B2 COPY Flashcards
What is a communicable disease?
A communicable disease is a disease which can spread between organisms.
What is a non-communicable disease?
A non-communicable disease is a disease which cannot spread between organisms.
What are the 4 types of pathogens?
BACTERIA
FUNGI
PROTISTS
VIRUSES
How can communicable disease be transmitted?
- Water
- Air
- Body fluids
- Animals
- Soil
- Food
What does the human defence system consist of?
PHYSICAL
-Respiratory system lined with mucus to stop pathogens
-Skin as a barrier to pathogens
CHEMICAL
-Tears contain enzymes which brake down bacteria
-Stomach produces hydrochloric acid, which kills pathogens.
MICROBIAL
-if pathogens are able to pass through the human defences, they have to compete with bacteria already living in gut.
How can white blood cells protect us from pathogens?
CONSUME THEM
PRODUCE ANTIBODIES
PRODUCE ANTITOXINS
How does a white blood cell produce antitoxins? What happens?
- When white blood cells come across foreign antigens on pathogens, they produce antibodies specific to the antigen
- The white blood cells divide so that more can be produced
- The antibodies can disable the pathogen so they can be engulfed
- Some white blood cells stay around. Memory Cells.
How can the spread of disease be reduced in animals?
-Being hygienic Sterilising wounds -Living in clean conditions -Killing infected animals -Isolating infected animals -Vaccination
What is vaccination?
Vaccination is infecting a weak or dead disease into you, so you have white blood cells which can easily detect it and destroy it if the disease comes round again.
What are the pros of vaccination?
Help prevent once very common communicable diseases.
What are the cons of vaccination?
Don’t always give you immunity.
Can be expensive.
What techniques can be used to identify diseases?
- Counting number of cells in a sample
- Observing the symptoms
- Growing the sample
- Viewing the sample under a microscope.
How can you grow bacteria in a lab?
- Hot agar jelly poured into a plastic dish
- Microorganisms planted onto dish.
- The microorganisms then grow and multiply.
What are aseptic techniques?
Aseptic techniques are used to prevent contamination of unwanted organisms.
What are monoclonal antibodies? How do you make them?
- Produced from clones of white blood cells.
1) Inject animal with antigen
2) White blood cells produced against the antigen making lots of antibodies.
3) Blood taken
4) Cells fused with tumour cells, which cause them to divide rapidly, producing lots of the antibody.