Equal sized potatoes are dipped into water,weak sucrose and strong sucrose solution.Predict
(a)What potato would increase in size
(b)What potato would decrease in size
(c)Comment on the stiffness of the potatoes before and after dipping them into the respective solutions.
(d)What was the aim of the experiment?
To answer these questions, we need to understand the concept of osmosis. Osmosis is the movement of water molecules across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration.
(a) The potato that would increase in size is the one dipped into the weak sucrose solution. This is because the weak sucrose solution has a lower solute concentration compared to the potato cells. As a result, water will move from the area of lower solute concentration (weak solution) into the potato cells through osmosis, causing the cells to swell and the potato to increase in size.
(b) The potato that would decrease in size is the one dipped into the strong sucrose solution. This is because the strong sucrose solution has a higher solute concentration compared to the potato cells. As a result, water will move from the potato cells, where the concentration is higher, to the area of higher solute concentration (strong solution) through osmosis. This loss of water from the cells causes them to shrink, resulting in the potato decreasing in size.
(c) Before dipping the potatoes into the solutions, they are likely to be firm and stiff. After dipping them into the respective solutions, the stiffness of the potatoes will vary. The potato dipped into the weak sucrose solution will become softer and less stiff because the water entering the cells will cause them to swell. On the other hand, the potato dipped into the strong sucrose solution will become even stiffer as water leaves the cells, causing them to shrink and become more dehydrated.
(d) The aim of the experiment is to observe the effect of different concentrations of sucrose solutions on the size and stiffness of potatoes. By dipping identical potatoes into weak and strong sucrose solutions, the experiment aims to demonstrate the process of osmosis and understand how it affects the water movement in and out of plant cells.