Calvin Cycle Carbon Fixation, Rubisco, and Rubisco Activase

The video tutorial explores the Calvin Cycle, focusing on the enzyme Rubisco, its role in carbon fixation, and its dual function as a carboxylase and oxygenase. It discusses the regulation of Rubisco, including the effects of pH, Rubisco Activase, and CA1P. The tutorial also delves into the structure of Rubisco's active site, emphasizing the importance of the carbamate group for its activation. Despite Rubisco's slow turnover rate, its abundance in plants compensates for this, making it crucial for photosynthesis.

What is the primary role of Rubisco in the Calvin Cycle?

• To produce oxygen

• To regenerate RuBP

• To fix carbon dioxide

• To reduce 3-PGA

Why is Rubisco considered a slow enzyme?

• It has a high turnover number

• It is not abundant in plants

• It has a low turnover number

• It requires a lot of energy

How do plants compensate for Rubisco's slow turnover rate?

• By reducing RuBP concentration

• By using alternative enzymes

• By producing more Rubisco

• By increasing the temperature

Which factor does NOT regulate Rubisco activity?

• CA1P

• Light intensity

• Rubisco Activase

• pH of the environment

What is the role of Rubisco Activase?

• To inhibit Rubisco

• To remove inhibitory RuBP

• To increase pH

• To decrease enzyme concentration

What is essential for Rubisco's activation?

• Low carbon dioxide levels

• High oxygen levels

• A carbamate group

• A free lysine group

What happens to Rubisco at night?

• It fixes more carbon dioxide

• It is inhibited by RuBP

• It becomes more active

• It produces more glucose