32 public questions tagged with this topic.
ATP provides energy, and NADPH provides reducing power for the conversion of COâ‚‚ into carbohydrates in the Calvin cycle. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Biology Textbook for Class XI and XII (Botany section), Chapter: Biology - Botany portion covering relevant concept.
Chloroplasts compartmentalize photosynthesis into light harvesting and carbon assimilation stages across membrane systems. Thylakoid membranes, intricate network of flattened discs stacking into grana interconnected by stroma lamellae, house photosystems II and I, cytochrome b6f complex and ATP synthase that convert light energy into ATP and NADPH through non-cyclic and cyclic electron transport, proton pumping and water splitting at oxygen-evolving complex. Those products are consumed in the aqueous phase surrounding thylakoids, the stroma, where the Calvin-Benson-Bassham cycle operates. Stromal soluble enzymes, including Rubisco large and small subunits, phosphoglycerate kinase, glyceraldehyde-3-phosphate dehydrogenase, fructose-1,6-bisphosphatase, aldolase and transketolase, fix CO2 onto ribulose-1,5-bisphosphate to generate 3-phosphoglycerate, reduced to triose phosphates using ATP and NADPH. Stroma also contains plastid DNA, 70S ribosomes, starch synthases, nitrite reductase, enzymes for fatty acid and amino acid synthesis, and antioxidant systems. High pH near 8.0 and Mg2+ elevation in illuminated stroma activate Rubisco via carbamylation and Rubisco activase, optimizing carbon fixation and preventing wasteful photorespiration.
Ref: Taiz et al., Plant Physiology and Development, 6th ed., Chapter 8: Photosynthesis – The Calvin Cycle in Stroma.
3-Phosphoglyceric acid (PGA) is the first stable product formed in the Calvin cycle.
Ref: NCERT Class 11 Biology Chapter 11: Photosynthesis in Higher Plants Photosynthesis - Significance and Bacterial Photosynthesis
Six turns of the Calvin cycle are needed to fix six molecules of CO₂ and produce one molecule of glucose.
Ref: NCERT Class 11 Biology Chapter 11: Photosynthesis in Higher Plants Photosynthesis - Significance and Bacterial Photosynthesis
The Calvin cycle produces G3P, which is later used to form glucose and other carbohydrates.
Ref: NCERT Class 11 Biology Chapter 11: Photosynthesis in Higher Plants Photosynthesis - Significance and Bacterial Photosynthesis
ATP provides the energy required, and NADPH supplies reducing power for CO₂ fixation in the Calvin cycle.
Ref: NCERT Class 11 Biology Chapter 11: Photosynthesis in Higher Plants Photosynthesis - Significance and Bacterial Photosynthesis
During the regeneration phase, RuBP is regenerated using ATP, allowing the Calvin cycle to continue.
Ref: NCERT Class 11 Biology Chapter 11: Photosynthesis in Higher Plants Photosynthesis - Significance and Bacterial Photosynthesis
The Calvin cycle takes place in the stroma of the chloroplast, where carbon fixation occurs.
Ref: NCERT Class 11 Biology Chapter 11: Photosynthesis in Higher Plants Chemiosmotic Hypothesis and Factors Affecting Photosynthesis
Oxygen is released during the light-dependent reactions, not the light-independent reactions.
Ref: NCERT Class 11 Biology Chapter 11: Photosynthesis in Higher Plants Chemiosmotic Hypothesis and Factors Affecting Photosynthesis
During the reduction phase of the Calvin cycle, ATP provides energy, and NADPH provides electrons to convert PGA into G3P.
Ref: NCERT Class 11 Biology Chapter 11: Photosynthesis in Higher Plants Chemiosmotic Hypothesis and Factors Affecting Photosynthesis
In C₃ plants, CO₂ fixation leads to the formation of 3-phosphoglyceric acid (PGA) as the first stable product.
Ref: NCERT Class 11 Biology Chapter 11: Photosynthesis in Higher Plants Chemiosmotic Hypothesis and Factors Affecting Photosynthesis
The first step of the Calvin cycle is carboxylation, where CO₂ is fixed by RuBP using the enzyme RuBisCO.
Ref: NCERT Class 11 Biology Chapter 11: Photosynthesis in Higher Plants Dark Reaction - Calvin Cycle - C3 Pathway
