U3 AOS 2: Rubisco in C3, C4 and CAM Photosynthesis

Front

What is Rubisco?

Back

Rubisco is ribulose biphosphate carboxylase-oxygenase, an enzyme involved in carbon fixation.

Front

What is carbon fixation?

Back

Carbon fixation is the process of converting inorganic carbon (CO2) into organic carbon compounds.

Front

What are the reactants in the carbon fixation process?

Back

3 x CO2 and 3 x RuBP (five-carbon).

Front

What are the products of the carbon fixation process?

Back

6 x 3-PGA (three-carbon).

Front

What is the role of NADPH in photosynthesis?

Back

NADPH is used in the reduction phase to convert 6 x 3-PGA into 6 x G3P.

Front

What happens to G3P in photosynthesis?

Back

1 x G3P is used to form glucose, while the rest is used in regeneration.

Front

What is photorespiration?

Back

Photorespiration is a process where Rubisco reacts with O2 instead of CO2, leading to a loss of fixed carbon.

Front

What is the difference between C3 and C4 plants?

Back

C3 plants fix carbon in a single cell, while C4 plants fix carbon spatially in two cells, using PEP carboxylase.

Front

What is PEP carboxylase?

Back

PEP carboxylase is an enzyme that fixes carbon in C4 plants, forming oxaloacetate (four-carbon).

Front

What is the role of stomata in photosynthesis?

Back

Stomata are pores that regulate gas exchange and water loss in plants.