Immunology is a branch of the biology involved with the study of the immune system, components of the immune system, its biological process, the physiological functioning of the immune system, types, its disorder and lot more. The immune system acts as a body’s defence system by protecting our body cells, tissues and organs from invading infection through various lines of defence.
The immune system functions as a physical barrier and avoid the entry of pathogens including the harmful microorganisms and other disease-causing microbes. Under certain conditions, when our immune system stops functioning, then this results in infectious diseases, such as allergies, Fever, Flu, and may also lead to a dreadful disease like cancer and etc.
The term was coined by Russian biologist Ilya Ilyich Mechnikov, Who advanced studies on immunology and received the Nobel Prize for his work in 1908. He pinned small thorns into starfish larvae and noticed unusual cells surrounding the thorns. This was the active response of the body trying to maintain its integrity. It was Mechnikov who first observed the phenomenon of phagocytosis, in which the body defends itself against a foreign body.
Immune System consists of different types of cells and molecules which protect our body against pathogens. Pathogens are defined as everything from parasites to fungi, bacteria, viruses, and haptens. Haptens are molecules that may cause an immune response when comes in contact with a protein. All these cells and molecules are distributed in all the tissues of the body as well as lymphoid organs which eliminate or prevent microbial infectious diseases to decrease the growth of tumours and starts the repairing process of damaged tissues.