4.1.1 communicable diseases and the immune system Flashcards
what is a pathogen
an organism that causes disease by taking nutrition from another organism or causing it harm
what does parasitic mean
organisms that live in or on a host and take their nutrition
what is fungi
eukaryotic
non-pathogenic
parasitic
release spores and multiply via budding
grow under skin
what is a virus
akaryotic (non-living)
uses cell’s nucleus to multiply
what is a protoctista
eukaryotic
non-pathogenic
parasitic
require a host
release toxic waste
what is bacteria
prokaryotic
non-pathogenic
multiply by binary fission
release toxic waste
what is tuberculosis
bacteria
kills cells and tissues and affects respiratory system
what is HIV/AIDs
virus
attacks immune system
what is influenza
virus
attacks respiratory system and causes muscle pain/headaches
what is tobacco mosaic virus
virus
discoloured leaves
what is blight
protist
affects leaves and potatoes
what is black sigatoka
fungus
leaf spots on banana plants that reduce yield
what is ringworm
fungus
growth in skin causes rash
what is athlete’s foot
fungus
growth under skin in feet
what is ring rot
bacteria
ring of decay in vascular tissue
what is malaria
protist
parasite in blood causes fever then death
what is bacterial meningitis
bacteria
infection of meninges (membranes around brain and spinal cord)
what is direct transmission
when communicable diseases are passed along by direct contact
what are examples of direct transmission
direct physical contact
faecal-oral transmission
droplet infection
spore transmission
what are the passive physical plant defences
cellulose cell wall
lignin thickening of cell walls
waxy cuticles
bark
stomatal closure
what is a callose
polysaccharide deposited in the sieve tubes to restrict entry of pathogens
what is a tylose
a swelling that fills xylem vessels that stops passage of water
what necrosis
cells are killed to prevent the spread of infection
what is a canker
produced by death of cambium creating a sunken lesion
what are the chemical plant defences
terpenoids
alkaloids
tannins
pheromones
hydrolytic enzymes
defensins
what does non-specific mean
fast acting
same for any infection
provides a general defense against most threats