Bioenergetics

• Photosynthesis word equation


  Carbon dioxide + water -> glucose + oxygen
• Photosynthesis symbol equation


  6CO2 + 6H2O ------> C6H12O6 + 6O2
• Photosynthesis


  -endothermic reaction

  -energy transferred from the environment to the chloroplasts by light
• Plant uses glucose in five main ways

  -respiration

  -insoluble starch for storage

  -produce fat pr oil for storage : storing in seeds

  -cellulose : strengthens the cell wall

  -amino acids: protein synthesis
• Limiting Factos of Photosynthesis:

  - available light

  - temperature

  - amount of water

  - amount of C02

  - amount & physiological state of chloroplast.
• cellular respiration is an...

  Exothermic reaction which is continuously occurring in living cells
• aerobic respiration


  Uses oxygen
• anaerobic respiration


  Does not use oxygen
• ananerobic respiration equation


  Glucose -> lactic acid
• anaerobic respiration leads to ...

  Oxygen debt
• Anaerobic respiration in plants and yeast

  Glucose --> ethanol + carbon dioxide
• Respiration in yeast cells is called

  Fermentation

  -economic importance in the manufactur of bread and alcoholic drinks
• Organisms need energy for:

  Chemical reactions to build larger molecules, movement, keeping warm
• aerobic respiration equation


  glucose + oxygen -> carbon dioxide + water

  C6H1206 + 02 -> CO2 +H20
• During exercise the human body reacts to the increased demands...

  Fro energy
• Heart rate, breathing rate and breath volume increase during...

  Exercise to supply the muscles with more oxygenated blood
• If insufficient oxygen is supplied anaerobic respiration...


  Takes place in the muscles
• Incomplete oxidation of glucose causes a build up of...

  Lactic acid and creates an oxygen debt.
• During long periods of vigorous activity muscles become...

  Fatigued and stop contacting efficiently
• Blood flowing through the muscles transports the lactic acid to the...


  Liver where it is converted back into glucose
• oxygen debt


  is the amount of extra oxygen the body needs after exercise to react with the accumulated lactic acid and remove it from the cells
• Metabolism


  Sum of all the reactions in a cell or the body
• Energy transferred by respiration in cells is used by the organism for the ...


  Continual enzyme controlled processes of metabolism that synthesis new molecules
• Metabolism includes:


  - conversion of glucose to starch, glycogen and cellulose

  - the formation of lipid molecules from a molecule of glycerol and three molecules of fatty acids

  - the use of glucose and nitrate ions to form amino acids which in turn are used to synthesise proteins

  - respiration

  - breakdown of excess proteins to form urea for excretion