Why plants leaves are green?

Why plants leaves are green?

PROF WAQAR HUSSAIN

        

          The colour of plant leaves is green due to the presence of chlorophyll in their chroloplasts. Chlorophyll is responsible for the photosynthesis and helps plant to utilize water of the ground, the carbon dioxide of atmosphere and the sunlight of the space to bind H₂O and CO₂ molecules to synthesis glucose and oxygen.So chlorophyll is the factory of plant which provides food for plants and oxygen for the animals.

      Chloro means green. It is an organo-mentallic complex of porphyrins esterified with long chain alcohol of phytol. Magnesium atom is present in the centre of chlorophyll. It effectively absorb blue and red light.
    The chlorophyll is green because it absorbs red and blue colour wavelengths and green is not absorbed thus it is reflected back and reach the eyes and plant looks green.

          

         With the approach of autumn, plants produce less chlorophyll because light regulates the production of chlorophyll.As a result, the green colour fade. The other pigment that affect the leaf colour are anthocyanin which makes the leaf red; caroteniods stain the leaf red, yellow or orange.