The Calvin Cycle: Light Independent Reactions Takes place in stroma of chloroplast Fixes carbon from CO2 into an organic molecule (sugar) Energy stored in sugar comes from ATP and NADPH made in light dependent reactions

Overview of Calvin Cycle Calvin Cycle Animation Calvin Cycle Movie

Events of Calvin Cycle CO2 combines with RuBP (5 C) The resulting 6C molecule splits into two 3C molecules Energy from ATP and NADPH convert the 3C molecules into PGAL (high energy) Of twelve PGAL molecules (produced by two Calvin cycles): Ten regenerate RuBP Two leave the chloroplast and can form glucose

Summary Light Reactions Calvin Cycle Location Inputs Products

Factors that Affect Rate of Photosynthesis Temperature Enzymes control reactions Light intensity Higher intensity = higher energy Availability of water Raw material for photosynthesis Protects plant tissues from damage

C4 and CAM Adaptations for bright, hot conditions Minimize water loss Works in low CO2 levels Requires extra energy CAM Admit CO2 only at night Organic acids formed that release CO2 during the day