Cardiovascular

• Cardiovascular disease


  Diseases of the heart or blood vessels, for example coronary heart disease
• What are Stents

  1. Inserted into arteries

  2. Keep arteries open

  3. Allow blood flow to heart muscle
• What happens when Coronary arteries get blocked

  • Causes narrowing of arteries
  • Restricts blood flow
  • Leads to heart attack
• Risks of Stent surgery

  Risks include complications during operation, infection, blood clots
• Cholesterol


  Essential lipid that the body needs, but too much 'bad' (LDL) cholesterol can cause problems
• Too much 'bad' cholesterol

  • Causes fatty deposits in arteries
  • Leads to coronary heart disease
• Statins


  Drugs that can reduce the amount of 'bad' cholesterol in the bloodstream
• Advantages of statins


  • Reduce risk of strokes, coronary heart disease and heart attacks
  • Increase 'good' (HDL) cholesterol
  • May help treat other diseases
• Disadvantages of statins


  • Long-term drug that must be taken regularly
  • Can cause negative side effects like headaches, kidney failure, liver damage, memory loss
  • Effect isn't instant
• Investigating enzymatic reactions


  1. Add amylase and buffer solution to boiling tube

  2. Add starch solution

  3. Time how long it takes for amylase to break down starch

  4. Repeat with different pH buffer solutions
• Rate of reaction


  Measure of how much something changes over time
• Calculating rate of reaction


  • Rate = 1000 / time (in seconds)
  • Example: 24 cm³ of oxygen released in 50 seconds, rate = 24 cm³ / 50 s = 0.48 cm³/s
• Viral diseases


  • Measles
  • HIV/AIDS
• Measles


  • Spread by droplets
  • Causes skin rash and fever
  • Can lead to serious complications
  • Preventable by vaccination
• HIV/AIDS


  • Initial infection has no symptoms for years
  • Attacks immune cells
  • Late stage infection leads to inability to fight other infections
• Tobacco mosaic virus


  • Affects many plant species
  • Causes mosaic pattern on leaves
  • Reduces photosynthesis
• Rose black spot


  • Fungus that causes purple/black spots on rose leaves
  • Leaves turn yellow and drop off
  • Reduces plant growth
  • Spreads through water and wind
  • Can be treated with fungicides and removing affected leaves
• Malaria


  • Caused by a protist
  • Part of life cycle in mosquitoes
  • Causes recurring fever episodes
  • Can be fatal
  • Spread can be reduced by stopping mosquito breeding and using insecticides/nets
• Bacterial diseases


  • Food poisoning
  • Gonorrhoea
• Food poisoning


  • Caused by toxins produced by bacteria
  • Can be caused by eating contaminated food
• Gonorrhoea


  • Sexually transmitted disease
  • Caused by bacteria
  • Symptoms include pain when urinating and discharge
  • Originally treated with penicillin but now resistant strains exist
  • Can be prevented by using barrier contraception
• Ways to reduce/prevent disease spread

  • Good hygiene practices
  • Destroying disease vectors
• Gonorrhoea


  Causes pain when urinating, thick yellow or green discharge from the vagina or penis
• Gonorrhoea treatment


  Originally treated with penicillin, but bacteria have become resistant
• Preventing gonorrhoea spread


  Treat with antibiotics, use barrier contraception like condoms
• Ways to reduce or prevent disease spread

  • Being hygienic - washing hands
  • Destroying disease vectors like insects
  • Isolating infected individuals
  • Vaccination
• Plants can get diseases caused by viruses, bacteria and fungi
• Signs of plant disease

  • Stunted growth
  • Spots on leaves
  • Patches of decay
  • Abnormal growths
  • Malformed stems/leaves
  • Discolouration
• Identifying plant diseases


  Look up signs in gardening manual, take to lab for pathogen identification, use testing kits
• Plant physical defences


  • Waxy cuticle
  • Cell walls
  • Layers of dead cells
• Plant chemical defences


  • Antibacterial chemicals
  • Poisons to deter herbivores
• Plant mechanical defences


  • Thorns and hairs
  • Leaves that droop or curl
  • Mimicry of other organisms
• Photosynthesis


  Process that uses light energy to convert carbon dioxide and water into glucose and oxygen
• Photosynthesis is endothermic - energy is transferred from the surroundings
• Photosynthesis takes place in chloroplasts in plant cells
• Ways plants use glucose

  • Respiration
  • Making cellulose
  • Making amino acids
  • Storing as oils/fats
  • Storing as starch
• Limiting factors of photosynthesis

  Light intensity, CO2 concentration, temperature
• Chlorophyll can also be a limiting factor of photosynthesis
• Aerobic respiration


  Fast process that transfers energy from glucose using oxygen
• Anaerobic respiration


  Incomplete breakdown of glucose without oxygen, producing lactic acid