Infection And Response Flashcards
What is the definition of health?
A state of physical and mental well-being, not just the absence of disease.
What are communicable diseases?
Diseases that are infectious and can be passed from one person to another. They are caused by pathogens.
What is a non communicable disease?
A disease that cannot be transmitted from one person to another such as arthritis.
How does bacteria cause disease?
Divide rapidly by splitting in two (called binary fission). The produce toxins (poisons) that affect your body and make you feel ill. Sometimes directly damage the cells.
How do viruses cause disease?
Take over the cells of your body. They live and reproduce inside the cells, damaging and destroying them.
How are pathogens spread?
- by air, including droplet infection = if you are ill, you expel tiny droplets of pathogens when you cough, sneeze or talk. Other people breathe in the droplets, and so the infection spreads.
- direct contact = the contact of an infected organism with a healthy one, common in plants. In people direct contact means direct contact of skin such as sexually transmitted diseases. This means the pathogens could also be transmitted by cuts, scratches and any access to blood.
- water = fungal spores carried in splashes of water often spread plant diseases. For humans, eating raw, undercooked, or contaminated food, or drinking water containing sewage can spread diseases such as diarrhoeal diseases, cholera, or salmonellosis. The pathogen enters your body through the digestive system.
What are pathogens?
Microorganisms including bacteria, viruses, fungi and protists.
What did Ignaz Semmelweis discover?
He was a doctor in the mid-1850s. Many women were dying at the hospital from childbed. The medical students and doctors would dissect and work on dead bodies before delivering the babies without washing their hands in between. Semmelweis encourages students and doctors to wash their hands in between, and cases fell immediately. The disease was being passed to the mums from the dead.
What did Louis Pasteur develop and discover?
He showed that microorganisms cause disease. He developed vaccines against diseases such as anthrax and rabies.
What did Joseph Lister discover?
He started to use antiseptic chemicals to destroy pathogens before they caused infection in operating theatres.
How does hygiene prevent the spread of pathogens?
- hand washing after toilet, before cooking, or after contacts with an animal or someone who has an infectious disease
- disinfectants on kitchen work surfaces, toilets etc. To reduce the number of pathogens.
- coughing or sneezing into a handkerchief, tissue or your hands (and then washing your hands)
- maintaining hygiene of people and agricultural machinery to help prevent the spread of plant diseases.
Why does isolating infected individuals reduce the risk of pathogens and infection?
The fewer healthy people who come into contact with the infected person, the less likely it is that the pathogen will be passed on. This is also true of plants infected with diseases but it is only possible with smaller plants that can be moved and destroyed easily.
How can destroying/controlling vectors help reduce the spread of pathogens?
Some diseases are passed to others via vectors, for example malaria. If the vectors are destroyed,the spread of disease can be prevented. By controlling the number of vectors, the spread of disease can be greatly reduced.
How does vaccination help reduce the spread of pathogens?
Vaccinations re when a small amount of a dead or inactive form of the pathogen is introduced to your body. As a result, if you come into contact with a live pathogen your immune system will be prepared and you will not fall ill. However, it cannot protect plants against disease as they do not have an immune system/
How is measles spread?
The inhalation of droplets from coughs or sneezes.
What are the symptoms of measles?
Fever and red skin rash.
How is HIV/AIDS spread?
Sexual contact or the exchange of bodily fluids such as blood. It can also be spread from mother to child in breast milk.
What are the symptoms for HIV/AIDS?
Mild, flu-like illness to begin with.
How is Tobacco Mosaic Virus spread?
Direct contact and vectors.
Where do salmonella live?
In the guts of many different animals.
Where is salmonella found (in food)?
Raw meat, poultry, egg,, and egg products such as mayonnaise.
What are the symptoms of salmonella?
Fever, abdominal cramps, vomiting and diarrhoea.
How is gonorrhoea spread?
sexually transmitted disease (STD).
What are the symptoms of gonorrhoea?
Thick yellow or green discharge from the vagina or penis on urination.
How is gonorrhoea treated?
Antibiotics
What is Rose Black Spot?
A fungal disease of rose leaves.
What are the symptoms of rose black spot?
Black or purple spots to develop on the leaves. Leaves can turn yellow and drop early. This weakens the plant because it reduces areas of the leaves that carry out photosynthesis.
How is rose black spot spread?
Wind and wate.
What is malaria caused by?
Parasitic protists.
How is malaria spread?
Through the bite of infected female mosquitoes.
How does your skin prevent microorganisms from getting into your body?
It acts as a physical barrier to stop bacteria and viruses from reaching the tissues beneath. If you have a cut or damage the skin, your body restores it. Your skin also produces antimicrobial secretions to destroy pathogenic bacteria. Healthy skin is covered with microorganisms that help keep you healthy and act as an extra barrier to the entry of pathogens.
How does your nose prevent microorganisms from entering your body?
Your nose is full of hairs and produces a sticky liquid called mucus. The hairs and mucus trap particles in the air that may contain pathogens or irritate your lungs. If you spend time in an environment with lots of air pollution, the mucus you produce when you blow with your nose is blackened, showing that the system works.
