CELL MEDIATED RESPONSES

Question 1

what are the two types of WBCs

Answer 1

phagocytes (neutrophils and macrophages)
lymphocytes (T and B lymphocytes and memory cells)

Question 2

where do t lymphocytes mature

Answer 2

thymus gland

Question 3

what are the subgroups of T cells

Answer 3

helper t
cytotoxic t

Question 4

what do t lymphocytes recognise

Answer 4

antigens presented by macrophages

Question 5

describe the cell mediated response

Answer 5

1. Phagocytosis & phagocyte presents
   antigens (from pathogen) on membrane.
2. Helper T cell receptor binds to antigens &
   is activated (release cytokines).
3. Activated helper T cell divides quickly
   (mitosis- clonal expansion) and forms
   clones of genetically identical cells.
4. Cloned cells respond to the pathogen in
   different ways-
   Stimulate more phagocytes 🡪 more
   phagocytosis
   Develop into memory cells 🡪 quicker
   response for secondary infections
   Stimulate B cells to multiply & release
   antibodies
   activate cytotoxic T cells

Question 6

what do cytotoxic t cells do

Answer 6

bind to infected cells
perforin makes holes in infected cells membrane and enzyme enters
infected cell is destroyed