Cell Wall & Water

Plant cells

The cell wall is the outer barrier of plants and fungi. This wall is not to be confused with the cell membrane, which virtually all animal and plant cells contain. The cell membrane has both structural and functional attributes. The cell wall is structural, in that it provides an extra layer of protection.

Osmosis

Osmosis is known as the movement of water across a membrane. When water moves into a cell, it could burst. The cell wall stops this from happening because of its rigidity.

Firmness and Shape

Even when a plant takes up a large amount of water for storage, the cell wall helps plant cells to remain firm and keep their shape.

Permeability

The cell wall is permeable to water as well as gases. The wall is capable of holding up to 50 percent of its capacity.

Carrots and Apples

When you bite into vegetables and fruits such as carrots and apples, they crunch--and the cell wall is responsible for that. The cell wall is composed, mainly, of cellulose which is an indigestible material. The cellulose in the cell wall provides the crunch. These plants hold water, so when you bite into them, the water is liberated.

Structure

The cell wall keeps the cell structurally sound. In essence, the cell wall bends but does not break.

References

• "Desiccation and Survival in Plants: Drying Without Dying;" H.W. Pritchard-Black; 2002.