Data suggest that rubisco ribulose- 1,5- bisphosphate carboxylase) makes up 10% of the total protein found in spinach leaves. Research elucidating the structure of rubisco shows that it has four active sites. Why, with four active sites, might there be such a large concentration of rubisco in plant matter?
A) Rubisco is a very slow enzyme; what it lacks in speed, it makes up in numbers.
B) Rubisco catalyzes four of the six reactions found in the Calvin cycle.
C) Three of the four active sites bind carbon dioxide; only one binds ribulose- 1,5- bisphosphate.
D) All heterotrophic organisms depend on plants, either directly or indirectly, for their food supply.

Question

Quizplus · Accepted Answer

Rubisco is indeed a very slow enzyme, which is why plants need a lot of it to efficiently fix carbon dioxide during photosynthesis.

Data Suggest That Rubisco Ribulose- 1,5- Bisphosphate Carboxylase) Makes Up