BIOL 4160 Midterm: BIOL 4160 Exams_2008
Document Summary
Photosynthesis (sc/biol 4061) first term test (8 oct 2008) Answer four of the following five questions in the exam booklet provided. When finished, please insert the question sheet and your crib sheet(s) in the exam booklet (all will be returned to you after grading). There are three types of evidence for primordial" photosynthesis. Some are consistent with the presence of photosynthesis (either anoxygenic or oxygenic). Describe the three lines of evidence and why they support the primordial" presence of either anoxygenic and/or oxygenic photosynthesis. Describe two distinct examples of proteobacterial photosynthesizers that exhibit unusual pathways of carbon dioxide fixation, emphasizing their unique photosynthetic properties compared to oxygenic photosynthesizers, such as cyanobacteria, algae and higher plants. A typical e donor in proteobacterial groups is h2s. Predict the s h bond energy, compared to the o h bond energy of h2o (460 kjoules mol 1). The chemical structure is cyanidin, an example of an anthocyanin.
