What is the function of:
$(a)$ Cellulose in the cell wall?
$(b)$ The presence of deeply folded membranes in mitochondria?
$(c)$ Digestive enzymes in lysosomes?

(N/A) Cellulose provides structural strength and helps in maintaining the shape and integrity of the cell.
$(b)$ The deeply folded membranes,known as cristae,increase the surface area for $ATP$ generating chemical reactions,thereby enhancing the efficiency of cellular respiration.
$(c)$ Digestive enzymes in lysosomes help in breaking down complex organic food into simple nutrients,digesting foreign particles like bacteria or viruses,and removing old or worn-out cell organelles through autophagy.