put one teaspoon sugar in cup B.
(c) Put one teaspoon salt in cup C.
(d) Put one teaspoon sugar in the boiled potato cup D.
Keep these for two hours. Then observe the four potato cups and answer the following.

Explain why water does not gather in the hollowed out portions of A and D.

• A. In A no concentration gradient occurs, in D no semipermeable membrane present
• B. In A no semipermeable membrane, in D no concentration gradient
• C. Both A and B
• D. None of these

Answer 1

The correct option is A In A no concentration gradient occurs, in D no semipermeable membrane present

Cup of potato A is empty and act as a control. Hence, there is no concentration gradient.
Potato D loses its semipermeability due to boiling. Osmosis is a process in which the water molecules move from lower solute concentration to higher solute concentration through a "semipermeable membrane". Thus, the correct answer is option A.