Question

If a cell is isotonic in a 80% sucrose solution, how will the movement of water across the cell membrane affect the size of a cell if it is moved from an 80% sucrose solution to a 40% sucrose solution?

a the cell will reduce in cell will reduce in size.
b the cell will increase in cell will increase in size.
c the cell will remain cell will remain unaffected.
d the cell will increase in size first and then reduce in size.

Answer 1

When moved from an 80% to a 40% sucrose solution, a cell will experience a net inflow of water due to the hypotonic nature of the new environment, causing it to swell and potentially burst. The answer is option B.

Step-by-step explanation:

If a cell is isotonic in an 80% sucrose solution, it means there is no net movement of water across the cell membrane, as the solute concentrations on both sides are equal. Moving the cell from an 80% to a 40% sucrose solution changes this balance. The 40% sucrose solution is hypotonic compared to the cell's interior, leading to a net movement of water into the cell.

According to the principles of osmosis, water will cross from the hypotonic (lower solute concentration) solution to the side with the hypertonic (higher solute concentration), which in this case is the inside of the cell. This influx of water causes animal cells, which lack a rigid cell wall, to swell and may lead to lysis (bursting) of the cell.

Therefore, if the cell is transferred from an 80% sucrose solution to a 40% sucrose solution, the correct answer is (b) the cell will increase in size.