Immune system

Definition

The immune system is a complex network of cells, tissues, and organs that work together to defend the body against pathogens, including viruses, bacteria, and foreign bodies. It identifies and neutralizes potentially harmful substances while remembering past invaders for faster response in future encounters.

Related terms

Antibodies: Proteins produced by B-cells that specifically target and neutralize foreign substances such as viruses and bacteria.

Lymphocytes: A type of white blood cell that plays a central role in the immune response; includes both B-cells and T-cells which have specific functions in fighting infections.

Antigen: Any substance that triggers an immune response by being recognized as foreign by the immune system; can be parts of pathogens like bacteria or viruses.