Photosynthesis

• Enzymes are biological catalysts (speed up reactions)
• Light energy


  Energy from the sun that is used in photosynthesis
• Carbon dioxide


  Gas from the air that is used in photosynthesis
• Chloroplasts


  Organelles found in green leaf cells that contain chlorophyll
• Chlorophyll


  Green pigment that traps light energy
• Photosynthesis

  1. Light energy is trapped by the green pigment chlorophyll

  2. Carbon dioxide from the air is absorbed

  3. Water from the soil is absorbed

  4. Glucose is stored as starch
• Glucose


  A type of sugar that is a product of photosynthesis
• Photosynthesis is a series of enzyme-controlled reactions that allows green plants to make glucose using light energy from the sun
• Water


  Liquid from the soil that is used in photosynthesis
• Enzymes are sensitive to temperature
• Starch


  A polysaccharide that is a product of photosynthesis and is used for energy storage
• Photosynthesis


  Process by which green plants, algae, and some bacteria convert light energy, usually from the sun, into chemical energy in the form of glucose
• Carbon fixation


  Second stage of photosynthesis where carbon dioxide is converted into glucose
• Light reaction


  First stage of photosynthesis where light energy is absorbed and converted into chemical energy
• Raw materials

  • Carbon dioxide
  • Water
• Absorbed by

  • Chlorophyll
• Glucose


  Useful product produced by photosynthesis
• Stage 1: The Light Reaction

  1. Chlorophyll in the leaves traps light energy from the sun

  2. The light energy is converted into chemical energy and used to generate ATP

  3. Water is split to produce hydrogen and oxygen

  4. Oxygen diffuses from the cell and escapes into the atmosphere

  5. Light energy is absorbed by chlorophyll in the leaves as chemical energy
• ATP

  Adenosine triphosphate, a complex organic chemical that provides energy to all the cells in an organism
• End products of water splitting

  • Hydrogen
  • Oxygen
• Chloroplasts


  Organelles in the cells of green plants that convert light energy into chemical energy
• Water is split

  1. Produces hydrogen and oxygen

  2. Oxygen diffuses from the cell and escapes into the atmosphere
• Energy for the reaction comes from ATP produced by the light reaction
• A series of enzyme-controlled reactions in the chloroplast, which use hydrogen (from the light reaction) with carbon dioxide produce sugar (glucose)
• Stage 2: Carbon Fixation


  1. Carbon dioxide and hydrogen undergo a series of enzyme-controlled reactions

  2. Carbon dioxide (from the air)

  3. Hydrogen present in leaves (from stage 1)

  4. AFP (from Stage 10) provides energy for the reaction

  5. 2+

  6. BATTERY

  7. 수
• Glucose produced during photosynthesis in plants

  • Broken down to release chemical energy
  • Converted into starch (for storage)
  • Converted into cellulose (for cell structures)
• Limiting factor


  A factor which if in short supply limits or holds up the process of photosynthesis
• Limiting factors


  • If in short supply limits or holds up the process of photosynthesis
• Enzymes

  Proteins that speed up chemical reactions
• Light


  Radiant energy that can be seen and used by plants for photosynthesis
• Main limiting factors

  • Enzymes
  • Light
  • Carbon dioxide concentration
• Carbon dioxide concentration


  The amount of carbon dioxide available for photosynthesis
• Limiting factor graphs


  • Graphs that show the relationship between the rate of photosynthesis and the limiting factor