1. Inflammation exhibits the signs and symptoms of redness, pain, heat, and swelling. It is part of the non-specific immunity of the body. It occurs in three stages. The first stage is vasodilation and increased blood vessel permeability. Vasodilation increases the blood flow in the inflamed area; consequently, the increased permeability allows faster travel of defensive proteins, clotting factors, and antibodies.
The second stage is the emigration of phagocytes. In the emigration of phagocytes, neutrophils and monocytes migrate toward the sites of inflammation. The last stage is tissue repair where the affected areas recover from the inflammation.
2. Choose one type of Immunity (Innate and Humoral) and explain how its mechanism protects our body.
Innate immunity involves the first and second line of defense. The first line includes the skin and mucous membranes. The physical barriers provided by the skin and mucous membranes defend against microbes. The mucus produced traps pathogens that enter the body’s airways. Structures like cilia and hair protect the upper respiratory tract. The chemical barriers present in sebum, sweat, and gastric juices provide the additional first line of defense for ingested microbes.
The second line of defense includes the following antimicrobial substances: interferons (IFNs), normally inactive proteins, iron-binding proteins, and antimicrobial proteins (AMPs). IFNs are released by viruses. Detection of IFNs induces the production of antiviral proteins that stop virus replication within cells. Typically inactive proteins are part of the complement system that amplifies some immune reactions. Iron-binding proteins like transferrin and hemoglobin reduce the available iron which impedes the growth of bacteria in the body. AMPs are short peptides that perform a wide range of antimicrobial activities. An interesting fact is that microbes that were exposed to AMPs do not develop antimicrobial resistance.