Certainly! The **Calvin cycle** is a crucial part of photosynthesis in plants. Let me break it down for you: 1. **Overview**: - The Calvin cycle occurs in the **stroma** of chloroplasts. - It's also known as the **light-independent reactions** because it doesn't directly rely on light. - Carbon dioxide (CO₂) from the air enters the leaf through **stomata** and diffuses into the stroma. - The goal: **synthesize sugar**. 2. **Stages**: - **Carbon Fixation**: - CO₂ combines with a five-carbon molecule called **ribulose-1,5-bisphosphate (RuBP)**. - This forms a six-carbon compound that splits into two molecules of **3-phosphoglyceric acid (3-PGA)**. - Enzyme involved: **rubisco**. - **Reduction**: - ATP and NADPH (from light reactions) help convert 3-PGA into **glyceraldehyde-3-phosphate (G3P)**. - Some G3P molecules are used to make glucose, while others regenerate RuBP. - **Regeneration**: - Remaining G3P molecules regenerate RuBP. - The cycle runs multiple times to produce one glucose molecule. 3. **Importance**: - The Calvin cycle is essential for **carbon fixation** and creating organic matter. - All living organisms depend on it indirectly.