Which of the following statements about the cell walls of Archaea is correct?

• A. Archaeal cell walls are identical to those of Bacteria and contain peptidoglycan.
• B. Archaeal cell walls are composed primarily of chitin.
• C. All Archaea have cell walls made of cellulose.
• D. Archaeal cell walls lack peptidoglycan.

Answer: (D)

Verified step by step guidance

1. Understand the composition of bacterial cell walls: Bacterial cell walls typically contain peptidoglycan, a polymer consisting of sugars and amino acids that provides structural support.
2. Recognize that archaeal cell walls differ fundamentally from bacterial cell walls: Archaea do not have peptidoglycan; instead, they have unique cell wall components such as pseudopeptidoglycan, proteins, or polysaccharides.
3. Recall that chitin is a structural polysaccharide found mainly in fungal cell walls and some exoskeletons, not in archaeal cell walls.
4. Note that cellulose is a polysaccharide found in plant cell walls, not in Archaea.
5. Conclude that the correct statement is that archaeal cell walls lack peptidoglycan, distinguishing them from bacterial cell walls.