Everything

• Molecules in living organisms

  • Carbohydrates
  • Proteins
  • Lipids
• These molecules all contain carbon and are described as organic molecules
• Carbohydrates


  Long chains of simple sugars
• Glucose

  A simple sugar (a monosaccharide)
• Maltose


  Formed when 2 glucose molecules join together (a disaccharide)
• Starch, glycogen, cellulose

  Formed when lots of glucose molecules join together (polysaccharides)
• Fats (lipids)


  Most are made up of triglycerides, with 1 glycerol molecule chemically bonded to 3 fatty acid chains

  
• Lipids


  Divided into fats (solids at room temperature) and oils (liquids at room temperature)
• Proteins


  Long chains of amino acids, with about 20 different amino acids

  
• Amino acids join together to form proteins


  Amino acids can be arranged in any order, resulting in hundreds of thousands of different proteins

  
• General amino acid structure


  Contains the same basic structure but the 'R' group is different for each one

  
• DNA


  • The molecule that contains the instructions for the growth and development of all organisms
  • Consists of two strands of DNA wound around each other in a double helix
• Nucleotides


  The individual units of DNA
• Nucleotide


  Contains a phosphate, deoxyribose sugar, and one of four different bases: Adenine (A), Cytosine (C), Thymine (T), or Guanine (G)

  
• DNA base pairing


  • Adenine always pairs with Thymine (A-T)
  • Cytosine always pairs with Guanine (C-G)

  
• The phosphate and sugar section of the nucleotides form the 'backbone' of the DNA strand, and the base pairs of each strand connect to form the rungs of the ladder
• The DNA helix is made from two strands of DNA held together by hydrogen bonds
• Microorganisms can be used by humans to produce foods and other useful substances
• Bacteria


  The most common type of microorganisms used in biotechnology
• Bacteria


  • They are capable of producing complex molecules
  • They reproduce rapidly, meaning the amount of chemicals they can produce can also rapidly increase
• Bacteria

  • There are few ethical considerations to growing them in large numbers in the laboratory
  • They possess plasmids
• Plasmids


  Small, circular loops of DNA which can be an ideal way of transferring DNA from one cell to another during genetic manipulation
• The sequence of bases holds the code for the formation of proteins

  
• Biofuel production

  1. Yeast respires anaerobically, producing ethanol and carbon dioxide

  2. The alcohol produced by fermentation of glucose can be used as biofuel

  
• Biofuel

  • In countries such as Brazil, biofuel is partly replacing petrol as the fuel for cars and other vehicles
• Bread making


  1. Yeast respires anaerobically, producing carbon dioxide

  2. The carbon dioxide produced by fermentation (anaerobic respiration) of glucose is what makes bread dough rise

  
• Fruit juice production

  1. Chopping the fruit up before squeezing helps to release more juice

  2. Adding the enzyme pectinase breaks down pectin, allowing more juice to be squeezed out

  3. Pectinase also helps produce a clearer juice
• Biological washing powders

  • They contain enzymes that quickly break down large, insoluble molecules such as fats and proteins into smaller, soluble ones
  • They are effective at lower temperatures, meaning less energy has to be used
  • They can be used to clean delicate fabrics
• Lactose intolerance

  Inability to produce the enzyme lactase, which breaks down lactose in milk
• Making lactose-free milk

  Adding the enzyme lactase to milk and leaving it to stand to break down the lactose
• Penicillin production

  1. The Penicillium mould produces a chemical that inhibits bacterial growth

  2. The chemical was isolated and named penicillin

  3. Methods have been developed to produce it on a large scale using an industrial fermenter
• Industrial fermenter

  • Conditions can be carefully controlled to produce large quantities of exactly the right type of microorganism
  • Aseptic precautions
  • Optimum temperature
  • Optimum pH
  • Oxygenation
  • Agitation
  • Waste removal
• Mycoprotein production


  1. The fungus Fusarium is cultured in fermenters, providing it with glucose and oxygen

  2. The fungal biomass is then harvested and purified to produce mycoprotein
• Genetic modification

  Changing the genetic material of an organism by removing, changing or inserting individual genes from another organism
• Genetically modified organisms

  • Bacteria producing human insulin
  • Crop plants resistant to insects or herbicides
  • Crop plants producing additional vitamins
• Genetic modification using bacterial production of a human protein

  1. Isolate the required gene using restriction enzymes

  2. Cut a bacterial plasmid with the same restriction enzyme

  3. Join the gene and plasmid using DNA ligase

  4. Insert the genetically engineered plasmid into a bacterial cell
• Bacteria for genetic engineering

  • They contain the same genetic code as the organisms we are taking the genes from
  • There are no ethical concerns over their manipulation and growth
  • The presence of plasmids makes them easy to remove and manipulate
• Animal cells


  • Multicellular
  • Contain a nucleus with a distinct membrane
  • Do not have cellulose cell walls
  • Do not contain chloroplasts (so they are unable to carry out photosynthesis)
  • Feed on organic substances made by other living things
  • Often store carbohydrates as glycogen
  • Usually have nervous coordination
  • Able to move from place to place
• Plant cells


  • Multicellular
  • Contain a nucleus with a distinct membrane
  • Have cell walls made out of cellulose
  • Contain chloroplasts (so they can carry out photosynthesis)
  • Feed by photosynthesis
  • Store carbohydrates as starch or sucrose
  • Do not have nervous coordination
• Cell Structures Found in Both Animal and Plant Cells


  • Nucleus
  • Cell membrane
  • Cytoplasm
  • Mitochondria
  • Ribosomes
  • Vesicles