Why might Rubisco have evolved with an inability to distinguish between CO₂ and O₂? A)Rubisco may have evolved at a time when atmospheric O₂ levels were virtually nonexistent. B)Rubisco may have evolved at a time when atmospheric CO₂ levels were virtually nonexistent. C)Rubisco evolved when atmospheric O₂ levels were high. D)Rubisco possesses four subunits. E)Rubisco denatures due to photorespiration.

Question

Quizplus · Accepted Answer

Rubisco likely evolved before atmospheric CO₂ levels became significant in the atmosphere. Therefore, there was no selective pressure for the enzyme to distinguish between CO₂ and O₂.

Why Might Rubisco Have Evolved with an Inability to Distinguish