4.1.1 Communicable diseases, disease prevention and immune system
Description
AS - Level Biology (MODULE 4: Biodiversity, evolution and disease) Mind Map on 4.1.1 Communicable diseases, disease prevention and immune system, created by alexjrea on 12/04/2016.
(e) (i) the structure and mode of action of phagocytes (ii) examination and drawing of cells observed
in blood smears
(f) the structure, different roles and modes of action of B and T lymphocytes in the specific immune
response
T helper cells
T killer cells
T regulatory cells
B plasma cells
memory cells
(b) the means of transmission of animal and plant communicable pathogens
Direct transmission
droplet infection
coughing and sneezing
sexual intercourse
e.g HIV
touching an infected organism
e.g Athlete's foot
Indirect transmission
air
water
food
vector
e.g malaria- mosquitoes are vectors that spread plasmodium
(c) plant defences against pathogens
waxy cuticle provides a physical barrier
plant cells are surrounded by cell walls
produce a polysaccharide called callose which makes it harder for pathogens to enter
cells. At the plasmodesmata it limits the spread of viiruses between cells