organisation

• gas exchange system includes...


  trachea, intercoastal muscles, bronchi, bronchioles, alveoli, diaphragm
• alveoli are adapted by having...

  large surface area (diffusion), good blood supply(maintain conc. gradient), walls thin(short diffusion pathway)
• red blood cells adapted by...

  biconcave shape(large surface area), no nucleus(more room to carry O2)
• positives and negatives of having a stent:


  lowers risk of heart attack, fast recovery time; risk of heart attack after surgery, infection after surgery, blood clotting
• positives and negatives of statins:

  reduce risk of strokes, coronary heart disease and heart attacks; increase good cholesterol; taken continuously, side effects, no immediate effect
• cardiovascular disease caused by...

  diet with lots of LDL(bad) cholesterol(blocks arteries and inc. blood pressure); smoking (damages arteries)
• cardiovascular disease reduced by...

  exercise and reduce strain on heart
• cancer caused by...


  carcinogens
• pregnancy risked by...


  smoking and alcohol
• lung diseases caused by...

  smoking thinning lung lining
• liver and brain function risked by...

  alcohol
• type 2 diabetes risked by...

  obesity
• lifestyle risk factors for cancer:


  smoking, obesity, uv light, viral infections
• epidermal tissue has...


  waxy cuticle
• palisade mesophyll has...


  lots of chloroplasts
• spongy mesophyll tissue has...

  lots of air spaces
• what do guard cells do?

  open and close stomata
• what are guard cells sensitive to?

  light
• where are more stomata found?

  bottom of leaf
• why are there stomata on the bottom of the leaf?

  minimise water loss by evaporation(shaded and cooler)
• starch test


  iodine brown to blue black
• sugar test


  benedicts in hot water blue to BRICK red
• protein


  biuret shaken blue to purple
• lipids


  ethanol with equal amount of distilled water forms white emulsion
• how to prepare sample for food test:


  grind with pestle and mortar; mix with water; filter with filter paper and funnel
• all tests put into a...

  test tube
• all tests add...


  few drops of chemicals except for sugar test
• all tests have...


  colour change except for lipids
• lipids 2nd test


  sudan iii forms red layer on top
• amylase produced in


  salivary glands and pancreas
• amylase breaks down


  carbs into simple sugars
• aorta takes


  oxygenated blood away from heart to body
• benign


  doesnt spread
• bile made in


  liver
• bile stored in


  gallbladder
• bile...


  neutralises stomach acid and emulsifies fats
• blood contains


  rbc, wbc, platelets and plasma
• capillary


  thin blood vessel for exchange of substances
• coronary heart disease


  build up of fat in artery
• coronary artery effects


  narrows artery and reduces blood flow