Communicable Diseases Flashcards
How do viruses make you ill?
Reproduce inside cells which are then damaged
Why do bacteria make you ill?
They produce poisons thay damage tissues and make you feel ill
3 ways pathogens can be spread
Touching, Water, Air
Four types of pathogens
Virus, bacteria, protists and fungus
Measles - type, symptoms, how it’s spread
Viral disease, symptoms of fever and a red skin rash, complications can be fatal. Spread by inhalation of droplets from sneezes and coughs.
HIV
Initially causes flu like illness, unsuccessfully controlled with antiretroviral drugs the virus attacks the bodies immune cells. Spread by sexual context or exchange of bodily fluid (e.g. blood) Reproduces in white blood cells which are destroyed
AIDS
Occurs when the bodies immune system become so badly damaged from HIV it can no longer deal with other infections or cancers (other pathogens)
Tobacco mosaic virus
Plant pathogen affecting many species like tomatoes. It gives a mosaic pattern of discolouration on the leaves which affects growth due to lack of photosynthesis because of the disease effecting chloroplasts meaning a lack of them means less light absorbed so less photosynthesis so fewer molecules to make new cells by mitosis
Salmonella
Symptoms include fever, abdominal pain, vomiting and diarrhoea caused by toxins. It is spread by bacteria ingested from food, or food prepared on unhygienic surfaces.
Gonorrhoea
An STD with symptoms of a thick yellow/green discharge from the genital area, bleeding between periods and pain on urinating. Was treated well with antibiotic penicillin until many resistant strains appeared. Spread by unprotected oral, anal and vaginal sex.
Rose black spot
Black fungal disease where purple or black spots develop on leaves which often turn yellow and drop early. It affects growth of the plant as photosynthesis is reduced. It is spread in the environment by water or wind. Can be treated using fungicides or removing and destroying affected leaves.
How does rose black spot affect growth rate of plants
It destroys the chloroplasts so it can’t absorb as much light, which means less photosynthesis so it can’t grow as fast because it has less energy and less glucose,cellulose and proteins made meaning less mitosis.
Malaria
Caused by protists, the protist has a life cycle including the mosquito. Symptoms are recurrent episodes of fever and can be fatal. The spread of malaria is controlled by preventing the vectors, mosquitos from breeding and using mosquito nets to avoid being bitten and using insect repellent in homes.
Skin preventing pathogens
Prevents pathogens entry into the body
Mucus preventing pathogens
Linings traps dirt and microbes so they can’t properly get into the body
What is phagocytosis
When a white blood cells engulfs (surrounds and takes in) a pathogen and destroys it
Antibodies
Pathogens have chemical substances on its surface called antigens which are unique to that microbe, our white blood cells detect the antigens and make antibodies which attach to the surface of the microbes and make them harmless.
Antitoxins
Work in exactly the same was as the antibodies but attaches to the toxin and neutralises it
How do vaccines work?
A vaccine contains a weakened form of a pathogen. When the vaccine enters the body white blood cells produce antibodies. Some of these white blood cells stay in the blood. If the person is attacked by the real pathogen the white blood cells can produce antibodies more quickly and in bigger numbers. This means the person will not feel ill.
What is the advantage of vaccinating a large proportion of the population against measles?
It means less people will get infect and there is less risk of spreading because most will be immune
Antibiotics
Antibiotics are medicines that help cure bacterial disease by killing infective bacteria inside the body. Specific bacteria has to be treated with specific antibiotics. Penicillin is an antibiotic discovered by Alexander Fleming. Some diseases develop resistance to antibiotics
Painkillers
Don’t destroy pathogens only reduce symptoms of the disease (e.g. paracetamol and aspirin)
The heart drug digitalis originated from where
Foxgloves
The painkiller aspirin originates from where
Willow
What does toxicity mean
The amount a substance can be poisonous/toxic and harm animals
Efficacy meaning
The ability to produce a desired of intended result
Dosage meaning
How much of a drug should be given
Pre clinical trials (1)
Done on animals or tissue to test for toxicity
Clinical trial (2)
Done on healthy volunteers to test for toxicity
Clinical Trial (3)
Done on small number of patients with the disease to test for toxicity, efficacy and dose
Clinical Trial (4)
Done on large number of patients with the disease to test for efficacy and dose
How can diet, smoking and exercising an affect the risk of cardiovascular disease
If your diet had too much saturated fat in it it can increase your cholesterol which increases your chance of getting coronary heart disease. Being overweight also means your heart has to work harder which leads to high blood pressure. Smoking makes the lining of your vessels rough which makes it easier for things to block up in them
Type 2 diabetes
This is when you are not able to react to insulin. Obesity increases the risk of getting type 2 diabetes because it rises your glucose level and means you have more fat in your body so your insulin resists and may end up tiring your pancreas. The cost of this on the NHS is 10%
Effects of alcohol on unborn babies
If their mothers are drinking during pregnancy they tend to be born prematurely which comes with lots of potential complications
Symptoms of lung disease
Breathlessness, tiredness and terrible effects on lungs
What is a tumour
When cells divide very rapidly and unnaturally and create a mass of tissues
Difference between benign and a malignant tumour
A benign tumour is non cancerous and grow locally and cannot spread by invasion. Whereas malignant tumours are cancerous and invade neighbouring tissues and enter blood vessels.