Question

Plasmolysis in a plant cell is defined as
A) Break down (lysis) of plasma membrane in hypotonic medium
B) Shrinkage of cytoplasm in hypertonic medium
C) Shrinkage of nucleoplasm
D) None of the above

Answer 1

Hint: Plasmolysis is a reversible process and addition of hypotonic solution can lead the expansion of protoplast and reinstatement of original turgor pressure. Plasmolysis is one of the results of osmosis. It happens in extreme conditions like when the cell is placed in a hypertonic solution. An example of plasmolysis is higher concentration of salt and sugar is used in pickles and jam. Due to the higher concentration, the microbes get plasmolysed.

Complete answer:
Let’s first understand the plant mechanism.
> Plasmolysis is the process by which a plant cell loses water when placed in a hypertonic solution. The actual process behind this is the movement of water outwards due to osmosis.
> Plasmolysis is defined as the process of shrinkage of the cytoplasm as a result of loss of water from the cell. It happens when plant cells are engaged in a solution that has a higher deliberation of solutes than the cell does. This plant cell is saved in a hypertonic solution.
> Plasmolysis takes place in the extreme loss of water from the cell, and this makes it a rare occurrence naturally. It can be observed when the plants are uncovered to sea flooding or chemical weedicides.
> During the plasmolysis majority of osmotic water flows into the central vacuole and drastic changes in the protoplast size and shape can affect the subcellular architecture of the plant cell.

So, the correct answer is option (B) Shrinkage of cytoplasm in hypertonic medium.

Note: Plasmolysis plays a vital role in food preservation and storage. We add salt to preserve the jam, meat, jellies or pickle etc. that increase the osmotic pressure of the food. The cells after plasmolysis shrink, whereas if the cells swell on deplasmolysis. For plasmolysis to take place, a hypertonic medium is necessary.