Cell Wall

Cell Wall

  • In fungi and plants, a non-living and rigid structure known as the cell wall forms an outer covering for the plasma membrane. The cell wall serves multiple crucial functions. 
  • Functions of Cell Wall:

- The cell wall not only provides structural support and shape to the cell but also offers protection from mechanical damage and infections.

- Additionally, it plays a role in cell-to-cell interactions and acts as a barrier to unwanted macromolecules. 

  • Composition in Algae:

- Algae possess cell walls composed of cellulose, galactans, mannans, and minerals such as calcium carbonate.

- These components vary depending on the type of algae. 

  • Composition in Plants:

- In other plants, the cell wall is made up of cellulose, hemicellulose, pectins, and proteins.

-The composition may change as the cell matures. 

  • Primary and Secondary Wall:

- In young plant cells, the primary wall is capable of growth. However, as the cell matures, the secondary wall forms on the inner side, towards the membrane.

- The primary wall growth diminishes over time. 

  • Middle Lamella:

- The middle lamella is a layer primarily composed of calcium pectate.

- It functions to hold or glue adjacent cells together, contributing to the structural integrity of the plant. 

  • Plasmodesmata:

- Cell walls and middle lamellae may contain plasmodesmata, channels that connect the cytoplasm of neighboring cells.

- These channels facilitate communication and the exchange of materials between adjacent plant cells.