B3 Disease Flashcards
What is health?
Health is not just an absence of disease but a state of physical and mental wellbeing
What are non-communicable diseases?
Not passed from one person to another and not caused by a pathogen
What are examples of non-communicable diseases?
Depression, cancer, asthma, cardiovascular disease
What are similarities between bacteria and viruses?
Both pathogens
Both rapidly reproduce inside the body
Cause the majority of communicable diseases in humans
What are the differences between bacteria and viruses?
Bacteria divide by binary fission and produce toxins and poisons that make you feel ill
Viruses are smaller than bacteria and live and reproduce inside body cells damaging or destroying them
What type of disease is measles?
Viral
What are symptoms of measles?
Fever, red skin, rash, blindness, brain damage, death
How is measles transmitted?
Inhalation of droplets from coughs and sneezes
How is measles treated?
No treatment but can be vaccinated against it
What is a communicable disease?
Can be passed from person to person
What are examples of communicable diseases?
Flu, cold, measles, smallpox, influenza
What type of disease is HIV?
Viral
What are symptoms of HIV?
Flu-like symptoms, damages immune system
How is HIV spread?
Sexual contact and exchanging of bodily fluids
How can HIV be prevented and treated?
Can be prevented by using condoms and preventing sharing of needles
Antiretroviral drugs can help prevent developing AIDs
What type of disease is salmonella?
Bacterial
What are symptoms of salmonella?
Fever, cramps, vomiting, diarrhoea
How is salmonella transmitted?
Eating raw food or food prepared in unhygienic conditions
How is salmonella prevented and treated?
Food must be cooked correctly and poultry are now vaccinated against it.
What type of disease is gonorrhoea?
Bacterial
What are symptoms of gonorrhoea?
Pain while urinating, green/ yellow discharge
How is gonorrhoea transmitted?
Unprotected sexual contact with an infected person
How is gonorrhoea prevented/ treated?
Antibodies
What type of disease is athletes foot?
Fungal
What are symptoms of athletes foot?
Itchy foot, rash
How is athletes foot spread?
Contact with infected particles or skin
How can athletes foot be prevented and treated?
Antifungal drugs
How are common diseases spread?
Coughing/ sneezing, sharing of needles, through water, contact with the disease on surface/ in air, faeces, sexual contact
What are the 3 main ways pathogens are spread?
Air, direct contact, water
How do you prevent spread of airborne diseases?
Wash hands frequently, use a tissue, sneeze into elbow or handkerchief
How do you prevent spread of diseases by direct contact?
Don’t share needles, use condoms
How do you prevent spread of diseases through water?
Make sure food is cooked, don’t use open sewers, make sure water is clean
What is tobacco mosaic virus and how is it spread?
Viral disease which causes a mosaic pattern on the leaf, causing less photosynthesis and reduced growth
Spread by contact between diseased plant material and healthy plants and insects can also transmit
Can be controlled using TMV resistant strains as well as good field hygiene and pest control
What is rose black spot and how can it be spread?
Fungal disease which causes purple or black spots on leaves, leaves can turn yellow and drop early. Weakens the plant by reducing area for photosynthesis.
Fungal spores are spread by wind and water and can be treated by removing and burning infected leaves as well as using fungicides.
What is malaria?
The result of a single celled parasite called a protist. It spends part of its time in a human and part of its cycle in a female mosquito. The protist reproduce sexually in the mosquito and asexually in humans. The mosquito carries the parasite which means it is a vector of the disease. The female lays her eggs by feeding on human blood which is when the protist is passed onto the human. The protist is carried in the blood and infects the liver first and then red blood cells.
What are the symptoms of malaria?
When the protist bursts out of the red blood cells, symptoms of shaking and fever are caused and can be fatal
What are ways to prevent malaria?
Antimalarial medicines, insect repellents, mosquito nets, long sleeved clothing
What is a vector?
An animal which carries a disease
What are microorganisms?
Bacteria, fungi, viruses, protists. They need food, water and warmth to grow
What is the aseptic technique?
Incubate at 25 degrees C to reduce the chance of growing any pathogens which can be harmful to humans
How do we calculate bacteria at the end of a growth period?
Bacteria at beginning x 2 ^ number of divisions
What are vaccines?
Contain a small amount of dead or weakened pathogen
What is herd immunity?
When a large proportion of a population are immune to a disease
What are the bodies natural defence mechanisms?
Skin, lungs, stomach, eyes
Skin
Forms a protective outer barrier and produces secretions to destroy bacteria
Lungs
Trachea secretes mucus which traps pathogens and the cilia move the mucus back up to be swallowed
Stomach
Contains hydrochloric acid to destroy microorganisms in mucus, food and drink
Eyes
Produce tears to destroy microorganisms
What do pathogens do?
Reproduce and make toxins which destroy the body’s cells and make you feel unwell
What are painkillers?
Relieve the symptoms of an infection but do not kill the pathogen
How do white blood cells destroy pathogens?
Phagocytosis
Antitoxin production
Antibody production
What is phagocytosis?
The engulfing of microbes. Phagocytes engulf the microbes and break them down once they are inside the cell. The microbe is destroyed by powerful digestive enzymes, which are released within the cytoplasm of the white blood cell
What is antibody production?
Lymphocytes can release antibodies which attach to an antigen on a microbe, leading to the microbe’s destruction
What is antitoxin production?
Antitoxins neutralise the effects of toxins
What is active immunity?
Comes from the body creating antibodies to a disease either by exposure to the disease or by vaccination
What is passive immunity?
Antibodies given to you by another organism e.g breast milk
What is primary response?
A vaccine with a weakened form of measles virus results in the production of memory cells and antibodies
What is secondary response?
When exposed to the virus naturally and infected, an individual can produce a higher amount of antibodies
What are antiseptics?
Kill micro bodies in the environment
What are antibiotics?
Interact with cell wall of the bacteria meaning the bacteria will burst and get destroyed, does not affect eat your own cells
Does not work on viruses as they take over your own cells
What are characteristics of drugs?
Dose
Efficacy
Toxicity
What are the 4 stages of drug testing?
Computer modelling
Testing on cells and tissues
Testing on animals
Clinical trials
What is a placebo?
A dummy drug which is given to some participants of the trial instead of a real drug
What is a double blind trial?
A trial where neither the patient nor the doctor knows who is getting the placebo or who is getting the real drug
