Biochem basics

• Mole

  amount of substance in a unit
• Avogadro constant

  the amount of atoms one mole has, 6x10^23
• What is the RAM of one mole of an element equal to? (+ example)

  It's mass in grams e.g. carbon mass of 12g = carbon RAM
• Molar solution

  solution that contains one mole of solute in a litre of solution
• Condensation reaction

  a reaction that joins two molecules together to form a polymer, a water molecule and a chemical bond
• Hydrolysis reaction

  a reaction that breaks the chemical bonds in polymers through the use of a water molecule
• A polymer is a molecule made from a large number of monomers joined together. A macromolecule is a polymer.
• Three examples of monomers are monosaccharides, amino acids and nucleotides.
• Polar molecule

  A charged molecule with uneven charges on either ends. One side is slightly negatively charged, whilst the other is slightly positively charged. An example is water.
• How do we label polar molecules?

  Delta positive and delta negative

  
• What bond does water use?

  Hydrogen bonds (the oxygen is negatively charged whilst the hydrogen is positively charged so they attract each other and join up)
• How do we draw hydrogen bonds?

  Dotted

  
• The negatively charged region of one polarised molecule is attracted to the positively charged region of another polarised molecule. This forms a weak electrostatic bond. This bond can collect together with other electrostatic bonds to form forces that can alter the physical properties of molecules e.g. water.
• The variety of life on earth is due to living organisms being carbon based (essentially: everything comes from carbon)
• Organic molecules

  Contains carbon
• How many atoms can carbon form covalent bonds with?

  4 (other) atoms.
• Serial dilution

  Step-by-step dilution of a substance in solution. The concentration decreases by the same amount in each solution
• The four steps in serial dilution:

  1. Start with a solution of known concentration
  2. Fill a certain number of test tubes with distilled water of the same volume in each test tube
  3. Transfer, with a pipette, the same volume of solution from one test tube to the next. Repeat in each test tube, using the previous test tube to transfer the same volume of solution into the next test tube.
  4. Mix each diluted solution