Q36.2-4CC. - Campbell Biology

Question

What would happen if you put plant protoplasts in pure water? Explain.

 

Step-by-Step Solution

Answer

If plant protoplast is placed in pure water, water gains entry in the cell without reaching equilibrium stage, resulting in the cell's bursting. The presence of a cell wall can prevent the bursting of cells. 

Step 1: Protoplasm

Protoplasm indicates the plant or bacterial cell with cytoplasm and nucleus in their structure. When the cell wall of the plant cell is removed, consisting of the cytoplasm and nucleus (contain genetic material), the structure is called protoplast. Thus, a cell without a cell wall is called a protoplast. 

Step 2: Role of the cell wall in plant

The cell wall is the structure that provides a protective covering to the plant cell. As it is rigid in nature, it prevents the influx of a large amount of water in the cell. It can also withstand dilute hypotonic media and thus, prevent swelling and bursting of the cell. 

 

Step 3: Effect in protoplast when put in pure water

When a plant protoplast is placed in water, it may burst due to the absence of a cell wall in its structure. Due to the absence of a cell wall, pure water can enter the protoplast (due to hypotonic solution) and result in swelling of the protoplast. 

Cell walls protect cells from harmful materials and limit the protoplast's expansion, thus protecting the cell from bursting. It prevents the swelling and bursting of the cell by limiting the entry of water inside it.