Which term best describes a phase marked by increased vascular permeability?

Which term best describes a phase marked by increased vascular permeability?

• A. Permeability changes
• B. Leukocyte migration
• C. Metabolic changes
• D. Ultrastructural changes

Answer: (A)

In acute inflammation, the vascular phase involves the blood vessels becoming more permeable, allowing plasma fluid and proteins to leak into the surrounding tissue and enabling leukocytes to exit the bloodstream. The term that directly names this specific change in the vessels is permeability changes, since it describes the endothelial gaps and leakage that produce edema and protein-rich exudate. Leukocyte migration happens after this permeability increase, while metabolic or ultrastructural changes describe other cellular adjustments but not the primary vascular event.

In acute inflammation, the vascular phase involves the blood vessels becoming more permeable, allowing plasma fluid and proteins to leak into the surrounding tissue and enabling leukocytes to exit the bloodstream. The term that directly names this specific change in the vessels is permeability changes, since it describes the endothelial gaps and leakage that produce edema and protein-rich exudate. Leukocyte migration happens after this permeability increase, while metabolic or ultrastructural changes describe other cellular adjustments but not the primary vascular event.