Immune systems

Immune System

The Immune System (/ɪˈmjuːn ˈsɪstəm/) is a complex network of cells, tissues, and organs that work together to defend the body against harmful invaders such as bacteria, viruses, and disease-causing microorganisms, or pathogens.

Etymology

The term "immune" comes from the Latin word "immunis," which means "exempt," referring to the body's ability to protect itself from harmful substances. The term "system" comes from the Greek word "systēma," which means "a whole compounded of several parts."

Function

The primary function of the Immune System is to identify and eliminate pathogens. It does this through a series of steps known as the immune response. This involves the production of White Blood Cells, the production and release of Antibodies, and the activation of other protective molecules and processes.

Components

The Immune System is composed of various components, including:

White Blood Cells: These cells are the key players in the immune response. They are produced in the bone marrow and circulate in the blood and lymphatic system.
Antibodies: These are proteins produced by the immune system in response to an infection. They bind to specific antigens on the surface of pathogens, marking them for destruction.
Lymphatic System: This system is a network of vessels and nodes that carry a clear fluid called lymph. It plays a crucial role in the immune response by transporting white blood cells and antibodies to areas of infection.
Spleen: This organ filters the blood and helps the body fight infections.
Thymus: This gland produces T-cells, a type of white blood cell that plays a crucial role in the immune response.

Related Terms

Inflammation: This is a protective response of the immune system to injury or infection.
Autoimmune Disease: This is a condition in which the immune system mistakenly attacks the body's own cells.
Immunodeficiency: This is a state in which the immune system's ability to fight infectious disease is compromised or entirely absent.