The Immune System Flashcards
Define antigens
Molecules that generate an immune response found on the surface of cells
Definition of pathogens
Why do they generate an immune response?
Organisms that cause disease
They contain forge in antigens on their surface
Define toxins
Poisons that are molecules not cells that are produced by bacteria
Why can’t an organ from another human be transplanted to any human?
Cells of individuals of the same species do not contain the same antigens
Another organ has foreign antigens which causes a rejection of transplanted organs
Define phagocyte
Where are phagocytes found
Type of white blood cell that undergoes phagocytosis which is the engulfment of pathogens
In the blood and tissue
Outline the steps of phagocytosis
Phagocyte recognizes foreign antigen on pathogen
Cytoplasm of phagocyte engulfs pathogen
Phagocytic vacuole fuses with pathogen
Lysosomes containing lysozymes fuse with Phagocytic vacuole, breaking down and digesting pathogen
Phagocyte presents pathogens antigens on surface - antigen presenting cell - to activate other immune system cells
How are clone T cells produced?
Where are helper T cells produced
Helper T cell has receptor proteins which are complementary to phagocyte antigens
Stimulates division via mitosis
Thymus gland
What are the clone T cells?
Phagocyte
Cytotic T cell
B cell
Memory cell
What does the cytotic T cell do?
Releases perforin to put holes in pathogen membrane
Why are B cells advantageous?
They are covered in antibodies complimentary and specific to antigen on pathogen
These antibodies form an antigen antibody complex with antigen
How do B cells bind to signaling molecules released by T helper cells?
They have receptor proteins on the surface
What happens when the antibody of a B cell meets an antigen?
What is this process called?
B cell is activated and divides via mitosis into plasma cells
This process is called clonal selection
What is the name of an antibody released by a plasma cell
Monoclonal antibody
Describe agglutination
Antibodies bind to 2 specific antigens simultaneously to slow down the pathogen and make it easier for phagocytes to engulf bacteria
Antibodies produce markers which stimulates phagocytosis
What is an antibody a type of?
What does the specificity of an antibody depend on?
Why are they unique?
Protein
Depends on variable regions which form the binding site
Variable regions have a unique tertiary structure due to different amino acid sequence
