Microbes And Defence Against Disease Flashcards
What are communicable diseases
Can be passed from one organism to another
What are non communicable disease
Cannot spread from one organism to another
Examples of communicable diseases
Covid
Cold
Flu
Measles
AIDS
Mumps
Chicken pocks
Examples of non communicable diseases
Diabetes
Cancer
Asthma
Heart disease
Anaemia
Stroke
Cardiovascular disease
What are the three main types of microbes
Fungi
Bacteria
Viruses
Structure of fungi
They have a spare case and network of threads forming a structure called a mycelium
Why is fungi dangerous and what illnesses can it cause
It’s dangerous bc it’s responsible for athletes foot infection, ringworm and thrush
Also can spoil food
Things to do to prevent athletes foot
Avoid sharing towels, shoes, socks, clothing
Avoid use of public pools, toilets and showers
Wear footwear in public
How can fungi be useful
Yeast is a fungus used in the baking and brewing industry and cheese industries
What are pathogens
Microorganisms that cause disease
What’s the structure of a virus
Have a head capsule containing DNA with a long tail and an end plate attached. They reproduce inside host cells until they burst open
Why are viruses dangerous
Cause diseases like the flu, chickenpox, mumps and AIDS. Flu viruses can change into many different forms meaning that you cannot be immune to the flu
How can viruses be useful
Humans can make use of viruses bc they help in genetic engineering
Bacteria structure
cocci are spherical in shape, bacilli are rod shaped, spirochetes are spirals. Some may have a long filament called a flagellum attached - this allows them to move.
How are bacteria dangerous
Bacteria are responsible for numerous illnesses including: MRSA, Salmonella and Tuberculosis. They also cause food to go “off”. Bacterial infections can be treated with antibiotics
How are bacteria useful
Some are very useful to humans - e.g. for the production of yoghurt, treating sewage and in genetic engineering
How are pathogens spread?
- direct contact= This can be sexual contact during intercourse or non-sexual contact, like shaking hands.
- water= Dirty water can transmit many diseases, such as the cholera bacterium.
-air= When a person who is infected by the common cold sneezes, they can spray thousands of tiny droplets containing virus particles to infect others.
- unhygienic food preparation = Undercooked or reheated food con cause bacterial diseases like Escherichia coli which is a cause of food poisoning.
-vector= Any organism that can spread a disease is called a vector. Many farmers think tuberculosis in their cattle con be spread by badgers.
What is aseptic technique
To study bacteria and other microbes effectively, scientists must stick to a set of rules referred to as aseptic technique. This allows them to ensure that the bacteria they are looking at have come from one single source.
Aseptic technique involves the use of sterile equipment
Examples of equipments used for aseptic technique
Autoclave- like a big pressure cooker
Scientists will wear white coats- this is to stop bacteria from their clothes contaminating the samples. They will be taken off before leaving the lab
What is an outbreak
An outbreak is a sudden rise in the number of cases of a disease. An outbreak may occur in a community or geographical area, or may affect several countries. It may last for a few days or weeks, or even for several years.
Example of an outbreak
Influenza
What’s an epidemic
An epidemic occurs when an infectious disease spreads rapidly to many people through a large area eg a country
Example of an epidemic
In 2003, the severe acute respiratory syndrome (SARS) epidemic took the lives of nearly 800 people worldwide.
What’s a pandemic
A pandemic is a global disease outbreak. It differs from an outbreak or epidemic because it:
• affects a wider geographical area, often worldwide.
• infects a greater number of people than an epidemic.
• is often caused by a new virus or a strain of virus that has not circulated among people for a long time. Humans usually have little to no immunity against it. The virus spreads quickly from person-to-person worldwide.
• causes much higher numbers of deaths than epidemics.
• often creates social disruption, economic loss, and general hardship.
