Which of the following components is found in the cell wall of Gram-positive bacteria but not in Gram-negative bacteria?

• A. Teichoic acids
• B. Lipopolysaccharide
• C. Periplasmic space
• D. Outer membrane

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the structural differences between Gram-positive and Gram-negative bacteria, focusing on their cell wall composition.
2. Step 2: Recall that Gram-positive bacteria have a thick peptidoglycan layer, which contains unique components such as teichoic acids embedded within it.
3. Step 3: Recognize that Gram-negative bacteria have a thinner peptidoglycan layer but possess an outer membrane containing lipopolysaccharides (LPS), which are absent in Gram-positive bacteria.
4. Step 4: Note that the periplasmic space is a feature found in Gram-negative bacteria between the outer membrane and the plasma membrane, but it is not prominent in Gram-positive bacteria.
5. Step 5: Conclude that teichoic acids are specific to the cell wall of Gram-positive bacteria and are not found in Gram-negative bacteria, distinguishing them from the other listed components.