Absorption and Action spectra

• Absorption spectra:

  • graph that shows absorbance of different wavelengths of light by a particular pigment
• Chlorophylls

  • absorb blue-violet and red regions of light spectrum
• Carotenoids

  • absorbs wavelengths of light (mainly in blue-violet region) of spectrum
• Absoprtion spectra graph

  
• Action spectra:

  • graph showing the rate of photosynthesis at different wavelengths of light
  • Rate of photosynthesis is highest at blue-violet and red regions of light spectrum
  • these are the wavelengths of light that plants can absorb (Wavelength of light that chlorophyll and carotenoids can absorb)
• Diagram 2

  
• Strong correlation between the cumulative absorption spectra of all pigments and action spectrum:

  • both graphs have two main peaks (Blue-violet and red)
  • Both have a trough at the green-yellow region of light spectrum
• Diagram C: