Question

When a freshly collected Spirogyra filament is kept in a 10% potassium nitrate solution, it is observed that the protoplasm shrinks in size:

a. What is this phenomenon called?

When a freshly collected Spirogyra filament is kept in a 10% potassium nitrate solution, it is observed that the protoplasm shrinks in size:

b. What will happen if the filament is replaced in distilled water?

Answer 1

A) Hypertonic

10% potassium nitrate solution represents a hypertonic solution that has a lower water potential as compared to the cytoplasm of the cell.

Plasmolysis

When a cell is placed in a hypertonic solution, the water moves out of the cell due to the difference in the water potential (from higher water potential to lower water potential) and causes the protoplasm to withdraw from the cell wall shrinking of protoplasm). This process is called plasmolysis.


Final answer

Plasmolysis

B) Hypotonic

Distilled water is a hypotonic solution and has a higher water potential as compared to the cytoplasm of the cell.

Deplasmolysis

When a cell is placed in hypotonic solutions, the water moves into the cell due to the difference in water potential and causes the cell to swell, this process is called deplasmolysis.

Final answer

Deplasmolysis