B2 - health matters and cancer

• health is a state of physical and mental wellbeing
• Some of the factors affecting physical and mental health are:

  -diet

  -stress levels

  -drugs (alcohol, nicotine; medicine, antibiotics)

  -genetics, cholesterol levels

  -excersize/ physical activity
• A risk factor is a variable that increases the likelihood of a particular disease, but does not guarantee that the person will develop it
• A causal mechanism is the way in which something increases the risk of a disease
• What are some of the human and financial cost of ill health


  -poor physical health increases the likelihood of poor mental health

  -cost of treatment is increasing

  -financial impact on families due to ill health
• An example and effect of defects in the immune system

  -HIV infects white blood cells and stops them from working properly

  -increases the likelihood of other communicable diseases e.g. cold or flu
• An example and effect of viral infections

  -HPV can damage the cervix in women

  -Increased likelihood of cervical cancer in women
• An example and effect of immune response to pathogens


  -white blood cells responding to pathogens can lead them to respond to other substances incorrectly e.g. pollen

  -allergic reactions such as hay fever , skin rashes and asthma
• New cells are made for growth and to repair damaged tissue or replace dead cells
• In order for a new cell to be made, the DNA is copied inside an existing cell and the cell then divides so that there are two cells
• A mutation is when a mistake is made when the DNA is being copied

  Most of the time the mutation has no effect

  However sometimes a cell has a lot of mutations enabling it to grow and divide in an uncontrolled manner producing too many cells - tumour
• The chance of a mutation can be increased by

  -smoking

  -UV radiation

  -x-rays
• Characteristics of a benign tumour


  -cells are contained with one area inside a membrane

  -cells do not invade other parts of the body

  -not cancerous
• Characteristics of a malignant tumour


  -cells are not within a membrane

  -cells break of and spread over to other parts of the body via the blood

  -cancerous