The cork cells become impervious to water, gases and nutrients due to the deposition of suberin.

Cork cells and their imperviousness to water and gas

Cork cells possess unique characteristics that make them highly impervious to water and gas. This imperviousness is primarily attributed to the presence of two substances: lignin and suberin. These compounds play a crucial role in the structure and function of cork cells, providing them with exceptional properties that make cork a valuable material in various industries.

Lignin:

Lignin is a complex polymer found in the secondary cell walls of many plants, including cork. It is a hydrophobic substance, meaning it repels water. The presence of lignin in cork cells contributes significantly to their impermeability to water and gas. Here's how:

1. Hydrophobic nature: Lignin is a hydrophobic compound, meaning it prevents the penetration or absorption of water. It forms a barrier that restricts the movement of water molecules through the cell walls of cork cells.

2. Secondary cell wall reinforcement: Lignin provides structural support to the secondary cell walls of cork cells. It fills the spaces between cellulose fibers, making them more rigid and less permeable to water and gas. This reinforcement strengthens the cell walls, reducing their porosity and preventing the passage of substances.

Suberin:

Suberin is a waxy substance found in the cell walls of cork cells. It is a highly hydrophobic and lipophilic material, meaning it repels both water and gases. Suberin plays a crucial role in enhancing the impermeability of cork cells in the following ways:

1. Water repellency: Suberin creates a waterproof barrier, preventing water from entering or leaving the cork cells. It forms a protective layer that acts as a shield against moisture, reducing the chances of water absorption and consequent damage to the cells.

2. Gas impermeability: Suberin also inhibits the movement of gases through cork cells. It prevents the escape of gases from the cells, making cork an effective material for sealing purposes. This property is highly beneficial in applications where airtightness is required, such as wine bottle stoppers or the insulation of buildings.

Overall, the presence of lignin and suberin in cork cells contributes to their exceptional impermeability to water and gas. These compounds form hydrophobic barriers, reinforcing the cell walls and creating a waterproof and airtight environment. This unique characteristic of cork cells makes cork a valuable material in various industries, including construction, packaging, and insulation.