chloroplasts

• chloroplast envelope

  • double membrane encloses chloroplast
• stroma

  • gel like fluid containing enzymes which catalyse the reactions of photosynthesis
• thylakoid membrane

  • space between double membrane which conditions differ from the stroma= proton gradient
• thylakoids

  • flattened fluid filled sacs
• grana

  • thylakoids stack up to form grana
  • grana are connected by lamaella(continuous membrane)
  • have a large surface area
• photosystems-found in thylakoid membrane

  • 2 types containing different combinations of photosynthetic pigments- chlorophyll A or B
  • each photosystem absorbs different wavelengths of light- allowing maximum light absorption
•  

  Explain the relationship between the structure and functions of a granum in photosynthesis (3) 

  -       Granum is formed from many layers of thylakoid membranes to increase surface area for absorbing light 

  -       As the thylakoid membranes contain chlorophyll to absorb light- for light dependant reaction 

  -       Electron carrier molecules in thylakoid membrane involved in ATP production