Thomas

=__How the immune system works?__=

__7 - Important Keywords__

 * ====**Important Word**==== || ====**Definition**==== ||
 * ====Pathogen==== || ====A microorganism that causes diseases.==== ||
 * ====Phagocyte==== || ====A non-specific type of cell that engulfs bacteria.==== ||
 * ====White Blood Cell==== || ====A specific type of cell that takes down the bacteria that it has memorized.==== ||
 * ====Antibodies==== || ====White blood cells bind with antigen on bacteria which destroys the bacteria.==== ||
 * ====Specific==== || ====A cell with a memory of the pathogens/bacteria they have seen before.==== ||
 * ====Non-Specific==== || ====A cell without a memory of the pathogens/bacteria they have seen before.==== ||
 * ====Inflammation==== || ====The body starts to swell up to protect itself when being infected with pathogen.==== ||

__Lines of Defense__
====The immune system works by having 3 layers of defense. The barriers, Non-specific and specific. Firstly, the barriers consist of nose mucus, for the bacteria to get stuck in, skin, so the bacteria can't just go right in and lastly, the stomach acid, where the bacteria gets caught in. The non-specific line of defense consists of the phagocytes. Phagocytes attack bacteria by engulfing it in a process called 'phagocytosis'. Lastly, the specific line of defense consists of all the specific lymphocytes (T-Cells & B-cells).====

__Phagocytes__
====Phagocytes destroy bacteria through phagocytosis which is where the phagocyte finds bacteria through its receptors and then wraps around the bacteria creating a layer called the 'phagozone'. Then the phagocyte starts to engulf the bacteria and slowly devours it down while turning it into protein for the body.====

__Lymphocytes__
====Lymphocytes and created in the Lymph System and mature in the Thymus. Lymphocytes consist of T - Cells & B - Cells. There are 3 types of T - Cells, Cytotoxic, Killer & Helper. There are 2 types of B - Cells, memory cells and plasma cells. Cytotoxic & Killer T - Cells both fight by sending antibodies to destroy the bacteria Helper T - Cells activate the B - Cells and T - Cells. Memory B - Cells are the memory for the lymphocytes while plasma cells also create antibodies to fight off the infection.====