C485 Review Sheet for Exam I (Fall ’15)
This sheet is intended as a study aid, not a comprehensive list of everything
we covered. This sheet hits the highlights.
Basic Units Covered:
Light Reactions of Photosynthesis (Ch 19)
Calvin Cycle and Pentose Phosphate Pathway (Ch 20)
The exam will be mostly similar or identical to questions from the review questions, the
questions assigned from the student companion and practice exams. As a rule, you
should know the names and structures of the intermediates in pathways and the roles of
the specific proteins and cofactors associated with those pathways. You should also
know the roles of regulatory molecules associated with pathways and the logic behind the
regulation (i.e. why are NADPH and thioredoxin logical regulators of the Calvin cycle?).
If I gave you a mechanism in class, you are responsible for knowing it. If I did not cover
a mechanism, you don’t have to know it, but you still have to know the transformation.
1) Components of plant photosynthetic systems. Basic structure of chlorophyll and
pheophytin. Organization and function of photosynthetic machinery (figures 19.12,
19.14, 19.17, 19.18, 19.20, 19.25- just the photosynthetic part- 19.26). Stoichiometry of
proton pumping, ATP and NADPH production. Mechanism of plastoquinone reduction
and relevance to proton pumping. Basic structure of water-oxidizing system. Cyclic vs.
noncyclic photophosphorylation. Antenna structure and resonance energy transfer.
2)Stages of the Calvin cycle, chemical intermediates and relevant enzymes. Mechanism
of Rubisco. Role of Mg and active site carbamate. Organization of substrate binding to
Mg. Oxygenase reaction and photorespiration. Fate of products. Stoichiometry of the
Calvin cycle. Mechanism of aldolase. Storage forms of sugars in plants. Activation of
rubisco, regulation of Calvin cycle by thioredoxin (fig 20.16) and NADPH and
environmental factors. Directionality of the pathway and energetically demanding steps.
Stages of the pentose phosphate pathway (PPP), chemical intermediates and relevant
enzymes. Role of the PPP (note figure 20.24) and stoichiometry. Mechanisms of
transaldolase and transketolase. Differences between the calvin cycle and PPP. Structure
and function of thiamine pyrophosphate. Role of glucose 6-phosphate dehydrogenase,
consequences of its deficiency, structure and role of glutathione, particularly in
erythrocytes. Adaptability of the PPP to different biological needs.
3) Basic redox transformations. (As per review problems.) Roles of NADH and FADH2.
Basic strategies for coupling oxidation and other energy-yielding processes to downhill
transformations in pathways.