Answers
what are the two type of defence mechanisms? - Accurate answers specific, non specific
what are two types of non specific defence mechanisms? - Accurate answers physical barrier
(skin), phagocytosis
what are two types of specific defence mechanisms? - Accurate answers cell mediated response,
humoral response
what is an antigen? - Accurate answers part of a substance that is recognised as non-self by
immune system and triggers immune response
How can T cells identify invader cells from normal cells? (4 ways) - Accurate answers a phagocyte
(that has carried out phagocytosis) present a pathogens antigens on its surface, body cells (who have
been invaded by a virus) present viral antigens on their surface, transplanted cells have different
antigens on their surface, cancer cells present antigens on cell surface
what is the main difference between cell-mediated immunity and humoral immunity? - Accurate
answers T lymphocytes only respond to antigens on a body cell, B cells respond to antigens found in
blood/tissue fluid
what are the 4 different functions of a cloned T cell? - Accurate answers memory cell, stimulate B
cells to divide, stimulate phagocytosis, cytotoxic T cells
How do cytotoxic T cells kill infected cells? - Accurate answers Produce perforin, make holes in cell
surface membrane, becomes freely permeable to all substances, dies
How does an antibody lead to the destruction of a cell? - Accurate answers agglutination of
bacterial cells makes it easier for phagocytes to locate and destroy, act as markers for phagocytes to
destroy cells they are attached to