- Created by: Zoe
- Created on: 07-12-11 17:29
These are white blood cells that defend the body against specific diseases. Like phagocytes they circulate around the lymph and blood. Supplies of this type of white blood cells are held in specific lymphoid tissue.
B and T Cells
There are two main types of lymphocytes known as B Cells and T Cells and respond to antigens on the surface of bacteria or viruses. The lymphocytes response is known as the specific immune response.
These cells secrete antiboides which bind to complementary antigens on the surfaces of bacteria or viruses. By binding to the bacteria, they act as a label and allow phagocytes to recognise and destroy the cell.
Each B cell produces one specific antibody which will bind to only one specific antigen on the surface of a cell.
In early embryo development millions of B cells are created in the bone marrow.
These cells are produced in the bone marrow however they mature in the thymus gland. T cells have one specific antigen receptor on the surface that only binds to an antigen with complementary shape.
There are two types of T cells:
- T helper cells- once activated, they stimulate B cells to divide and be capable to produce antibodies.
- T killer cells- these destroy cells withi antigens on the cell surface membrane.
There is two sections to the specific immune response which is the primary immune response and the secondary immune response.
Primary Immune Response
1. Activation of T cells
The macrophage engulfs the bacteria which has antigens on their cell surface membrane. Peptides from the bacteria join to the…