N3 Anatomy and Physiology AY 2023-2024

The process of inflammation in an area that has been traumatized

• Inflammation is a nonspecific defensive reaction of the body to tissue damage. It is an attempt to dispose of microbes, toxins, or foreign material at the area of injury to prevent further spreading and to prepare for tissue repair. In tissue trauma, inflammation begins when vasodilation occurs at the site for greater blood flow to the area of inflammation. The increased permeability of capillaries allows leakage of blood-clotting factors into tissues. The cell debris and damaged cells induce macrophages to clean them up. Macrophages release cytokines that attract neutrophils, followed by more macrophages, which can phagocytose the dead cells and debris, preparing the site for wound repair.

Innate immunity and its mechanism

• The innate immune system is the body's first line of defense against pathogens or foreign substances entering the body. It reacts to all germs and foreign substances, hence called the "nonspecific" immune system. 

• The innate immune system consists of the first line of defense: skin and mucous membrane, and the second line of defense: immune system cells (defense cells) and proteins. 
  • Pathogens must go through the first line of defense of the body, the skin, and the mucous membrane. The skin acts as a barrier to prevent pathogens from going inside. Wherein the mucous membrane traps foreign pathogens from further entering the body.
  • If in the case that the pathogens pass through the first line of defense, they will go through the second line of defense, immune system cells, and proteins. They will then do specific mechanisms in order to fight off pathogens. 

• It acts very quickly: for instance, it makes sure that bacteria that have entered the skin through a small wound are detected and destroyed on the spot within a few hours. 

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