Activity 1
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Briefly describe the process of inflammation in an area that has been traumatized.
During an inflammation, certain substances, such as histamine released by MAST cells, and other substances cause the blood vessels to dilate (vasodilation), which allows more blood to flow through the damaged area. At the same time, these substances increase the permeability of defensive proteins (e.g., antibodies and clotting factors) to enter the injured site. Moreover, after vasodilation and increased permeability of defensive proteins, the individual begins to exhibit signs and symptoms such as heat, redness, swelling, and pain.
After this, the emigration of phagocytes occurs, wherein the neutrophils infiltrate the site of injury and destroy the invading microbes by phagocytosis. However, since neutrophils rapidly die off, they are followed by monocytes, which later on differentiate into wandering macrophages that will clear off the pathogens, injured cells, and dying neutrophils. Once done, the macrophages are cleared from the tissue by the lymphatic capillaries. These then prompt the immune cells to start producing anti-inflammatory mediators instead of pro-inflammatory mediators, which will now terminate the inflammation and precede the repair of damaged tissue.
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Choose one type of immunity (Innate and Humoral) and explain how its mechanism protects our body.
Since innate immunity is the kind of immunity that is present at birth, it serves as the body's first line of defense against pathogens and infection during the crucial initial hours and days of exposure to a new pathogen. Given that the immune responses are non-specific and include general pattern recognition, this type of immunity reacts more swiftly than adaptive immunity. The first line of defense and the second line of defense are the two mechanisms of the innate immune system. The skin and mucous membranes are the first line of defense because they offer both chemical and physical barriers that inhibit pathogens and foreign objects from entering the body and causing disease. In regard to this, the mucous membranes capture microbes and foreign objects and subsequently expel these pathogens from the body in various ways (e.g., sneezing, coughing, vomiting, secretions, etc. ), while the skin sheds on a regular basis to remove microbes from the skin's surface. However, the second line of defense supplants this activity and prevents further infection through the aid of antimicrobial substances (such as interferons), phagocytes, NK cells, inflammation, and fever when the first line of defense is insufficient and is further penetrated by the pathogens.