The Cell Wall
One of the most unique factors about a plant cell is the presence of the cell wall. The cell wall is significantly thicker( the thickness and composition of the cell wall varies with the age, tissue and species of plant) and more rigid than the plasma membrane and was even observed by Robert Hooke when he first observed a plant cell using a simple microscope. The cell wall in a plant cell wall is comprised of mainly cellulose Micro fibrils and its main functions of a cell wall is for strength, protecting the cells insides; as well as for maintain the cells shape and preventing it from bursting.
Usuallly a Cell wall also has its own structure with many plant cells having both a primary cell wall that houses the cell as it grows, and a secondary cell wall. The secondary
wall develops inside the primary wall after the cell has stopped growing. However this not same for all plant cells as there are some that will not have a secondary cell wall in which case the primary cell wall will remain unchanged throughout the growth process. The primary wall is also generally thinner than the secondary wall.
The cell wall can be found in other kingdoms such as fungi, some protists and bacteria.
Fungi Cell Wall- Comprised of chitin
Bacteria Cell Wall- Comprised of peptidoglycan (polymers made of sugars and polypeptides) (Sepala. (UNKNOWN). Organelles. In: Sepala Synaptic Training. Australia:
The Foundations and Walls
An airport needs to be built on a thick rigid foundation in order for it to remain standing and prevent it from collapse. The foundations must also be strong in order to maintain it shape in the unlikely situation of an earthquake. The walls of the Airport can be considered the secondary cell wall, not really needed but as the airport grows ( is being built over time) the walls are added for extra protection.