B8: Defending Ourselves Against Disease Flashcards
What causes an infectious disease?
A microorganism entering and attacking the body.
How do bacteria make you ill?
> Binary fission
Toxins
Directly damage cells
How do viruses cause disease?
They take over body cells, damaging and destroying them.
3 ways to stop infection in hospitals
> Hand washing
Disinfectants
Better cleaning
4 ways that diseases are spread
> Droplet infection
Direct Contact
Contaminated food and drink
Breaks in the skin
What are the body’s natural defences against disease?
> Skin
Blood clotting
Mucus
Stomach acid
3 roles of White Blood Cells
> To ingest microorganisms
To produce antibodies
To produce antitoxins
3 viruses to be immunised against
> Polio
Measles
Whooping Cough
3 bacterial infections to be immunised against
> TB
Tetanus
Diphtheria
Why do antibiotics have no effect on viruses?
Because viruses reproduce inside cells.
Do antibiotics work on bacteria or viruses?
Bacteria
1 example of antibiotic resistant bacteria
MRSA
How does a vaccine work?
- Small amounts of dead/inactive pathogen are put into the body.
- White Blood Cells produce antibodies and quickly fight off the weakened pathogen.
- In the future, if the pathogen enters the body again, the White Blood Cells can quickly reproduce the antibodies.
Agar
The nutrient jelly on which many microorganisms are cultured.
Why do we sterilise lab equipment?
To kill bacteria already on them so that they don’t grow and contaminate cultures.