Final answer:
Gram-positive bacteria have a thick layer of peptidoglycan in their cell walls, while plant cell walls are mainly composed of cellulose.
Step-by-step explanation:
In the context of cell wall types, the characteristic you provided is not specified. However, based on the information provided, the cell wall types mentioned are Gram-positive bacteria and plant cell walls. Gram-positive bacteria have a thick layer of peptidoglycan in their cell walls, while plant cell walls are mainly composed of cellulose. It is important to note that the information provided does not directly give a characteristic to place in a specific cell wall type category.