Question

A cell containing only pure water is placed into a solution containing 1M sucrose. The cell's membrane is impermeable to water, sucrose, sodium ions and chloride ions. How could you make the cell isosmotic to the outside solution? Choose all of the correct answers. a. Add NaCl to the inside of the cell until it contains 1M NaCl. b. Add NaCl to the inside of the cell until it contains 0.5M NaCl. c. Increase the number of sodium channels on the cell membrane. d. Increase the active transport of water out of the cell. e. Add sucrose to the cell until it contains 1M sucrose.

Answer 1

Answer: b and e

Explanation:

Two solutions are isotonic to each other if the have the same osmotic pressure.

Since the cell is impermeable to sucrose, sodium and chloride ion outside the cell, For the solution inside the cell to be isoosmotic to the solution outside the cell, same 1M of sucrose should be added to the solution inside the cell to balance osmotic pressure.

If osmolarity is the concentration of a solution expressed as the total number of moles per litre, also the addition of an ionic 0.5M Na+Cl- to the solution inside the cell will also balance the osmotic pressure.

0.5M if NaCl will dissociate and create an equivalent 1M osmotic pressure inside the cell.