Answer the following questions:
1. Briefly describe the process of inflammation in an area that has been traumatized.
The cell debris and damaged cells in an area that has been traumatized, but not infected induce macrophages to clean them up. Macrophages attract neutrophils and more macrophages by releasing cytokines. Chemical mediators that are released contribute to vasodilation and increased blood vessel permeability, allowing more blood to flow, hence, defensive proteins and clotting factors can enter the site of the damaged area. Phagocytes then move, destroy, and engulf dead cells and debris, preparing the site for tissue repair.
2. Choose one type of Immunity (Innate and Humoral) and explain how its mechanism protects our body.
Innate immunity includes body defenses that are present at birth and genetically determined. These physical and chemical barriers prevent, remove, and destroy microorganisms. Barriers to innate immunity include the skin and mucous membranes and internal defenses.
The skin and mucous membranes of the body are our first line of defense against disease-causing agents. The outer epithelial layer of our skin (epidermis) provides a barrier that keeps bacteria and germs from entering the body and bloodstream. Moreover, the periodic shredding of the epidermal cells removes the microbes at the skin's surface. On the other hand, the mucous membrane, the inner epithelial layer, secretes mucus, which moistens and lubricates the body cavity. Mucus traps many microbes and foreign substances due to its viscosity.
When disease-causing agents were able to penetrate our first line of defense, they encounter the second line of defense which are the internal antimicrobial substances, phagocytes, natural killer cells, inflammation, and fever. Antimicrobial substances discourage microbial growth through the production of proteins called interferons that stop the replication of viruses, activation of normally inactive proteins (complement) that enhance specific immune reactions, reduction of the amount of available iron—through iron-binding proteins—that inhibits the growth of certain bacteria, and production of antimicrobial proteins that have a broad spectrum of antimicrobial activity. Natural killer cells and phagocytes (neutrophils and macrophages) can kill various infected cells and specific tumor cells and ingest microbes and cell debris, respectively. Inflammation is a defensive response of our body against tissue damage. Fever, induced by pyrogens, occurs during infection and inflammation. It intensifies the effects of interferons, speeds up body reactions that aid repair, and inhibits the growth of some microorganisms.
Reference
G. J. & Derrickson, B. (2014). Principles of Anatomy and Physiology. 14th ed. New York: John Wiley & Sons, Inc.
Regan, J., Russo, A., Seeley, R., Stephens, T., Tate, P., & VanPutte, C. (2019). Seeley's Anatomy and Physiology. 12th ed. New York, NY: McGraw-Hill Education.