organisation

• tissue

  a group of similar cells that performs the same function
• organ


  different tissues working together to perform a function
• organ systems

  a group of organs that work together in performing vital body functions
• catalyst

  a substance, which increases the speed of a reaction without being changed or used up in the reaction
• lock and key model


  the model of the enzyme that shows the substrate fitting perfectly into the active site
• enzymes need

  optimum temperate and pH, ot they denature
• carbohydrates

  starch -> amylase -> maltose
• amylase location

  salivary glands, pancreas, small intestine
• protease 


  protein -> protease -> amino acid
• protease location

  stomach, pancreas, small intestine
• lipase 


  lipid -> lipasse -> glycerol and fatty acid
• lipase location

  pancreas and small intestine
• bile

  a substance produced in the liver that breaks up fat particles and neutralises stomach acid. enzymes work best in alkaline conditions
• liver produces

  bile
• gall bladder stores

  bile
• large intestine absorbs

  excess water
• stomach produces

  hydrochloric acid which kills bacteria
• benadicts test

  • test for carbohydrate
  • water baths set to 75
  • blue to green, yellow or brick red
• biurets tests for

  • proteins
  • blue to pink or purple
• iodine

  • tests for starch
  • orangey brown to blue black
• sudan III

  • test for lipids
  • separate into two layers, the top one being red
• lungs - alveoli

  • air sacks for gas exchange
  • large surface area
  • large blood supply
  • high to low concentration
• heart

  • double secretary system
  • contracts to pump blood around the body
  • has a pacemaker, which is a group of cells in the right atrium
• red blood cells

  • biconcave disc
  • large surface area
  • no nucleus
  • contains haemogoblin
• white blood cells

  • change shape
  • phagocytes or produce anitbodies
  • have a nucleus
• platelet

  small cell fragments that clot the blood, a lack of them can lead to excessive bleeding or brusing
• plasma

  yellow coloured liquids, that carries everything away
• arteries

  carry blood away from the heard under high pressure
• veins 


  blood vessels that carry blood back to the heart under low pressure
• capillaries

  connect veins to arteries they are one cell thick and have permeable walls
• stents

  keep coronary arteries open and supply the heart with blood. the arteries get blocked by fatty deposits which could lead to heart attack.
• satins

  reduce cholesterol in the blood reducing the formation of fatty deposits
• satins advantages

  • reduce risk of heart attack
  • increase good cholesterol
  • prevent other diseases
• satins disadvantages

  • have to be taken regularly
  • negative side-effects
  • time to kick in
• artificial heart

  a pump designed to fit into the human chest cavity and perform the hearts function pumping blood around the body
• artificial heart advantages

  less likely to be rejected
• artifical heart disadvantages

  • not as effective as regular hearts
  • requires major surgery
  • can wear out
  • patient has to take drugs to thin blood
• heart valves

  can be replaced with human mammal or mechanical valves and its less drastic procedure than a heart transplant
• artificial blood

  salt solution, which can replace the blood it gives the patient enough time to produce more blood cells
• health

  a state of complete physical, mental and social well-being and not merely the absence of disease infirmity