1. Briefly describe the process of inflammation in an area that has been traumatized.
Answer:
Inflammation is the body's general response to tissue damage, triggered by various factors such as pathogens, abrasions, chemical irritations, or extreme temperatures. Its purpose is to eliminate microbes, toxins, or foreign material at the injury site, prevent their spread, and prepare for tissue repair. The process involves three stages: (1) vasodilation and increased permeability of blood vessels, where arterioles widen and capillaries become more permeable to allow defensive substances into the affected area, (2) emigration of phagocytes (neutrophils and later monocytes transformed into macrophages) from the blood into the tissue to destroy invading microbes through phagocytosis, and (3) tissue repair, which occurs as the inflammatory response subsides. Key substances involved include histamine, kinins, prostaglandins, leukotrienes, and complement. The signs and symptoms of inflammation, remembered by the acronym PRISH (pain, redness, immobility, swelling, and heat), resulting from increased blood flow, permeability, and the body's efforts to heal the damaged area.
2. Choose one type of Immunity (Innate and Humoral) and explain how its mechanism protects our body.
Answer:
Humoral immunity, also known as antibody-mediated immunity, plays a crucial role in protecting the body against extracellular pathogens. This immune response is initiated by B cells that undergo clonal selection upon encountering a foreign antigen. During this process, B cells transform into plasmocytes, which secrete specific proteins called antibodies or immunoglobulins. These antibodies circulate in the blood and lymph, targeting antigens in body fluids. The antibodies produced by a clone of plasmocytes exhibit specificity to a particular antigen, and each B cell clone is capable of secreting only one type of antibody. The antibodies produced by plasmocytes have various functions, including neutralizing antigens, immobilizing bacteria, agglutinating and precipitating antigens, activating complement, and enhancing phagocytosis. Antibodies act by binding specifically to antigens, forming antigen-antibody complexes that facilitate the removal of pathogens by immune cells.
Additionally:
The complement system, a group of proteins activated by antigen-antibody complexes, further enhances the immune response by promoting phagocytosis, cytolysis, and inflammation. Humoral immunity provides immunological memory, resulting in a quicker and more intense secondary response upon reexposure to the same antigen. Memory B cells, formed during the clonal selection process, contribute to this rapid and efficient response by proliferating and differentiating into plasmocytes. Immunological memory is a key aspect of humoral immunity, allowing the body to mount a more effective defense against previously encountered pathogens and forming the basis for vaccination strategies to prevent certain diseases.
References:
Tortora, G., & Derrickson, B. (2012). Principles of ANATOMY & PHYSIOLOGY (13th ed.). John Wiley & Sons, Inc.