4.1 Communicable diseases Flashcards
tuberculosis
bacteria- myobacterium
bacterial meningitis
bacteria
ring rot- plants
bacterium
HIV/AIDS
virus
influenza
virus
tobacco mosaic virus- plants
virus
black sigatoka- plants
fungus
blight- plants
protoctistan
ringworm
fungus
athlete’s foot
fungus
malaria
protoctistan
what is malaria caused by?
a person with malaria has gametes of plasmodium in blood
female anopheles mosquito sucks blood
plasmodium develops goes to salivary glands
bites an uninfected person
goes to liver, then blood (repeats)
physical plant defenses against pathogens
cellulose cell wall lignin thickening waxy cuticles bark stomatal closure callose
primary defenses against pathogens in animals
the skin blood clotting and skin repair mucous membranes inflammation antibodies in tear fluid
How does antibody structure help its function?(7)
2 light chains and 2 heavy chains / 4 polypeptide
chains ;
variable region allows , binding / attachment , to
antigen ;
two variable regions allow binding of more than
one (of the same) antigen ;
variable region on different antibodies allows specificity
to different antigens ;
constant region allows , recognition by / attachment to / binding to , (named) phagocytes ;
hinge (region) allows flexibility ;
disulfide , bonds / bridges , hold , polypeptides / light
and heavy chains , together ;
What is neutralisation?
cover / block , binding site / antigen / receptor site (on
pathogen) ;
bind to toxins ;
prevent , binding / entry , to (host) cell ;
What is agglutination? (2)
clump / bind together , (many) pathogens ;
(clump) too large to , enter (host) cell / cross
membranes ;
increase likelihood of being consumed by (named)
phagocyte
state four means of transmission.
direct physical contact
faecal-oral transmission
droplet infectoin
spores
what are opsonins?
proteins that bind to antigen on pathogen and allow phagocytes to bind
how do phagocytes engulf pathogens? 5
recognises pathogens on antigen
cytoplasm extends around pathogen engulfing it
pathogen now contained in phagosome
a lysosome containing diestive enzymes fuses with phagosome
phaocyte presents pathogens antigens on its
what are the 4 types of lymphocytes, and their functions?
killer- attack and kill host body cells displaying foreign antigens
helper - release cytokines stimulating B cels to develop and stimulate phagocytosis
regulator- shut down immune response
memory- long term immunnity
what are secondary non specific defenses in the body? ((3)
opsonins (bind to one antigen on the pathoen and allow phagocytes to bind)
neutrophils
macrophages
what are the 5 steps of the specific immune response?
infection of pathogen presentation of antigens clonal selection clonal expansion differentiation
What is herd vaccination?
vaccinating almost all of population (80-85%)
What is rin vaccination?
vaccinating people in immediate vicinity
What is the difference between active and passive immunity?
active= immune system is activated and produces own antibodies passive= when antibodies are passed on to individual through breast feeding or innjection
what is the difference between natural and artificial immunity?
natural= immunity achieved through normal life processes artificial= immunity achiived as result of medical intervention
What is the role of callose?
large polysaccharide that blocks sieve tubes
describe the steps of phagocytosis. (5)
pathogen recognised pathogen enulfed trapped in phagosome lysosomes fuse with phagosome digestion
What is the difference in role of B and T lymphocytes?
B lymphocytes manufacture antibodies
T lymphocytes release cytokines
What is meant by the term “vaccination”? (2)
artificial introduction of antigenic material
which stimulates the immune response
distinguish between the primary defenses and secondary defenses in mammels. (2)
primary defences prevent pathogen from entering the body
secondary defences attack the pathogen once its in the body
mast cells release histamine. What does histamine do?
cause vasodilation
capillaries more permeable to white blood cells
