B7 Non-communicable diseases Flashcards
What is a tumour?
a lump of cells formed as a result of uncontrolled cell division
Benign tumour
a growth of abnormal cells (usually within the membrane) that is non-invasive and therefore not cancerous
How can benign tumours be dangerous?
If it causes pressure or damage to an organ
Malignant tumour
a fast-growing tumour that is cancerous and can invade and spread to other areas of the body
How do malignant tumours spread?
it splits up, releasing small clumps of cells into the bloodstream or lymphatic system. They are carried to different parts of the body where they may lodge in another organ. Then they continue their uncontrolled growth and form secondary tumours
Causes of cancer
genetic risk factors, mutations caused by carcinogens, ionising radiation, and some viruses
Two main ways of treating cancer
radiotherapy and chemotherapy
Radiotherapy
cancer cells are destroyed by targeted doses of radiation
Chemotherapy
chemicals are used to either stop the cancer cells dividing or make them ‘self-destruct’
Carbon monoxide
a poisonous gas found in tobacco smoke which takes up to 10% of the blood’s oxygen carrying capacity
Smoking during pregnancy
if the mother’s blood is carrying carbon monoxide, the fetus may not get enough oxygen to grow properly
Effects of tar
a toxic compound found in tobacco smoke. The build of tar in the delicate lung tissue can lead to a breakdown in the structure of the alveoli, causing COPD. This reduces the surface area to volume ratio of the lungs. Tar is also a carcinogen
Effects of smoking on the heart
smoking narrows the blood vessels of the skin. Nicotine makes the heart rate increase and other chemicals damage the lining of the arteries, increasing the risk of coronary heart disease.
Effects of exercise on health
more muscle tissue means a higher metabolic rate, so you are less likely to be overweight. This reduces the risk of arthritis, diabetes, and high blood pressure. Exercise lowers your blood cholesterol levels and helps balance the different types, reducing the risk of heart disease
In type 2 diabetes your body either doesn’t make enough…
insulin to control your blood sugar levels or your cells stop responding to insulin
After an alcoholic drink, the ethanol…
is absorbed into the blood from the gut and passes easily into the body tissues, including the brain
What is cirrhosis of the liver?
a disease caused by alcohol that destroys the liver tissue. The active liver cells are replaced with scar tissue that cannot carry out vital functions
Alcohol is a carcinogen so heavy drinkers are at increased risk of developing…
liver cancer
Effects of alcohol on the brain
In some alcoholics, the brain becomes so soft and pulpy that the normal brain structures are lost and it can no longer function properly
Effects of alcohol in pregnancy
If a pregnant woman drinks, the alcohol is passed across the placenta into the baby. The developing liver cannot cope with alcohol, so the development of the brain and body can be badly affected
How does ionising radiation cause cancer?
the radiation penetrates the cells and damages the chromosomes, causing mutations in the DNA
Well-known sources of ionising radiation
UV light from the sun, radioactive materials found in soil, water and air, medical and dental x-rays, and accidents in nuclear power generation
