Reactions involved in the light-independent reactions of photosynthesis constitute the _______.
a. Citric acid cycle
b. Entner-Doudoroff pathway
c. Calvin-Benson cycle
d. pentose phosphate pathway

Verified step by step guidance

1. Understand that photosynthesis consists of two main stages: light-dependent reactions and light-independent reactions.
2. Recall that the light-dependent reactions capture light energy to produce ATP and NADPH, which are then used in the light-independent reactions.
3. Identify that the light-independent reactions are responsible for fixing carbon dioxide into organic molecules, a process known as carbon fixation.
4. Recognize that the cycle responsible for carbon fixation in photosynthesis is called the Calvin-Benson cycle.
5. Match the correct answer choice to the Calvin-Benson cycle, which corresponds to option c.

Key Concepts

Light-Independent Reactions of Photosynthesis

These reactions, also known as the dark reactions, do not require light directly and use ATP and NADPH produced in the light-dependent reactions to fix carbon dioxide into organic molecules. They occur in the stroma of chloroplasts and are essential for synthesizing glucose.

Calvin-Benson Cycle

The Calvin-Benson cycle is the primary pathway of carbon fixation in photosynthesis, converting CO2 into glucose using ATP and NADPH. It involves three phases: carbon fixation, reduction, and regeneration of the CO2 acceptor molecule, ribulose bisphosphate.

Other Metabolic Pathways (Citric Acid Cycle, Entner-Doudoroff Pathway, Pentose Phosphate Pathway)

These pathways are involved in cellular metabolism but are distinct from photosynthesis. The citric acid cycle is part of aerobic respiration, the Entner-Doudoroff pathway is an alternative glycolytic route, and the pentose phosphate pathway generates NADPH and ribose sugars, not directly fixing CO2.