Regarding teaching cyclic and non-cycling electron flow in the light reactions:
In our intro biology course, I do not say anything about cyclic flow. As a
student, I couldn't figure out why we were learning it, and as a teacher all
I could figure was that cyclic was presented first as a pedagogical ploy
(start simple, then move to more complex). Most of the texts don't even
mention cyclic is an evolutionary precursor to non-cyclic. My personal view
is that it is far less confusing to teach just the non-cyclic. They can
learn about cyclic in plant physiology or in a course which addresses the
evolution of biochemical pathways.
Kathleen Archer
Dept. Biology
Trinity College
Hartford, CT 06106
e-mail: kathleen.archer at mail.trincoll.edu
Ph: (203) 297-2226
