## Core Concept
The sequence of events in acute inflammation involves a series of coordinated responses to tissue injury or infection. This process includes vascular changes, cellular responses, and the release of chemical mediators. Understanding the sequence is crucial for managing inflammatory conditions.
## Why the Correct Answer is Right
The correct sequence of events in acute inflammation is:
1. **Vasodilation** - Increased blood flow to the affected area.
2. **Increased vascular permeability** - Leaking of fluid and proteins into the interstitial space, causing edema.
3. **Exudation of fluid and cells** - Movement of leukocytes, primarily neutrophils, into the affected area.
4. **Phagocytosis** - Engulfment and destruction of pathogens by neutrophils and macrophages.
## Why Each Wrong Option is Incorrect
**Option A:** A sequence that starts with increased vascular permeability is incorrect because vasodilation precedes increased permeability.
**Option B:** A sequence that places exudation of fluid and cells before vasodilation is incorrect because vasodilation must occur first to increase blood flow.
**Option D:** A sequence that ends with vasodilation is incorrect because vasodilation is an early event, not the final step.
## Clinical Pearl / High-Yield Fact
A key point to remember is the **4 cardinal signs of inflammation**: redness (rubor), heat (calor), swelling (tumor), and pain (dolor), which are primarily due to vasodilation and increased vascular permeability.