Figure 8.1 The light and carbon reactions of photosynthesis in chloroplasts of land plants

Figure 8.2 The Calvin–Benson cycle proceeds in three stages

Figure 8.3 The Calvin–Benson cycle

Calvin cycle can be divided into three phases: ― Carboxylation of the ribulose-1,5-bisphosphate, followed by hydrolysis to generate two molecules 3-phosphoglycerate (3-PGA)

― Reduction of 3-phosphoglycerate to glyceraldehyde-3-phosphate (G-3-P)

― Regeneration of the initial acceptor molecule ribulose-1,5-bisphosphate, thereby creating a continuous cycle

The Glycolate pathway returns reduced carbon from phosphoglycolate to the Calvin cycle

• Glycolate pathway: Break down phosphoglycolate and recover 75% of the reduced carbon present in phosphoglycolate to the Calvin cycle, with the remaining 25% released as CO2.

• Glycolate pathway is characterized by light-dependent CO2 release and is also called photorespiration

Figure 8.3 The Calvin–Benson cycle; The carboxylation and reduction phases (Part 1)

Figure 8.3 The Calvin–Benson cycle; The regeneration phase (Part 2)

Figure 8.4 Carboxylation and oxygenation of ribulose 1,5-bisphosphate catalyzed by rubisco

Figure 8.5 CO2 functions both as activator and as substrate in the reaction catalyzed by rubisco

Figure 8.6 The ferredoxin–thioredoxin system

Figure 8.7 Regulation of chloroplast phosphoribulokinase and glyceraldehyde-3-P dehydrogenase

Figure 8.8 Operation of the C2 oxidative photosynthetic cycle

Figure 8.11 The C4 photosynthetic carbon cycle involves five successive stages

Figure 8.12 The C4 photosynthetic pathway in leaves

Figure 8.12 C4 photosynthetic pathway; (A) Kranz anatomy, compartmentalization in cell

Figure 8.12 C4 photosynthetic pathway; (B) Kranz anatomy in a C4 dicot

Figure 8.13 Crassulacean acid metabolism (CAM)

Figure 8.14 Carbon mobilization in land plants

Figure 8.18 Interconversion of hexose phosphates