Which of the following may be produced by pathogenic bacteria?

• A. Antibodies
• B. Chlorophyll
• C. Cellulose
• D. Exotoxins

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the question is asking about substances produced by pathogenic bacteria. Pathogenic bacteria are those that cause disease in a host.
2. Step 2: Review each option to determine if it is typically produced by bacteria, especially pathogenic ones. Antibodies are produced by the immune system of animals, not bacteria.
3. Step 3: Chlorophyll is a pigment involved in photosynthesis, found in plants and some bacteria, but not typically in pathogenic bacteria.
4. Step 4: Cellulose is a structural polysaccharide found in plant cell walls and some bacteria, but it is not commonly associated with pathogenic bacteria or their virulence factors.
5. Step 5: Exotoxins are toxic proteins secreted by certain pathogenic bacteria that contribute to disease symptoms. Therefore, exotoxins are substances produced by pathogenic bacteria.