Specific Immune System: Antibodies

What are antibodies

Antibodies are Y shaped glycoproteins that bind specifically to antigens on pathogens

What are antibodies made of

Four polypeptide chains two heavy chains and two light chains

What holds antibody chains together

Disulphide bridges

What is the constant region of an antibody

Region that is the same in all antibodies and binds to immune cell receptors

What is the variable region of an antibody

Region with a specific shape that binds to a specific antigen

What is the hinge region of an antibody

Flexible region that allows antibody to bind to multiple antigens

What is an antigen antibody complex

Complex formed when an antibody binds to its specific antigen

What is the main function of antibodies

To bind specifically to antigens on pathogens

What is agglutination

Clumping together of pathogens by antibodies

Why is agglutination useful

It makes pathogens easier for phagocytes to engulf

What are opsonins

Antibodies that tag pathogens making them easier to recognise by phagocytes

What is neutralisation of toxins

Antibodies binding to toxins to make them harmless

What are antitoxins

Antibodies that neutralise toxins

How do antibodies prevent infection

They block pathogen attachment sites preventing entry into host cells

How do antibodies help phagocytosis

They act as markers making pathogens easier for phagocytes to identify

What happens when antibodies bind pathogens

They form antigen antibody complexes that neutralise or mark pathogens