Describe the symptoms of HIV
Which type of tumour is not cancerous?
Benign - as it is not capable of spreading to other rissues
Explain what a parasite is
Parasites live on or inside other organisms and cause them harm by damaging their cells
How can measles be prevented?
By having a vaccination
Usually given as a Mumps, Measles and Rubella (MMR) vaccine
What is a vector?
An organism that spreads a pathogen or parasite to another organism
What is a benign tumour?
A mass of cells dividing uncontrollably but the mass of cells stays in one location
It does NOT invade other tissues
Describe how measles is spread
An infected person cough or sneezes
This releases viral particles in droplets into the air
An uninfected person inhales the droplets containing the viral particles
What is meant by the term metastasis?
The ability for cells to break off a tumour and spread in the blood to a different location
What is meant by the term health?
Health is the state of physical and mental wellbeing
Does a correlation prove that one variable causes the change in the other variable?
Correlations do not prove cause or effect
They ONLY show a pattern between the 2 data sets
Describe the problems with using mosquito nets help prevent the spread of malaria
Not everyone has access to mosquito nets
Some people do not want to use them as they find them claustrophobic
State 2 examples of causal mechanisms that have been proven scientifically
The effects of diet, smoking and exercise on cardiovascular disease.
Obesity as a risk factor for Type 2 diabetes.
The effect of alcohol on the liver and brain function.
The effect of smoking on lung disease and lung cancer.
The effects of smoking and alcohol on unborn babies.
Carcinogens, including ionising radiation, as risk factors in cancer.
Explain what causes the symptoms of gonorrhoea
The bacteria produce toxins that cause harm to the cells
Describe the symptoms of gonorrhoea in women
- unusual green/yellow vaginal discharge
- pain when urinating
- painful and tender lower abdomen
- bleeding between periods
Describe 4 general ways in which diseases can be reduced or prevented
Isolating infected individuals
Define the term pathogen
Describe 3 ways in which pathogens can be spread
Definition of pathogen
A micro-organism that causes a disease e.g. bacteria, fungi
Spread of pathogens
- Water e.g. cholera
- Air e.g. measles, influenza
- Direct contact e.g. HIV, athlete's foot
Describe how malaria is spread Hint: 5 stages
The female mosquito feed on the blood of an infected person
The female mosquito then feeds on another uninfected human or infected animal
The protists are transferred from the mosquito's saliva into the uninfected person/animal's blood
The protist travels to the liver of the human/animal
The protist reproduces inside the liver cells damaging the liver cells and also in the red blood cells causing them to rupture as well.
What are the two types of tumour?
State the two categories that diseases can be divided into
Why is gonorrhoea harder to treat that salmonella?
The bacteria that causes gonorrhoea has become resistant to penicillin
Describe how gonorrhoea can be treated
Take antibiotics usually penicillin
Why do bacteria make us feel ill?
They produce waste products which are toxins for humans
These toxins damage cells and tissues
Why are cancer survival rates improving?
Increases medical advances
Being able to diagnose cancers earlier
Increased screening programmes
Improved public awareness of early signs & symptoms
How can HIV be spread?
Through unprotected sexual contact
By exchanging bodily fluid e.g. drug users exchanging contaminated blood when sharing needles
HIV can also be passed from mother to the unborn fetus
How do viruses make us feel ill?
They cause our cells to rupture
The damage to the cells causes the symptoms that we feel
What is a communicable disease?
A disease that can be passed from one an infected human or animal to an uninfected human
What is cancer?
The uncontrolled growth and division of cells which form a tumour
What are protists?
What is a positive correlation?
As one variable increases the other variable increases
What causes malaria?
protist (single-celled eukaryotic cell)