Photosynthesis

• photosynthesis


  the process by which plants use sunlight to make their own organic compounds (food)
• the photosynthesis reaction

  carbon dioxide + water = glucose + oxygen
• photosynthesis occurs in the chloroplast
• light dependent stage:

  -uses the sun

  -occurs in the thylakoids

  -chlorophyll in the thylakoids captures light energy, the light energy then breaks down water into oxygen and hydrogen
• light independent stage:

  -doesn't need the sun

  -occurs in the stroma (where the hydrogen is now)

  -atp energy is used to combine CO2 and hydrogen, then glucose is produced
• more light=faster rate of photosynthesis (until it reaches the optimal rate, then the graph plateaus)
• more CO2= faster rate of photosynthesis (eventually, the chloroplasts are running at full capacity so the graph plateaus because then the CO2 has no effect)
• temp rising=faster rate of photosynthesis (temp affects the enzymes which catalyse photosynthesis)
• as super high temperatures enzymes denature, lowering the rate of photosynthesis
• ultimately, a combination of factors (light intensity+CO2 levels+temperature) affect the rate of photosynthesis
• The relationship between photosynthesis and respiration:

  • photosynthesis- CO2 + water + light=glucose + oxygen
  • respiration- glucose + oxygen + (release of ATP)=CO2 + water