Biology - Non communicable disease

• non-communicable disease


  a disease not capable of being spread from one person to another
• Risk factor


  something that increases the likelihood of developing disease or injury
• poor diet (over eating or under eating)

  depresses the body's immune system, leading to malnourishment, obesity, brittle bones and type 2 diabetes
• smoking


  Causes lung disease, various cancers and coronary heart disease
• alcohol consumption


  Causes liver and kidney damage, mental health issues and preserves cells to kill them
• lack of exercise

  causes obesity, weakened muscles and reduced strength and heart disease
• unsafe sex


  Can cause pregnancy, HIV and other STIs and STDs
• financial costs of non-communicable diseases


  Diseases will have an economic impact if a wage earner becomes ill and cannot work. Tax payers often bear the cost of supporting people who are ill, formally through taxes. Disease costs nations huge sums of money by treating people and the loss of money earned when large numbers of the population are ill
• epidemiological studies


  Look for diseases that are caused by different risk factors and look at a large sample of people so the results are less likely to be due to chance and collect evidence to support or reject their link between the risk factor and the disease (they are looking for a correlation)
• Correlation does not equal causation


  Two conditions may appear together but not cause each other as it is illogical that they are linked and do not affect each other, as evidence is needed to back up the causation
• Cancer


  any uncontrolled growth or tumor caused by abnormal and uncontrolled cell division. Cell DNA is damaged during the multiplication of the cell and these cells can sometimes sneak through a checkpoint which then multiply to form a tumour.
• beneign tumour


  Tumours which grow and get bigger but do not affect any other parts in the area as the cells are contained in a membrane and do not actively affect any other tissues
• malignant tumour


  Tumours which are not contained in a membrane and spread which can actively work against other cells as they can be transported around the body through the bloodstream
• Well-known causes of cancer

  -smoking: tars in cigarettes

  -x-rays: UV radiation

  -uranium: radiation from nuclear waste

  -alcohol: preserves and damages cell DNA
• radiotherapy


  Cancer cells destroyed by a dose of radiation as mitosis of the cancer cells are stopped but can also damage healthy cells
• chemotherapy


  Chemicals are used to either stop the cells dividing or to make them 'self-destruct
• Mutation


  a random error in gene replication that leads to a change
• Carcinogen


  A cancer-causing substance
• Contents of a Cigarette


  Tar (mixture of chemicals including carcinogens), carbon monoxide and nicotine
• Heart disease


  Cardiovascular system works harder than it should as arteries are covered in fatty deposits and blood pressure increases
• Negative impacts of smoking


  -cardiovascular problems

  -increased risk of blood clots

  -increased heart rate and damage of artery lining

  -arteries are narrowed as fatty deposits build up on walls
• Smoking and the lungs


  Chemicals in cigarettes can anaesthetise the cilia in the trachea and bronchi which allows pathogens and dirt to enter the lungs and can cause an infection
• bronchitis


  inflammation of the bronchi when tar accumulates in the lungs turning them grey
• chronic obstructive pulmonary disease (COPD)


  Build-up of tar that leads to a breakdown in the structure of alveoli and reduces the surface area to volume ratio of the lungs leading to severe breathlessness and eventually death
• carbon monoxide poisoning


  Carbon monoxide binds with haemoglobin in red blood cells and takes up some of the oxygen carrying-capacity in the blood which leads to a shortage of oxygen
• Smoking and pregnancy


  A foetus relies on the mother for oxygen and if there is carbon monoxide is the mother's blood the foetus doesn't receive enough oxygen to develop properly. This can lead to low birth weights, premature births or still births
• What happens if you consume more energy than you use up?


  gained weight as excess calories are stored as fat around the body
• Why do you need body fat?

  -insulation

  -shock absorber

  -cushions organs

  -long-term energy store
• metabolic rate


  the rate at which the body uses energy (ie. the faster the metabolic rate the faster chemical reactions occur in the body which demands more energy)
• Benefits of exercise

  -controls weight

  -builds muscle tissue

  -releases endorphins

  -increases metabolism

  -enlarges lungs
• Problems with being overweight

  -increased risk of cardiovascular disease

  -fat in arteries

  -arthritis

  -type 2 diabetes

  -high blood pressure

  -low metabolic rate
• Benedict's test for diabetes


  If glucose is present then blue solution will turn from green through yellow to orange or brick red (qualitative test)
• Clinistix test for diabetes


  Checked colour against colour chart to find amount of glucose present in sample (quantitative test)
• type 2 diabetes


  Body cells do not respond to insulin or body does not produce sufficient insulin
• Liver disease caused by alcohol


  Cirrhosis of the liver as it breaks down alcohol and too much causes it to become poisoned with modules of dead cells
• Stomach disease caused by alcohol


  Alcohol causes erosion of the stomach
• Kidney disease caused by alcohol


  Too much alcohol leads to kidney failure as they are supposed to regulate the fluids in the body
• Heart disease caused by alcohol


  Alcohol can cause high blood pressure and heart failure
• alcohol and pregnancy

  -Alcohol can cause miscarriages, still births, premature births and low birthweights

  -developing livers cannot cope with alcohol like an adult liver

  -babies may be born with deformities and/or learning disabilities
• Alcohol impacts on the brain


  Brain becomes soft and pulpy so its structures are lost and can no longer function properly