Biology - 7 Non-Communicable Diseases

Lifestyle factors affecting disease [3]

• smoking

• lack of exercise

• eating

Substances affecting disease [3]

• ionising radiation

• UV light from the sun

• secondhand tobacco smoke

Correlation

a suggested link or relationship between variables

Causal mechanism

something that explains how one factor influences another

Tumour

a mass of cells that continue to grow and divide without any obvious function in the body

Benign tumour

A tumour that does not affect surrounding tissues other than by physically crowding them - contained within a membrane - non-cancerous

Malignant tumour

A cancerous tumour that splits and may invade the bloodstream or lymphatic system, from which they may lodge in another organ. Disrupts normal tissues

Cancer risk factors [4]

• genetic risk factors

• mutations from carcinogens

• ionising radiation

• viral infections

Cures for cancer [2]

• Radiotherapy

• Chemotherapy

Radiotherapy

Cancer cells are destroyed by targeted doses of radiation. Can also destroy healthy cells

Chemotherapy

Chemicals are used to either stop cancer cells dividing or make them 'self-destruct'.

Carbon monoxide effects

Bonds to haemoglobin thereby interfering with oxygen transport in the bloodstream. Causes headaches in humans at low concentrations, can cause death with prolonged exposure at high concentrations.

Smoking during pregnancy [reason + 3]

not enough oxygen supplied for growth

• premature births

• low birthweight

• stillbirths

What happens to the cilia of the lungs when smoking?

They are anaesthetised by chemicals and so do not sweep away mucus and bacteria. The mucus buildup causes coughing.

The effects of tar

Accumulates in lungs, makes smokers more likely to develop bronchitis. Destroys alveoli causing chronic obstructive pulmonary disease (COPD)

What heart-related diseases are linked to smoking? [2]

• Cardiovascular disease (heart attacks, strokes)

• Coronary heart disease

How does smoking increase the risk of heart problems? [5]

• smoking narrows blood vessels

• nicotine increases heart rate

• other chemicals damage the lining of arteries

• chemicals also raise blood pressure

• increases risk of clots and various diseases

Health problems from being obese: [3]

• type 2 diabetes

• high blood pressure

• heart disease

if you exercise more…

…you are less at risk of these health problems

1st - muscle tissue - causal mechanism for exercise keeping you healthy [4]:

• more muscle tissue

• higher metabolic rate

• less likely to be overweight

• reduces risk of arthritis, diabetes, high blood pressure

2nd - the heart - causal mechanism for exercise keeping you healthy:

• heart will be fitter and have better blood supply

• exercise lowers blood cholesterol

• reduces risk of fatty deposits on coronary arteries

• lowers risk of heart disease etc

With type 2 diabetes, your body either…

• doesn’t produce enough insulin or

• doesn’t respond to insulin

insulin

a hormone that allows you to use glucose for energy

type 2 diabetes affects [4]:

• circulation

• kidney function

• eyesight

• may eventually lead to death

Risk factors for type 2 diabetes [4]:

• being overweight

• lack of exercise

• being older

• genetic tendency

cure for type 2 diabetes [3]:

• balanced diet with controlled carbohydrate

• losing weight

• regular exercise

The effects of alcohol [3]:

• absorbed into blood from gut and passes into body tissues

• affects nervous system

• can lead to unconsciousness, coma and death

How does alcohol affect the nervous system?

Makes thought processes, reflexes and many reaction slower.

Liver cirrhosis

A disease that destroys the liver tissue. The tissue is replaced by scar tissue that cannot carry out vital functions

Liver cancer

Alcohol is a carcinogen, and can cause liver cancer, which spreads quickly and is difficult to treat

Brain damage

Alcohol causes the brain to become soft and pulpy, losing normal brain structures and stopping it from functioning properly

Effects of drinking while pregnant [5]

• miscarriage

• stillbirth

• premature births

• low birthweight

• fetal alcohol syndrome

How does ionising radiation cause cancer?

Radiation penetrates cells and damages chromosomes, causing DNA mutations

Sources of ionising radiation [4]

• UV light from sun (sunscreen and clothing)

• radioactive materials in soil, water and air

• medical and dental X-rays

• accidents in nuclear power generation

melanoma

a type of skin cancer from sun exposure