What is the main function of plant cell walls?

The main function of plant cell walls is indeed to provide structural support and protection, but they also play a crucial role in allowing the intake of water and gases. The cell wall is primarily composed of cellulose and other polysaccharides, which create a rigid framework that maintains the shape of the plant cell while being permeable to water and small molecules.

The ability of the cell wall to permit the passage of water is vital for maintaining turgor pressure, which is essential for plant health and growth. Moreover, the presence of pores called plasmodesmata in the cell wall facilitates communication and transport between adjacent cells, allowing for the exchange of gases like carbon dioxide and oxygen necessary for photosynthesis and respiration.

While storing genetic information is a function of the nucleus, controlling nutrient uptake pertains more to the cell membrane's role rather than the cell wall. Although the cell wall provides support, it does not directly assist in the process of photosynthesis, which primarily occurs in the chloroplasts. Therefore, the main role of the plant cell wall in relation to intake of water and gases is what highlights its critical function in plant physiology.