Which of the following molecules is thought to have acted as the first enzyme in early life on earth?

Which of the following molecules is thought to have acted as the first enzyme in early life on earth?
A . Protein
B . RNA
C . Triglycerides
D . Phospholipids
E . DNA

View Answer

Answer: B

Explanation:

Some RNA molecules in extant organisms have enzymatic activity; for example, the formation of peptide bonds on ribosomes is catalyzed by an RNA molecule. This and other information have led scientists to believe that the most likely molecules to first demonstrate enzymatic activity were RNA molecules.