Question

Help Please:
A normal plant cell holds water in the vacuole of the cell. This large organelle also gives the cell support. Suppose a plant is submerged in salt water. As a result, the vacuoles collapse and the leaves wilt. This condition is called plasmolysis. Which explanation do you think best describes what happens to the cells of that plant during plasmolysis?

Answer 1

Plasmolysis is the contraction of a cell due to the loss of water through osmosis in plants and bacteria. Osmosis is the net diffusion of water across a selectively permeable membrane, such as a cell membrane, from an area with a high water potential to an area with a low water potential.

If a plant cell is placed in a more concentrated salt (hypertonic) solution, the plant cell loses water and hence turgor pressure, making the plant cell flaccid. Plants with cells in this condition wilt. Further water loss causes plasmolysis: pressure decreases to the point where the protoplasm of the cell peels away from the cell wall, leaving gaps between the cell wall and the membrane. Eventually cytorrhysis – the complete collapse of the cell wall – can occur. There is no mechanism in plants to prevent excess water loss in the same way as excess water gain, but plasmolysis can be reversed if the cell is placed in a weaker solution (hypotonic solution). The equivalent process in animal cells is called crenation. The liquid content of the cell leaks out due to diffusion. The cell collapse and cell membrane pulls away from the cell wall(in plants). Most all animal cells consist of only a phospholipid bilayer and just shrink up.

Plasmolysis only occurs in extreme conditions and rarely happens in nature. It is induced in the laboratory by immersing cells in strong saline or sugar solutions to cause exosmosis, often using Elodea plants or onion epidermal cells, which have coloured cell sap so that the process is clearly visible.

Plasmolysis can be of two types. It can be either concave plasmolysis or convex plasmolysis. Convex plasmolysis is always irreversible while concave plasmolysis is usually reversible.

Answer 2

The vacoules will not collapse so easly, I think here happening a reversible plasmolysis. ( up on replacing the plant in a normal water medium this will come to normal plant )

Answer 3

A normal plant cell holds water in the vacuole of the cell. This large organelle also gives the cell support. Suppose a plant is submerged in salt water. As a result, the vacuoles collapse and the leaves wilt. This condition is called plasmolysis. Which explanation do you think best describes what happens to the cells of that plant during plasmolysis?