The cell walls of fungi are primarily composed of d) chitin. Chitin is a long-chain polymer of N-acetylglucosamine, which is a derivative of glucose. It is a structural component in the cell walls of fungi, providing both rigidity and protection.
Cell walls in fungi serve various essential functions, including maintaining the shape of the fungus, protecting against mechanical damage, and acting as a barrier to pathogens. Unlike plants, which have cell walls made of cellulose, fungi have evolved to use chitin due to its unique properties, which help them thrive in various environments.