B2.3 - How can we prevent the spread of infection? Flashcards
List 5 ways you can reduce the spreading of diseases
- cleaning and covering wounds
- clean water free of pathogens
- good personal hygiene
- keeping food in the fridge
- clean utensils and surfaces
What is an epidemic?
If a disease affects many individuals in a population, this is an epidemic.
Only one region e.g ebola in West Africa
What is a Pandemic?
If a disease spreads over a very wide geographical area it is a pandemic.
Affects many countries e.g covid 19
Why is it important to protect plants from the spread of diseases?
Diseases will kill the plants
Food chain relies on plants.
Plants are habitat for organisms
What is polyculture?
Growing a mixture of DIFFERENT plants
What is monoculture?
Growing many of the SAME kind of plant close to each other.
Is polyculture or monoculture better for preventing the spread of disease in plants?
Polyculture
Disease doesn’t spread as rapidly as different plants are affected differently by certain pathogens.
What is crop rotation and how does it prevent the spread of disease in plants?
Growing different plants in the same plot of soil in rotation. eg growing carrots in a certain area then growing potatoes in that same area after the carrots have be harvested.
The soil will contain pathogens from the old crops and can infect the new crop. Growing a different type of crop means there’s a chance it won’t be affected by the pathogen
Give an example of chemical control ( Chemical substance used to prevent spreading of disease )
Spraying Pesticide on plant to kill the pathogen
Give an example of biological control (Introducing new species into the system)
New species is introduced to the crop.
The new species is a predator of the of the pest that spreads the disease.
e.g using ants to eat the pest
What is a vaccine?
Substance that contains dead/inactive pathogens
create immunity to the certain pathogen.
How do vaccines work? What do they contain?
Dead pathogen enters body.
White blood cells respond and product specific antibodies to fight pathogen.
White blood cell remembers how to make the antibody and can rapidly produce it if infected by the pathogen before symptoms can show.
Are vaccine an example of passive or active immunity
Active ( body creates its own antibodies)
What is an example of passive immunity? What is 1 advantage and 1 disadvantage of this
Sick person is injected with antibodies needed.
(antibody is not made in own body)
Quick :)
Immunity doesn’t last long :(
another example is mother breastfeeding milk that contains the antibodies to their baby
How do white blood cells respond to vaccines?
Produce antibodies for the pathogen inside the vaccine
Advantage and disadvantage of Vaccines?
Long lasting immunity :)
Take long to work :(
What is the difference between direct and indirect transmission
Direct - spread from one host to another e.g ill person sneezes on another person and they get ill.
Indirect - a second organism that is unaffected by the pathogen transfers it to a new host e.g mosquito spreading malaria to a human
What are disinfectants?
Substance used to kill pathogens on NON-living things
e.g Fairy liquid on plates
What is antiseptic
Antimicrobial substances that are applied to LIVING tissue/skin to reduce the possibility of infection
e.g hand sanitiser
Name 3 of the antiseptic techniques
- Sterilising Petri dish before use
- passing equipment through a Bunsen burner flame to kill bacteria e.g wire loop
- lifting the lid of the Petri dish as little as possible to prevent unwanted microorganisms entering the dish.
How can you tell you’re sick?
You feel symptoms (coughing, sneezing vomiting)
If the doctor can’t tell from your symptoms what is wrong, what will they do?
Collect a sample of fluid or tissue from sick person
Sample is tested to identify the pathogen
Name 4 of the sampling and identification techniques
- Counting Cells
- Microscopy and staining
- Cell Culture
- Genome Analysis
What is counting cells?
Cells in a sample counted under a microscope using grid method
determine how many cells in sample
compare to healthy amount
