How Our Bodies Defend Themselves against Infectious Diseases Flashcards
What is a pathogen?
Microorganisms that cause disease.
How do bacteria and viruses make us feel ill?
Reproduce in the body damage cells and release toxins.
How do white blood cells help to defend against pathogens?
Ingest pathogens and destroy them, produce antibodies and antitoxins.
How does immunity develop?
Antigens - unique proteins on a pathogen cell surface, white blood cells produce antibodies to join up with antigens on a pathogen.
What impact did Semmelweiss’ research have?
He made the doctors wash their hands in chlorine water. There was a huge decrease in the number of deaths.
How are painkillers useful?
They relieve symptoms of an infection or illness.
What are antibiotics are what can they be used for?
Are medicines that work inside the body to kill bacteria that cause diseases by damaging the bacterial cells.
What is one of the impacts of the overuse of antibiotics?
Overuse of antibiotics can cause resistant bacteria to develop.
Why is it so difficult to treat viral infections?
Viruses live inside body cells.
HT-Only. How do individual pathogens develop resistance?
During antibiotic treatment less resistant bacteria killed first, more resistant bacteria remain and will re-infect if full course of antibiotics not taken.
Describe the action vaccinations on the body?
Given a weak/dead form of the pathogen. White blood cells (WBC’s) produce antibodies. Pathogen is destroyed.
What does the MMR vaccine protect people against?
MMR vaccine is used to protect against measles, mumps and rubella.
Why must petri dishes be sterilised before use?
To kill any microorganisms already on the dishes.
When using inoculating loops to transfer bacteria what must be done to avoid contamination?
The loop must be heated in a flame.
Why must petri dishes be taped shut?
To stop microorganisms getting in or out.
