B7 - Non-communicable Diseases Flashcards
What is cancer?
the common name for a malignant tumour, formed as a result of changes in cells that lead to uncontrolled growth and division
What are carcinogens?
agents that cause cancer or significantly increase the risk of developing cancer
What is a causal mechanism?
something that explains how one factor influences another
What is correlation?
an apparent link or relationship between two factors
What is ionising radiation?
has enough energy to cause ionisation in the materials it passes through, which in turn can make them biologically active and may result in mutation and cancer
What is a tumour?
a mass of abnormally growing cells that forms when the cells do not respond to the normal mechanisms that control growth and when control of the cell cycle is lost
What is a non-communicable disease?
A disease that cannot spread from one person to another
What are risk factors for diseases?
- Aspects of your lifestyle such as smoking, lack of exercise, or overeating
- Substances that are present in the environment or in your body such as ionising radiation, UV light from the sun, or second-hand tobacco smoke
- Age
- Genetic makeup
Why do scientists need to do research before declaring a correlation of 2 things as a causal mechanism?
They have to do lots of research as it may just be a correlation but not actually a causation
What are the impacts of non-communicable diseases?
Every serious disease has an impact on human life. Local communities are often tasked with supporting and looking after those who are ill, this could also have a financial cost as if a wage-earner becomes ill they will not be able to work. Diseases also cost nations huge sums of money treating those who are ill and the loss of money when people are not working
What % of disease related deaths are non-communicable?
70%
What are the 2 types of tumours?
- malignant
* Benign
What are benign tumours?
Benign tumours are growths of abnormal cells contained in one place, usually within a membrane. They do not invade other parts of the body, however they can grow very large, very quickly and as a result they can pressure or damage an organ. This can be life-threatening
What are malignant tumours?
A malignant tumour can spread around the body, invading healthy neighbouring tissue. Malignant tumours may split up, releasing small clumps of cells into the bloodstream or lymphatic systems. They then spread to new parts of the body and cause new secondary tumours. The growing tumours often completely disrupt normal tissues and if left untreated, will kill the person.
How are tumours formed?
Tumours are formed when control of the cell cycle is lost and the cells grow in abnormal, uncontrolled ways
What are the causes of cancer?
- Genetics
- Carcinogens
- Ionising radiation
- Viral Infections
How does Genetics cause cancer?
Some cancers, such as breast cancer and ovarian cancer, can be caused by genetics
How do Carcinogens cause cancer?
Chemicals called carcinogens can cause mutations in cells that trigger the formation of tumours. An example of this is asbestos and the tar in tobacco smoke
How does Ionising radiation cause cancer?
Ionising radiation, such as UV light and X-rays, can interrupt the normal cell cycle and cause tumours to form. For example, melanomas appear when there is uncontrolled growth of pigment-forming cells in the skin as a result of exposure to UV light from the sun
How do Viral Infections cause cancer?
About 15% of human cancers are caused by virus infections. For example, cervical cancer is a result of infection by HPV. Teenagers in the UK are now routinely vaccinated against the virus
Why is cancer difficult to treat?
It spreads around the body
What are the 2 treatment methods for cancer?
- Chemotherapy
* Radiotherapy
What is chemotherapy?
Chemotherapy is when chemicals are used to either stop the cancer cells dividing or to make them “self-destruct”. There are many different types of chemotherapy and scientists are working to make them as specific to cancer cells as possible
What is radiotherapy?
Radiotherapy is when the cancer cells are destroyed by targeted doses of radiation. This stops mitosis in the cancer cells but also damages the healthy cells around the cancer cells. Methods of delivering different types of radiation in very targeted ways are improving cure rates
What is the addictive, but fairly harmless, drug found in tobacco?
Nicotine
Why do people like to smoke?
Nicotine produces a sensation of calm, well being, and “being able to cope”
What is a harmful gas found in tobacco smoke?
Carbon Monoxide (CO)
Why do smokers get more breathless then non-smokers?
After smoking a cigarette, up to 10% of the blood will be carrying carbon monoxide rather than oxygen. This can lead to a shortage of oxygen causing the smoker to be breathless. Tar in the smoke also causes a breakdown fo the structure of teh alveoli
What can smoking during pregnancy cause?
- Premature births
- Low birthweight
- Stillbirths
Why does smoking during pregnancy cause issues?
During a pregnancy a mother is carrying oxygen for her developing fetus as well as herself. If the mothers blood is carrying carbon monoxide, the fetus may not get enough oxygen to grow properly
What does tobacco smoke contain?
- Nicotine, which is an addictive substance in the smoke
- Carbon Monoxide, a toxic gas, which replaces oxygen in the red blood cells
- Tar, which is a sticky black substance that accumulates in the lungs and is also carcinogenic
- Chemicals that anaesthetise the cilia in the airways and prevent them wafting up the mucus
How many stillbirths are there in the UK each year?
3500
How many stillbirths in the UK are caused by smoking?
20%, 700
How are chemicals in tobacco smoke harmful?
the cilia in the trachea and bronchi that move mucus, bacteria, and dirt away form the lungs are anaesthetised by some of the chemicals. They stop working for a time, allowing dirt and pathogens down into the lungs and increasing the risk of infections. Mucus also builds up over time and causes coughing
How is tar in tobacco smoke harmful?
