Nokea
For enteropathogenic E. coli is true:
- A. They attach to enterocytes and destroy microvillus
- B. They are invasive and produce enterotoxin (no enterotoxin)
- C. Cause disease clinically similar to bacterial
- D. None of the above
Correct Answer: A
Rationale: Correct Answer: A
Rationale:
1. Enteropathogenic E. coli (EPEC) attach to enterocytes via a type III secretion system.
2. Once attached, they form attaching and effacing lesions on the microvilli, leading to microvillus destruction.
3. This mechanism allows EPEC to cause diarrhea by disrupting the normal absorptive function of the intestines.
Summary:
- B (They are invasive and produce enterotoxin) is incorrect because EPEC are non-invasive and do not produce enterotoxins.
- C (Cause disease clinically similar to bacterial) is vague and does not provide specific information about EPEC pathogenesis.
- D (None of the above) is incorrect as A is the correct explanation for EPEC pathogenicity.
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