the interrelationship between photosynthesis + relationship

• compensation point - where photosynthesis + respiration proceed at same rate, so that there is no net gain or loss of carbohydrate 
• Importance of photosynthesis

  • used by plants, algae + some types of bacteria to convert light energy from sunlight into chemical energy

  autotrophic nutrition when organisms use this chemical energy To synthesise large organic molecules

  • Photosynthesis-using organisms are photoautotrophs as they use light energy source for autotrophic nutrition

  -> also described as 'producers’ as they’re first trophic level (beginning of food chain) → provide energy + organic molecules to other, non-photosynthetic organisms

  6CO2 + 6H2O + Energy →(chlorophyll →C6H12O6 + 6O2
• Photon

  particle of light contain an amount (quantum) of energy

  photosynthesis is an example of carbon fixation, when CO2 is converted into sugars

  → carbon is for synthesising all types of organic molecules (carbon fixation)

  • carbon fixation is endothermic, needing energy

  → also needs electrons; reduction reaction

  • carbon fixation helps regulate concentration of carbon dioxide in atmosphere + oceans
  • most forms rely directly or indirectly on photosynthesis
• Respiration

  organisms that photosynthesise also respire

  • in respiration, they oxidise organic molecules that they’ve previously synthesised by photosynthesis + stored, releasing chemical energy
  • non-photosynthetic organisms are heterotrophs -> obtain energy by digesting complex organic molecules of food to smaller molecules that they can use as respiratory substrates [so obtain energy from products of digestion by respiration] exothermic → releases energy C6H12O6 + 6O2 → 6H2O + 6CO2 + energy
• How they both interrelate

  • both important in cycling CO2 + O2 in atmosphere → products of one process are raw materials for the other process: aerobic respiration removed oxygen + adds carbon dioxide vice versa
  • - compensation point
  • - compensation period