b5 Flashcards
communicable diseases
What is a communicable disease?
a disease that can be transmitted from one organism to another
What is a pathogen?
a microorganism that causes disease
Name four types of pathogen
bacteria, fungi, protists, viruses
How can pathogens spread?
air, water, direct contact
How do bacteria make you ill?
produce toxins that damage tissues
How do viruses make you ill?
reproduce rapidly inside cells, damaging or destroying them
Name three examples of viral diseases.
measles, HIV, tobacco mosaic virus
Name two examples of bacterial diseases.
salmonella, gonorrhoea
Name four methods of controlling the spread of communicable disease.
good hygiene, isolating infected individuals, controlling vectors, vaccination
Describe an example of a protist disease.
malaria – caused by a protist pathogen that is spread
from person to person by mosquito bites, and causes
recurrent fevers
Describe an example of a fungal disease in plants.
rose black spot – spread by water and wind, and
affects plant growth by reducing a plant’s ability to
photosynthesise
How can the cause of a plant disease be identified?
gardening manuals and websites, laboratory testing, monoclonal antibody kits
What are three mechanical defences that protect plants?
thorns and hairs, leaves that droop or curl, mimicry to trick animals
Give three physical defences of plants.
cellulose cell walls, tough waxy cuticles, bark on trees
How can aphids be controlled by gardeners?
introduce ladybirds to eat the aphids
