Download - Immunity
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B1a 4.6 Immunity
Immunity
Lesson objectivesTo describe how the immune system works.
To evaluate how vaccination can help prevent some bacterial and viral diseases.
B1a 4.6 Immunity
WHAT VACCINATIONS HAVE YOU HAD?
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B1a 4.6 Immunity
What vaccinations have you had?
• Diphtheria • Tetanus• Whooping cough (pertussis) • Polio• Hib: vaccination against the bacteria Haemophilus influenzae type B,
which can cause meningitis, • Measles • Mumps • Rubella (German measles) • Meningitis C • Pneumococcal: vaccination against the bacteria Streptococcus
pneumoniae (known as pneumococcus), which can cause meningitis.
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B1a 4.6 Immunity
Immune system
• Every cell has unique proteins on its surface called antigens.
• As we have covered your white blood cells recognise antigens on pathogens as different.
• Your white blood cells make antibodies to attack and kill the pathogens.
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B1a 4.6 Immunity
The diseases that children are commonly vaccinated against were once childhood killers.
B1a 4.6 Immunity
Immune system
• White blood cells are able to remember the right antibody needed to tackle a particular pathogen.
• Immunity happens because next time you meet the pathogen the white blood cells quickly produce the correct antibody.
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B1a 4.6 Immunity
Immune system
• You become ill the first time you meet a new pathogen.
• This is because it takes time to find the right antibody. With future infections your body destroys all the invaders before you can become ill.
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B1a 4.6 Immunity
Vaccination.
• Some pathogens are dangerous because they can kill you before your body makes the right antibodies.
• These days we can protect ourselves against such diseases by immunisation (vaccination)
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B1a 4.6 Immunity
This is how vaccines protect you against dangerous infectious diseases
Small amounts of dead or inactive pathogen are put into your body, often
by injection..
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B1a 4.6 Immunity
This is how vaccines protect you against dangerous infectious diseases
The antigens in the vaccine stimulate your white blood cells into making antibodies.
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B1a 4.6 Immunity
This is how vaccines protect you against dangerous infectious diseases
You are immune to future infections by the pathogen. This is because your body can respond rapidly and
make the correct antibodies as if you had already had the disease.
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B1a 4.6 Immunity
This is how vaccines protect you against dangerous infectious diseases
B1a 4.6 Immunity
Key word splat.
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antibody antigen
antibiotic Anti toxin
pathogen White blood cell
ingest