Briefly describe the process of inflammation in an area that has been traumatized.
1. Vasodilation and Enhanced Blood Vessel Permeability: When cells are damaged, they release inflammatory substances such as histamine, kinins, prostaglandins, leukotrienes, and complements. These substances induce vasodilation and heightened permeability of blood vessels. The dilation increases blood flow to the affected area, resulting in observed redness and heat. Meanwhile, increased permeability allows fluid to exit blood vessels into tissue spaces, causing local swelling (edema). This swelling activates pain receptors as pressure builds in the tissues.
2. Emigration of Phagocytes: Within an hour after the onset of the inflammatory response, phagocytes are mobilized. Neutrophils adhere to the endothelium of blood vessels due to blood accumulation. They then squeeze through the blood vessel wall to reach the damaged site and attempt to phagocytize invading microbes. As neutrophils die in the early stages of inflammation, monocytes follow, transforming into wandering macrophages that engulf damaged tissue, dead neutrophils, and invading microbes.
3. Tissue Repair: Clotting proteins, released into the affected area from the bloodstream, become activated. They create a fibrin barrier to isolate the damaged region, preventing the spread of harmful agents to neighboring tissues. The fibrin mesh also serves as a scaffold for permanent repair. Localized heat enhances the metabolic rate of tissue cells, accelerating their defensive actions and repair processes.
Choose one type of Immunity (Innate and Humoral) and explain how its mechanism protects our body.
Innate (nonspecific) immunity involves mechanical barriers on body surfaces and the cells and chemicals that act as the initial line of defense against invading pathogens. An example of innate defenses is the vaginal secretions, which inhibit bacterial and fungal growth in the female reproductive tract due to its acidic nature.