Test

• Health


  • Physical health: Being free from disease, active, fit, sleeping well and no substance abuse
  • Mental health: Feeling good about yourself and being free of conditions such as depression and anxiety
  • Social health: Having healthy relationships, loving and being loved
• WHO


  World Health Organization – part of the UN responsible for monitoring global health
• Disease


  Any problem with the body not caused by injury
• Types of disease


  • Communicable diseases: Diseases caused by pathogens, can be passed on
  • Non-communicable diseases: Diseases caused by genes or lifestyle, cannot be passed on
• Correlated diseases


  Getting one disease increases your chance of another due to diseases weakening organ systems, damaged immune system, weaker defences
• Non-communicable diseases


  • Genetic disorders: Diseases caused by inheriting faulty genes from your parents
  • Malnutrition: Diseases caused by poor diet
  • Anaemia: Lack of iron, causes fewer and smaller red blood cells and low energy
  • Kwashiorkor: Lack of protein, swollen belly, small muscles, stunted growth
  • Rickets: Lack of calcium or vitamin D, causes weak bones leading to bowed legs
  • Scurvy: Lack of vitamin C, swollen bleeding gums, muscle and joint pain, lack of energy
• Ethanol


  The drug found in all alcoholic drinks
• Drugs


  Chemicals that change the way your mind and body works
• Cirrhosis


  A fatal liver disease caused by drinking too much alcohol over a long period of time
• Social problems of alcohol


  Missed work days, increased risk of other diseases, risky sexual behaviour, increased violence
• Obesity


  Being overweight to the extent that your health is at risk
• BMI


  Body mass index, over 30 = obese
• BMI calculation


  BMI = weight (kg) / height (m)^2
• Problems with BMI


  Someone with a lot of muscle could have high BMI without being obese
• Waist:hip ratio


  The ratio of waist width to hip width. Over 0.9 (women) or 1.0 (men) = obese
• Calculating waist:hip ratio


  Waist: hip ratio = waist width / hip width
• Cardiovascular disease


  Harmful substances in blood build up in the arteries around the heart. Blockages can form leading to heart attacks
• Stents


  Used to treat cardiovascular disease. A tube of metal mesh is fed into the narrowed artery and opened up, holding the artery open

  
• Treating heart disease with lifestyle


  More exercise and a better diet can treat cardiovascular disease, but this takes time
• Pathogen


  Microorganism that causes disease
• Types of pathogen


  • Bacteria
  • Virus
  • Protist
  • Fungi
• Tuberculosis


  Bacteria. Serious lung damage, bloody cough, fever
• Cholera


  Bacteria. Sever life-threatening diarrhoea
• Chalara ash dieback


  Fungi. Kills the leaves of ash trees, killing the tree
• Malaria


  Protist. Sickness, fever and weakness
• Haemorrhagic fever


  Virus, eg Ebola. Liver and kidney damage, internal bleeding
• HIV


  Human immunodeficiency virus attacks white blood cells, causing AIDS
• AIDS


  Acquired Immunodeficiency Syndrome. Weakened immune system making simple infections deadly. Caused by HIV
• Opportunistic pathogens


  Pathogens that live in us causing no harm, but become dangerous when given the opportunity, such as Helicobacter pylori which cause stomach ulcers
• Ways diseases spread


  • Airborne: Spreading through the air, such as colds and flu in infected droplets of saliva, and chalara ash dieback by fungal spores
  • Waterborne: Spreading through contaminated water such as cholera
  • Oral route: Eating food contaminated with a pathogen
  • Vectors: Animals that spread pathogens in their bites, such as malaria that is spread by mosquitoes
  • Bodily fluids: Spreading through contact with infected body fluids such as blood or semen, for example, HIV
• Chemical defences


  • Lysozyme: Enzyme found in mucus, tears and sweat that kills some bacteria
  • Hydrochloric acid: Found in the stomach, kills most bacteria on food
• Physical barriers


  • Mucus: Sticky substance in most body openings that traps pathogens
  • Ciliated cells: Have hairs that sweep mucus up and out of the body
  • Skin as a physical barrier: Blocks pathogens from entering
• STIs


  Sexually transmitted infections. Pathogens spread through sexual activity
• Preventing STIs


  Use barrier contraception (such as condoms) to prevent mixing of fluids (semen, vaginal lubrication, blood)
• Screening for STIs


  Large scale testing of people to check if they have an STI so they can be treated. This helps to reduce the spread of STIs
• Immune system


  Destroys pathogens that manage to infect us
• Primary immune response


  How the body responds the first time it meets a new pathogen
• Antigens


  Chemical markers on the surface of pathogens (and other cells) that identify them as a pathogen. Antigens are unique to each pathogen

  
• Lymphocyte


  White blood cells that produce antibodies. Each lymphocyte makes a different antibody

  
• Antibodies


  Chemicals with a specific shape that can stick to the antigens on a pathogen and kill it