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Briefly describe the process of inflammation in an area that has been traumatized.
Inflammation is the body's general, defensive response to remove bacteria, toxins, and other foreign substances from the site of injury and prevent them from spreading to other tissues. Inflammation also prepares the site for tissue repair, allowing tissue homeostasis to be reestablished. Pathogens, abrasions, chemical irritations, cell disruption, and high temperatures can all cause this type of response. Pain, redness (erythema caused by increased blood flow to the site of damage), immobility, swelling (edema caused by increased blood vessel permeability), and heat are all signs and symptoms of inflammation.
The inflammatory response includes three fundamental stages. The first is vasodilation and increased blood vessel permeability. Vasodilation, or an increase in arteriole diameter, permits more blood to flow past the site of injury, aiding in the elimination of microbial toxins and dead cells. Enhanced capillary permeability allows defense proteins such as antibodies and clotting factors to move from the blood to the tissues. The increased permeability permits clotting to begin at the site of injury, where fibrinogens form a mesh of insoluble and thick fibrins that localize and trap microbes. Histamine, kinins (which may also be the cause of pain associated with inflammation), prostaglandins (which stimulate phagocyte emigration and may intensify and prolong inflammation-associated pain), and leukotrienes (which function in phagocyte adherence to pathogens and may attract phagocytes) are all substances that contribute to vasodilation and increased permeability. Furthermore, the complement system, a system of plasma proteins, contributes to the stimulation of histamine release, the attraction of neutrophils via chemotaxis, the facilitation of phagocytosis, and the elimination of bacteria.
The transport of phagocytes from the circulation into the interstitial fluid is the second step of the inflammatory reaction. This phase is reliant on chemotaxis, which is a guided movement that permits cells like neutrophils (the first to react) to reach regions of inflammation or infection. As the first players, neutrophils play a significant role in adhering to the lining of blood vessels, where they attempt to eliminate invading bacteria via phagocytosis. When neutrophils die, they are replaced by monocytes, which become attached to tissues and change into macrophages capable of engulfing dead cells and invading microorganisms. Within some time, dead phagocytes and injured tissue accumulate and occasionally reach the body's surface; this is known as pus (Tortora and Derrickson, 2017). The appearance of pus may indicate whether the wound is healing (clear or pinkish) or infected (yellowish with some odor). Finally, the tissue repair or regeneration phase takes place. This phase is required to keep the body's equilibrium. Cell division, differentiation, and specification, as well as angiogenesis and extracellular matrix regeneration, are all involved in tissue repair.
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Choose one type of Immunity (Innate and Humoral) and explain how its mechanism protects our body.
Immune defenses that are present at birth are referred to as innate (nonspecific) immunity. This type of immunity acts rapidly but doesn't require specific recognition of bacteria and functions uniformly against all microorganisms. Innate immunity is comprised of the skin and mucus membranes (the first line of protection) as well as antimicrobial chemicals, natural killer cells, phagocytes, inflammation, and fever (the second line of protection). Innate immune responses serve as immunity's early warning system, preventing microorganisms from invading the body and assisting in the elimination of those that do (Tortora and Derrickson, 2017). One illustration of innate immunity is the presence of vernix caseosa which is a film-like covering of the fetus’s skin that protects the newborn from microorganisms and microbial floras.
Reference:
Tortora, G. J., & Derrickson, B. (2017). PRINCIPLES OF ANATOMY & PHYSIOLOGY (15th ed.).