Chloroplasts I

• Chloroplasts

  in eukaryotes (plants)
• structure of chloroplasts

  • double membrane (inner + outer)
  • stroma (fluid)
  • thylakoid (sac-like structures stacked together which have membranes themself)

  
• Light consequences occur in chloroplasts.

  • If light combines with matter there is....
  • transmission of that light (goes through matter)
  • reflection of that light (re-emitted/ giving off light)
  • absorption of that light (photosynthesis!!!)
• Light must be absorbed by

  photosynthetic pigments
• Photosynthetic Pigments

  Def: Substance that absorbs visible light.

  Function: capture/absorb light for photosynthesis

  Location: embedded in the thylakoid membrane
• Chlorophyll

  • main photosynthetic pigment
  • absorbs visible light
• Chlorophyll Structure

  • Chlorophyll has to be embedded in a membrane
  • long hydro-carbon (HC) tail inserted into thylakoid membrane
  • this tail is hydrophobic
  • embedded within TM; anchor
• Chlorophyll structure

  • porphyrin ring
  • this part specifically absorbs light E
  • has C and N
  • Magnesium ion in center
• Chlorophyll a

  • primary photosynthetic pigment (1 with degree sign)
  • has methyl group (CH3)
  • bright green color
• Summary 


  Chloroplasts are an organelle in plant cells with a structure similar to mitochondria (double membrane, stroma and thylakoid*). They have photosynthetic pigments whose main job is to capture and absorb visible light. How? these pigments are embedded in the thylakoid membrane and use chlorophyll, the main photosynthetic pigment.