The term endotoxin is synonymous with:

• A. A-B toxins.
• B. Lipopolysaccharide (LPS).
• C. Phospholipase.
• D. None of the above.

Answer: (B)

Verified step by step guidance

1. Understand the term 'endotoxin': Endotoxins are toxins that are part of the outer membrane of the cell wall of Gram-negative bacteria.
2. Identify the components of Gram-negative bacteria: The outer membrane of these bacteria contains lipopolysaccharides (LPS), which are large molecules consisting of a lipid and a polysaccharide.
3. Recognize the role of lipopolysaccharides (LPS): LPS is a major component of the outer membrane and is responsible for the toxic effects associated with endotoxins.
4. Differentiate between endotoxins and exotoxins: Exotoxins, such as A-B toxins, are secreted by bacteria and are not part of the cell wall structure, unlike endotoxins.
5. Conclude that the term 'endotoxin' is synonymous with lipopolysaccharide (LPS), as it is the component responsible for the endotoxin activity in Gram-negative bacteria.