Immune System

Immune System
The first defender in immune system is white blood cells.

Just as an army has soldiers with different jobs, body has different types of white blood cells to defend against invaders.

All white blood cells are known as leukocytes. They travel swiftly though human body to challenge intruding pathogens.

Two kinds of white blood cells, or leukocytes, are called lymphocytes. These are either B-cells or T-cells.

These are either B-cells or T-cells. Each one has a special job.

B-cells produce protective proteins called antibodies. These antibodies attach themselves to certain substance on pathogens celled antigens and mark them so that other cells will destroy them later.

Antibodies also block flu virus from moving from one cell to another. This limits the spread of infection within the body.

B-cells can produce up to 10 millions copies of the needed antibody in one hour.

The job of T-cells is to coordinate the attack on pathogens. T-cells do this by giving instructions to other immune cells on when and how to attack.

These immune cells then produce different kinds of molecules that carry information and instructions form one group of immune cells to another.

These messenger molecules tell other cells when to change their behavior and coordinate the immune response.
Immune System