Disease Flashcards
(24 cards)
What is a pathogen?
A pathogen is a harmful organism which invades the body and causes disease – it is a cell that causes harm/disease to the body.
What are infectious diseases caused by?
Pathogens
What is an infectious disease?
An infectious disease can be transmitted from person-to-person – a disease that can be easily caught.
What are the symptoms?
Symptoms are indicators of the disease – the physical effects of the disease.
What does it mean if the disease is vector-borne?
Animals transmit the disease.
What does it mean if the disease is vehicle-borne?
Object transmitting disease.
What is it called when a disease uses horizontal transmission?
People spread the disease
What is the mean when a disease uses vertical transmission?
Transmitted across the pla-centre.
Give ways in which diseases can be translated and examples.
In water – cholera bacterium Food - Salmonella bacterium Airborne - influenza virus Contact – Athletes foot fungus Body fluids – HIV Animal vectors: House fly - dysentery bacterium Anopheles mosquitoes - malarial protozoan.
How is malaria spread?
This disease is vector-borne. The female anopheles mosquito spread the protozoan parasite called a plasmodium. The plasmodium is released in to the blood stream when the mosquito uses its sharp proboscis to penetration the skin of the mammal and injects it with its saliva. In its saliva there is an anticoagulant to avoid the blood clotting; an anaesthetic to stop the mammal from feeling their sharp proboscis.
How does the plasmodium affect the body?
The plasmodium travels through the bloodstream to the liver so it can multiply and then passes through to the bloodstream. The plasmodium will invade the blood cells and make them burst and release poison into the bloodstream that cause the symptoms of malaria.
e.g. High Fever
What is an antibacterial?
An antibacterial is a substance that we spread on a surface (e.g. Hands) that prevent bacteria from multiplying.
What is an antibiotic?
A drug that is used to kill/stop them from multiplying. Usually taken orally.
What is an anti-fungal.
A substance that kills fungi.
What is an antiseptic?
A substance that are used to prevent bacteria from multiplying. This is normally used on cuts.
What is a bactericide?
A bactericide is a type of antibiotic that kills bacteria.
What is a bacteriostat?
A bacteriostat is an antibiotic that prevents bacteria from multiplying.
What is a virus?
A virus is a very small infectious organism that reproduce within the cells of living organisms (hosts) and often cause disease.
What is a bacteria?
A bacteria is a single-celled micro-organism which can either be free-living or parasites; they can cause disease.
Why do we have a layer of defence?
We use it to prevent pathogens from entering the body.
How does blood help with defence against pathogens?
Inside the blood there are things called platelets. Platelets are fragments of cells clot the blood to form scabs as a plaster to stop pathogens from entering the bloodstream.
What is the second line of defence against pathogens?
A phagocyte (a type of white blood cell) is the second line of defence. It engulfs and digests pathogens.
What is the third line of defence?
The Lymphocyte (a type of white blood cell) makes antibodies that clamp on to the bacteria that alerts the phagocyte that this is a pathogen. These antibodies will stick around to form an immunity to that certain amount of immunity against the bacteria for a while.
What is the first line of defence?
Skin- largest organ of the body, provides a barrier as long as the skin is not cut- physical
Sebum (oil in the skin)- produced by the sebaceous gland (oil and sebum), works as an antiseptic enzyme (lysozyme)- chemical
Eye (tear duct)- washes Bactria from eye, antiseptic enzyme (lysozyme)- chemical
Epithelial linings (mouth, nose, trachea)- this is used to waft mucus to the stomach to get rid of bacteria- physical
Stomach acid- contains hydrochloric acid (HCl) very acidic, a mucus lining, kills pathogens- chemical.
Nose- mucus traps bacteria/dust, hair traps large dust particles- physical.
Microbes on skin/in gut- friendly bacteria takes up all of the space, it out competes the harmful bacteria- biological
