Question

What are the four steps of the extravasation process?

A) 1. Vasoconstriction, 2. Platelet activation, 3. Neutrophil recruitment, 4. Macrophage phagocytosis
B) 1. Platelet aggregation, 2. Mast cell activation, 3. Eosinophil recruitment, 4. Lymphocyte proliferation
C) 1. Vasodilation, 2. Monocyte infiltration, 3. B-cell activation, 4. Cytokine release
D) 1. Margination, 2. Diapedesis, 3. Migration, 4. Phagocytosis

Answer 1

The extravasation process involves four steps: margination, diapedesis, migration, and phagocytosis. White blood cells move to the endothelial wall, squeeze through the endothelial cells, migrate toward the infection site, and engulf and destroy pathogens.

Step-by-step explanation:

The four steps of the extravasation process are:

1. Margination: White blood cells move to the endothelial wall of blood vessels.
2. Diapedesis: White blood cells squeeze through the endothelial cells and enter the surrounding tissue.
3. Migration: White blood cells move towards the site of infection or injury.
4. Phagocytosis: White blood cells engulf and destroy pathogens through phagocytosis.

For example, during margination, white blood cells, such as neutrophils and monocytes, attach themselves to the endothelial wall by interacting with adhesion molecules. Then, during diapedesis, these white blood cells squeeze between endothelial cells to enter the tissue.