Bioenergetics

• Photosynthesis


  carbon dioxide + water - glucose + oxygen
• Plants use glucose for:

  Respiration

  Making cellulose

  Making amino acids

  Stored as fats and oils

  Stored as starch
• Limiting factors of photosynthesis

  Light intensity

  Concentration of carbon dioxide

  Temperature

  Chlorophyll
• The Rate of Photosynthesis RP

  1. Place a source of white light at a specific distance from the pondweed
  2. Leave it to photosynthesise for a set amount of time. As it photosynthesises, oxygen will collect in the capillary tube
  3. At the end of the experiment, use the syringe to draw the gas bubble in the tube alongside a ruler to measure the volume of oxygen
  4. Repeat the experiment at the same distance at calculate a mean
  5. Repeat the whole experiment at different distances from the pondweed
• Artificial greenhouse elements for farming


  Using a heater to keep the temperature at the ideal level

  Using shade/ventilation to cool the greenhouse down

  Artificial light to give the plants more quality photosynthesis time

  Paraffin heater to increase the level of carbon dioxide
• Respiration


  The process of transferring energy from glucose which goes on in every cell
• How organisms use energy transferred by respiration


  Build up larger molecules from smaller ones

  Allowing muscles to contract

  Keeping body temperature steady
• Metabolism 


  All the chemical reactions in an organism
• In some, larger molecules are made from smaller ones:

  Lots of small glucose molecules are joined together to form starch

  Lipids are formed from one molecule of glycerol and three molecules of fatty acids

  Glucose is combined with nitrate ions to make amino acids which is them made into proteins
• In others, larger molecules are broken down into smaller ones 


  Glucose is broken down in respiration

  Excess protein is broken down in a reaction to produce urea
• Aerobic respiration


  glucose + oxygen - carbon dioxide + water
• Anaerobic respiration


  glucose - lactic acid
• Anaerobic respiration


  Respiration without oxygen

  Used in emergencies as is doesn't transfer as much oxygen e.g. whilst exercising
• Anaerobic respiration in plants and yeast

  glucose - ethanol and carbon dioxide
• Anaerobic respiration in plants and yeast 


  Anaerobic respiration in yeast- fermentation

  In bread making, its the carbon dioxide that makes bread rise on the fermentation process

  In beer and wine making, its the fermentation process that produces alcohol
• Exercise


  To get more oxygen to the body:

  1. your breathing rate increases
  2. your breath volume increases
  3. your heart rate increases
• Long periods of exercise

  Leads to muscle fatigue- the get tired and don't contract as efficiently
• Oxygen debt 


  The amount of extra oxygen your body needs to react with the build up of lactic acid and remove it.

  This is why the pulse and breathing rate stays high when you stop exercising to get more oxygen into the blood
• Coping with high lactic acid levels 


  Blood transports the lactic acid to the liver where it is converted back into glucose
• Effect of exercise on the body

  1. Take your pulse after: sitting for 5 minutes, 5 minutes of gentle walking, 5 minutes of slow jogging, 5 minutes of running
  2. Your pulse will increase the more intense the exercise is
  3. To reduce random error, do it as a group and plot the average pulse rate for each exercise