Photosynthesis

• WHAT IS PHOTOSYNTHESIS

  The conversion of light energy into chemical energy that is stored in organic compounds
• WHAT IS THE EQUATION FOR PHOTOSYNTHESIS?

  6CO2 + 6H2O + LIGHT ENERGY→ C6H12O6 + 6O2
• Where does photosynthesis occur?


  Chloroplasts of the mesophyll cell
• Structure of the leaf

  
• What is the function of the waxy cuticle?

  Prevents water loss
• What is the function of the upper and lower epidermis?

  Protection (protective layer of cells)
• What is the function of the palisade mesophyll layer?

  Contains chloroplasts therefore it is packed to attract more light
• What is the function of the Spongy mesophyll layer?

  It contains airspaces which aids in the diffusion of gases
• What is the function of the Xylem?

  Provides water
• What is the function of the Phloem?

  Takes products of photosynthesis away
• What makes up the Vascular bundle?

  Xylem and phloem
• What is the function of the Stomata

  Allows CO2 to enter
• What is the function of the Guard cells?

  Regulates gas exchange as it opens and closes the stomata pores
• Define stomata

  The pores in a plants cuticle where water vapor and gases are exchanged between the plant and the atmosphere
• The parts of the chloroplast:

  • Thylakoid
  • grana
  • stroma
  • starch grains
  • intergranal lamella
  • small ribosomes
  • circular DNA
  • DBL membrane
• What are photosynthetic pigments?

  Compounds that absorbs light. Each pigment absorbs different wavelengths of white light
• What are the different pigments?

  Chlorophyll ( A and B) and Carotenoids (Carotene and xantophylls)
• What is chlorophyll?

  The most abundant pigment located in the thylakoid membranes that absorbs red and blue light (photons) causing green to be reflected.
• Chlorophyll A

  Involved in light dependent reactions and they absorb longer wavelengths
• Chlorophyll B


  Assists in capturing light energy
• What are carotenoids

  Accessory pigments that capture a wide range of short wavelengths (red, orange and yellow)
• What is the purpose of carotenoids

  They protect the chlorophyll by absorbing some of this energy and passing it on to the chlorophyll
• The main form of energy from the sun is in the form of electromagnetic radiation
• What are photosystems?

  Photosynthetic pigment molecules or light harvesting clusters that absorb light
• absorption of Photosystem 1

  700nm
• Absorption of photosystem 2

  680nm
• What is the light dependent stage?

  This is the stage where energy from the sun is transferred into the production of ATP and the coenzyme NADP is reduced.
• What is ATP composed of?

  Adenine, ribose and 3 phosphate groups