Data Suggest That Rubisco (Ribulose-1,5-Bisphosphate Carboxylase)makes Up 10% of the Total

Multiple Choice

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) All heterotrophic organisms depend on plants,either directly or indirectly,for their food supply.
B) Rubisco is a very slow enzyme;what it lacks in speed,it makes up in numbers.
C) Rubisco catalyzes four of the six reactions found in the Calvin cycle.
D) Three of the four active sites bind carbon dioxide;only one binds ribulose-1,5-bisphosphate.