In article <199611011420.IAA21137 at mari.acc.stolaf.edu>,
ceumb at STOLAF.EDU wrote:
>Dear Plant Edders,
>>A friend asked me a question the other day about chlorophyll. He was
>wondering why blue and red but not green were absorbed. After some
>reading and chatting with colleagues I came to the short answer that
>chlorphyll was so efficient with red and blue that there was no
>evolutionary advantage in absorbing green and/or that changes needed
>to absorb green would mean loss of efficiency absorbing blue or red.
>
This is not really accurate. Chlorophyll DOES absorb green light, but less
efficiently than red and blue light. Shine white light through a single leaf
and you will see some of the green light coming through. Shine light through a
thickness of several leaves and virtually no green light will get through.
In practice, a crop canopy, or several metres depth of algal culture will
absorb a great deal of green light and use it for photosynthesis.
Jonathan B. Marder , Department of Agricultural Botany
E-mail: MARDER at agri.huji.ac.il | The Hebrew University of Jerusalem
Phone: (08 or +9728) 9481918 | /\/ Faculty of Agriculture
Fax: (08 or +9728) 9467763 |/ \ P.O.Box 12, Rehovot 76100, ISRAEL
http://www.agri.huji.ac.il/~marder
