health and disease

• Chemical plant


  Releases compounds that attract larger insects
• Enzymes


  Bind to toxins to neutralise them
• Immunisation


  Vaccine contains dead/inactive form of pathogen, stimulates WBCs to produce antibodies (leads to herd immunity)
• Advantages of immunisation


  • Found in WBCs to kill and digest pathogens
  • Stomach kills bacteria in food before reaching intestines
  • Phagocytes can't make you ill
• Plant diseases


  • Chalara ash dieback causes malformations, leaf browning
  • Tobacco mosaic virus causes leaf discolouration
  • Bacterial canker on fruit causes leaf loss, stunted growth, pus-filled lesions
  • Aphids cause structural damage
• Plant disease diagnosis


  1. Cuttings taken from diseased plant

  2. Virus/bacterium grown on agar plate

  3. Tested using monoclonal antibody testing kit (ELISA kit)
• Mucus

  Produced by goblet cells in airway, traps bacteria before reaching lungs
• Cilia


  Waft away mucus that has trapped pathogens to be killed by stomach acid
• Phagocytes


  Engulf pathogens, identifying plant disease
• Antibodies


  Each pathogen has a specific, complementary antibody
• Advantages of antibodies


  • Eradicated many diseases
  • Prevents epidemics
• Disadvantages of antibiotics


  • Not always effective
  • Can cause bad reactions
• Antibiotics


  Break cell wall, used to treat bacterial infections not those caused by viruses, fungi, other pathogens
• Aseptic technique


  1. Sterilised agar jelly poured into petri dish, left to cool and set

  2. Sterilised wire loops dipped into solution of microorganism, spread over jelly

  3. Incubated (stored upside down)
• Health


  Not merely the absence of disease or infirmity
• Communicable diseases


  Can be transferred between individuals
• Non-communicable diseases


  Cannot be transferred between individuals (usually genetic or due to lifestyle factors)
• Viruses


  Very small, move into cells and use biochemistry to make replicas of themselves
• Lytic pathway of viruses

  Virus replicates DNA, once full, bursts into lysis, repeated
• Lysogenic pathway of viruses

  Virus inserts DNA into host cell
• Communicable diseases


  • HIV
  • Cholera
  • Tuberculosis
  • Chlamydia
  • Ebola
• Bacteria


  • Small
  • Can produce spores which spread
  • Multiply very quickly through binary fission
  • Produce toxins that can damage cells
• Fungi


  • Can produce spores which spread to other organisms
• Physical plant barriers


  • Thick waxy cuticle
  • Thick cellulose wall
  • Bark
  • Leaves close stomata
• Aseptic technique


  1. Petri dishes sterilised by UV light

  2. Inoculating loop sterilised by passing through flame

  3. Lid of petri dish sealed with tape

  4. Incubated at 25 below human optimum
• Monoclonal antibodies


  Antibodies that have been produced from a single activated immune cell, only bind to one antigen
• Uses of monoclonal antibodies

  • Pregnancy tests
  • Analysing blood in labs
  • Treatment of disease (cancer)
• Monoclonal antibody production


  Scientists obtain lymphocytes from mice, produce antibody clones
• Monoclonal antibody testing


  1. 1st section mobile antibodies complementary to hCG (blue beads)

  2. 2nd section stationary antibodies complementary to hCG stuck to stick

  3. hCG binds to mobile antibodies, carried in flow to 2nd section, bind to blue beads, blue + line
• Advantages of monoclonal antibodies

  • Healthy cells not affected
  • Can be engineered to treat lots of conditions
  • Mouse-human hybrid cells reduce chance of triggering immune response
• Disadvantages of monoclonal antibodies

  • Difficult to attach to drugs
  • Expensive to develop
• Factors affecting non-communicable diseases

  • BMI (mass/height^2)
  • Waist-hip ratio
  • High intake of saturated fat
  • Sedentary lifestyle
  • Smoking
  • High alcohol intake
• Treatments for cardiovascular disease

  • Life-long medication to reduce cholesterol/blood pressure
  • Surgical procedures like coronary artery bypass, metal stents
  • Lifestyle changes like reducing saturated fat, regular exercise, reducing salt intake
• Obesity


  Eating more calories than burned from exercise, can lead to type 2 diabetes
• Malnutrition


  Eating fewer calories than burned, body not receiving enough vitamins/minerals
• Photosynthesis


  Process where plants use light energy to convert carbon dioxide and water into glucose and oxygen