the structure and function of antibodies Flashcards
(13 cards)
What type of protein are antibodies?
Quaternary
What does the basic structure of an antibody consist of?
Four polypeptide chains (2 heavy and 2 light) joined together by disulfide bonds
What does each antibody have?
A constant region and a variable region
What is in the constant region?
The sequence of amino acids that is the same in all molecules of the same type of antibody
What is in the variable region?
Different antibody molecules which are specific to different antigens
What do the variable regions of the heavy and light chains form?
Two antigen binding sites
What do these sites have?
Specific tertiary structure complementary to the antigen molecules they attach to
What do antibodies not do?
Destroy the pathogen
What are the processes antibodies cause?
Agglutination of antigens, stimulation of phagocytosis
What does agglutination refer to?
The clumping together of cells possessing the antigen
What does the antibody use to do this?
Its 2 antigen binding sites
How does this help to destroy the pathogen?
It makes them easier to be phagocytised
What do phagocytes have to destroy antigens?
Receptors in their cell surface membrane
