The Calvin Cycle

This set of flashcards contains key vocabulary terms and definitions related to the processes and components of the Calvin cycle, focusing on carbohydrate synthesis in photosynthesis.

Calvin Cycle

A series of enzymatic reactions that synthesize carbohydrates from carbon dioxide (CO₂).

Carboxylation

The first phase of the Calvin cycle where CO₂ is added to a 5-carbon molecule, RuBP.

Rubisco

An enzyme that catalyzes the addition of CO₂ to RuBP; known as ribulose bisphosphate carboxylase-oxygenase.

RuBP

Ribulose 1,5-bisphosphate, a 5-carbon compound that combines with CO₂ in the Calvin cycle.

3-PGA

3-phosphoglycerate, a 3-carbon compound formed when CO₂ is added to RuBP.

Triose Phosphates

The 3-carbon sugars G3P and DHAP produced during the Calvin cycle.

ATP

A molecule that provides energy for the phosphorylation of 3-PGA in the Calvin cycle.

NADPH

A reducing agent that donates electrons and protons in the Calvin cycle.

G3P

Glyceraldehyde 3-phosphate, a product of the Calvin cycle that may be converted into glucose.

DHAP

Dihydroxyacetone phosphate, another product of the Calvin cycle.

Regeneration of RuBP

The final phase of the Calvin cycle where 3-carbon compounds are reorganized to produce RuBP.

Carbon Input

The entry of CO₂ into the Calvin cycle.

Photosynthesis

A metabolic process that converts CO₂ and water into carbohydrates using sunlight.

Starch

The storage form of carbohydrates produced when excess carbohydrates accumulate in the cell.

Radioactive CO₂

CO₂ labeled with a radioactive isotope used by Calvin and colleagues to trace carbon compounds.

Enzymatic Reactions

Chemical processes in the Calvin cycle that are facilitated by enzymes.

Cyclic Photophosphorylation

A process that helps explain the ratio of NADPH to ATP used in the Calvin cycle.

Photosynthetic Cells

Cells in plants that perform photosynthesis and produce carbohydrates.

Osmosis

The movement of water into cells that can occur due to high concentrations of soluble sugars.

Chemical Reactions

The processes that connect the labeled compounds identified in experiments on the Calvin cycle.

Energy Transfer

The process in the Calvin cycle where energy from ATP and NADPH is used to convert 3-PGA into triose phosphates.