B5 Infection and response Flashcards
(51 cards)
What is health
A state of physical and mental wellbeing, not just an absence of disease
What is a communicable disease
An infectious disease caused by pathogens
What is a non-communicable disease
A disease that is not infectious
What factors affect health
Diet
Stress
Life situations e.g gender, ethnic group
What is a pathogen
A bacterium, virus, or other microorganisms that cause infectious disease in living things, including plants
What are bacteria
Single-celled organisms that reproduce by binary fission
Environmental decomposers
Pathogenic bacteria are the minority
What do bacteria do
Cause the majority of communicable diseases
May produce toxins
May directly damage cells
What do viruses do
Cause disease in every type of organism
What are viruses
Small, regularly-shaped pathogens that live and reproduce in cells, damaging and destroying them
How are pathogens spread
Droplets
Direct contact
Water
What do bacteria need to grow
Culture medium (carbohydrates - energy, nitrogen - protein production)
Warmth (some)
Oxygen (some)
How should petri dishes be stored
Upside down to stop condensation dripping
Why should petri dishes be partially secured with tape
Stops air from contaminating bacteria and vice versa
Stops the growth of anaerobic bacteria
In school labs, at what temperature should bacteria be stored
25C and under
In school labs, why is there a limit on the temperature that bacteria can be stored
Reduces the risk of pathogens growing
What is an antiseptic
A substance used on living surfaces to destroy microorganisms
What is an antibiotic
A drug used to kill microorganisms in the body
What is a disinfectant
A substance used on non-living surfaces to destroy microorganisms
What affects the rate of bacterial growth
Temperature
Available nutrients
Oxygen levels
pH
How is the number of bacteria (end of growth) calculated
Number of bacteria (start of growth) * (2^number of divisions)
What is the zone of inhibition
The area where microorganisms have been killed or cannot grow
What did Ignaz Semmelweis do
Insisted doctors washed their hands before delivering babies
Helped to reduce the rate of death from childbed fever
What did Louis Pasteur do
Claimed that microorganisms cause disease
Developed vaccines from anthrax and rabies
What did Joseph Lister do
Encouraged the use of antiseptic chemicals so pathogens were destroyed before they could cause infection
