BIOL1007 Lecture Notes - Lecture 9: Light-Independent Reactions, Chloroplast Dna, Carbon Fixation
Document Summary
Explain fixation of carbon dioxide in the calvin cycle: key advancement in development of calvin cycle was using radiocarbon to trace carbon through the cycle. In plants, carbon dioxide enters the interior of a leaf via pores called stomata and diffuses into the stroma of the chloroplast the site of calvin cycle reactions, where sugar is synthesised. In the calvin cycle, carbon atoms from co2 are fixed (incorporated into organic molecules) and used to build three-carbon sugars process is fuelled by, and dependent on, atp and. Compare carboxylation and oxygenation by rubisco: rubisco is the most abundant protein on earth ribulose bis-phosphate carboxylase/oxygenase, rubisco is found in the chloroplast stroma. 8 large sub-units, gene within chloroplast dna. 8 small sub-units, genes within nucleus dna. Ribulose 1,5-biphosphate reacts with oxygen, it gives a molecule of glycerate phosphate and another of glycollate-2-phosphate. Rubisco: wollemi grows 80% faster at 1200ppm co2 than at current concentrations, other species only grow 10-30% faster.
