Photosynthesis

• Photosynthesis is the way green plants make their own food using chlorophyll(in their chloroplast) & sunlight
• Chlorophyll is a green chemical that uses light energy to make food from CO2 & H2O
• Conditions for Photosynthesis:

  • Light: energy
  • Chlorophyll: carries out the reaction
  • Co2: building block for food(from atmosphere)
  • H2O: building block for food(from soil)
• Word equation:

  Carbon dioxide+Water =(light+chlorophyll) glucose+ oxygen
• Chemical equation

  6CO2+6H2O=(light+chlorophyll) C6H12O6+6O2
• Uses of glucose(food) in plant:

  1. Produce energy for respiration
  2. Convert into protein for growth
  3. Stored as starch
  4. Converted to cellulose for new cell walls
• Factors affecting the rate of photosynthesis:

  • Light: increases/decreases rate
  • CO2: increases/decreases rate
  • Temperature: high+low temps. reduce photosynthesis (enzyme controlled)
• Mineral requirements:

  1. Nitrogen(N) - promotes leaf growth, part of proteins in cells
  2. Potassium(K)- promotes rooth growth, part of cell membranes
  3. Phosphorus(P)- promotes growth in leaves+ fruit, increases the hardiness
• Fertilising soil, using either manure or chemical fertilisers, means that we add extra minerals to the soil