Tar is a sticky, black chemical that that accumulates in the lungs, turning them from pink to grey. Tar makes smokers much more likely to develop bronchitis. The build-up of tar in the delicate lung tissue can lead to a breakdown in the structure of the alveoli, causing chronic obstructive pulmonary disease (COPD). This reduces the surface area to volume ratio of the lungs, leading to severe breathlessness and eventually death. Tar is also a carcinogen. It acts on the delicate cells of the lungs and greatly increases the risk of lung cancer developing. Tar also causes other cancers of the breathing system, for example, larynx and trachea
How does smoking affect your chances of getting cardiovascular disease?
The chemicals in tobacco smoke also effect the heart and blood vessels. Scientists have data showing that smokers are more likely to suffer from cardiovascular problems than non-smokers. They have also worked out that this is a causal mechanism, not just a correlation
How does smoking increase your chances of getting cardiovascular disease?
Smoking narrows the blood vessels in your skin, ageing it. Nicotine makes the heart rate increase whilst other chemicals damage the lining of the arteries. This makes coronary heart disease more likely, and it increases the risk of clot formation. The mixture of chemicals in cigarette smoke also lead to an increase in blood pressure. This combination of effects increases the risk of suffering cardiovascular disease, including heart attacks and strokes
What happens if you eat more food than you need?
If you eat more food than you need, the excess is stored as fat. You need some body fat to cushion your internal organs and act as an energy store. However, over time regularly eating too much food will make you overweight and then obese.
What can obesity lead to?
- Type 2 diabetes
- High blood pressure
- Heart disease
What is type 2 diabetes?
in type 2 diabetes, either your body does not make enough insulin to control your blood sugar levels or your cells stop responding to insulin. This can lead to problems with circulation, kidney function, and eyesight, which may eventually lead to death.
What are risk factors for type 2 diabetes?
- Being overweight or obese
* Not doing much exercise
How can people restore their normal blood glucose balance if they have type 2 diabetes?
- Eating a balanced diet with controlled amounts of carbohydrate
- Losing weight
- Doing regular exercise
How does exercise keep you healthy and reduce the chance of getting cardiovascular disease?
Doing exercise causes you to have more muscle tissue, increasing your metabolic rate, so you are less likely to be overweight. Your heart will be fitter and develop a better blood supply. Regular exercise lowers your blood cholesterol levels and helps the balance of the different types of cholesterol. This reduces the chances of fatty deposits building up on your coronary arteries, so lowering your risk of heart disease and other heart problems
What do people who exercise regularly have compared to those who dont?
- bigger muscles
- fitter hearts
- bigger lungs
What is alcohol?
A commonly used social drug that is poisonous, however the liver can usually remove it before it does any permanent damage. Alcohol is also very addictive
What happens after you drink alcohol?
After drinking alcohol, the ethanol is absorbed into the blood from the gut and passes easily into the body tissues, including the brain. It affects the nervous system, making thought processes, reflexes, and many reactions slower than normal. In small amounts alcohol makes people feel relaxed, cheerful, and reduces inhibitions. Larger amounts lead to lack of self-control and lack of judgement. If the does of alcohol is too high, it can sometimes lead to unconsciousness, coma, and even death
What organs does alcohol mostly affect?
- Brain
* Liver
What permanent damage can alcohol cause?
- They may develop cirrhosis of the liver, a disease 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 an increased risk of developing liver cancer. This usually spreads rapidly and is hard to treat
- Long-term heavy alcohol sue also causes damage to 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. This can lead to death
What happens when a pregnant woman drinks alcohol?
If a pregnant woman drinks alcohol, it passes across the placenta into the developing baby
What can drinking alcohol during pregnancy cause?
- Miscarriage
- Stillbirths
- Premature births
- Low birth weight
- Fetal Alcohol Syndrome
What is Fetal Alcohol Syndrome?
If a mother drinks during pregnancy, the baby may have facial deformities, problems with its teeth, jaw or hearing, kidney, liver and heart problems, and may have learning and other developmental problems. This is known as Fetal Alcohol Syndrome (FAS)
How does ionising radiation cause cancer?
ionising radiation is a well known carcinogen. Ionising radiation penetrates the cells and damages the chromosomes, causing mutations in the DNA.
What are well known sources of ionising radiation?
- UV light from the sun
- Radioactive material
- Medical and dental x-rays
Why does drinking during pregnancy cause problems?
The developing liver of a baby cannot cope with the alcohol, so the development of the body and brain of an unborn baby can be badly affected, especially in the early stages of pregnancy
How much alcohol is safe to drink during pregnancy?
Doctors are unsure of how much alcohol is safe to drink during pregnancy but they recommend to not drink any to avoid FAS
Describe how the balance between mass of food eaten and the amount of exercise a person does controls body mass:
If a person eats more food, their energy intake will increase. If a person exercises more, more energy will be released during respiration and used for muscular contraction. If someone’s energy intake is greater than the amount of energy transferred during respiration, the persons body mass will increase as the excess energy will be stored as fatty deposits. If someone’s energy intake is the same as the amount of energy transferred during respiration, the persons body mass will stay the same. If someone’s energy intake is less than the amount of energy transferred during respiration, the persons body mass will decrease as the glycogen in the muscles and fatty deposits are used as an energy store.
