B1.3 Respiration

• aerobic respiration is the process of glucose being broken down into carbon dioxide and water
• the word equation for aerobic respiration is glucose + oxygen --> carbon dioxide + water
• anaerobic respiration is the breakdown of glucose in the absence of oxygen
• the word equation for anaerobic respiration is Glucose --> Lactic acid
• Benedict's reagent is a reagent used to test for reducing sugars that produces a different colour based on the amount of sugar present
• bieuret reagent is a reagent used to test for the presence of peptide bonds. a colour change from blue to violet indicates the precense of peptide bonds.
• a carbohydrate is a large molecule that is synthesised from simple sugars
• cellular respiration is the process of breaking down glucose to release energy
• exothermic reaction is when a reacgion releases energy, usually in the form of light or heat
• a fatty acid is a carboxylic acid that has a long carbon chain. fatty acids react with glycerol to make lipids
• idoine solution is a solution used to test for the presence of starch. a colour change from brown to blue-black indicates a positive result.
• lipase is the enzyme that breaks down lipids into fatty acids and glycerol
• a lipid is a large molecule that is synthesised from three fatty acids and a molecule of glycerol
• a non-reducing sugar is a sugar that doesnt have a reducing species (an aldehyde functional group)
• a protein is a large molecule made up of chains of amino acids (monomers)
• respiration occurs inside cells, mainly in mitochondria
• a reducing sugar is a sugar that has a reducing end (aldehyde functional group) present. it acts as a reducing agent and is oxidised itself
• respiration is a chemical process that occurs in the mitochondria of every cell of a living organism to release energy (ATP) for living processes
• living organisms need energy for

  1. muscle contraction
  2. growth
  3. maintaining body temperature
• respiration releases energy stored within the bonds of substrase molecules such as glucose, this energy is then stored as another energy store called ATP (adenosine triphosphate)
• ATP can be 'spent' in order to make chemical reactions occur. the more energy required for a reaction, the more ATP is spent.
• state the name and type of protein molecule linked with respiration

  ATP synthase
• the symbol equation for aerobic respiration is C6H12O6 + 6O2 --> H2O + 6CO2 + 6H2O
• during aerobic respiration, 38 ATP molecules are made, 2 of which are made outside the mitochondria
• 0.04% of air is CO2, 4% of air breathed out is CO2
• oxygen debt is when you have insufficient oxygen and the lactic acid hardens in anaerobic respiration. when you gain oxygen again then it softens again
• in plants and micro-organisms the word equation is glucose --> ethanol + carbon dioxide
• in anaerobic respiration, only 2 ATP molecules are made
• limewater becomes cloudy when carbon dioxide is added to it
• respiritory substances are the nutrients oxidised at the time of celllar respiration to obtain energy
• what nutrients are good sources of energy?

  • carbohydrates (4kcal/g)
  • proteins (4kcal/g)
  • fats (9kcal/g)
• animals store glucose as glycogen and they store it in their muscles
• plants store glucose as starch in their roots and leaves.
• protease enzymes break down protein molecules into amino acids
• suggest why lipids are not polymers

  they are made of 2 different substances, nit just one type of molecule
• what are the roles of lipids?

  insulation, to make cell membranes and energy
• lipase is the enzyme that breaks down lipids (fats)
• carbohydrase enzymes break down carbohydrate polymers. One example is amylase which breaks down starch
• polymers are molecules made of lots of small units called monomers
• lipids provide a chemical energy store. Some animals use them for insulation and buoyancy