Question

RNA strand synthesis without protein based enzymes may not be a major bottleneck in the evolution of life (RNA world hypothesis) because RNA strands may be polymerized from ribonucleotides on the surface of clay mineral catalysts. Which of the following are observations that have been made that offer additional routes for making RNA strands without the involvement of protein based enzymes further suggesting that this is a relatively easy step along the evolution of life?

1) dilute solutions of ribonucleotides when frozen and left for sometime show evidence of formation of RNA strands
2) dilute solution of ribonucleotides when mixed with DNA form ribonucleotides
3) none of the statements are known pieces of evidence
4) all of the statements are known pieces of evidence

Answer 1

The first statement regarding ribonucleotides forming RNA strands when frozen and thawed is true evidence for RNA synthesis without enzymes, while the second statement is inaccurate. Therefore, only the first statement is true regarding the RNA world hypothesis.

Step-by-step explanation:

In the RNA world hypothesis, it's suggested that RNA was the first biochemical molecule to evolve and that early life was based solely on RNA. Several pieces of evidence support the idea of RNA strands forming without the involvement of protein-based enzymes. To address the given options, the first statement is observed evidence. Studies have found that when dilute solutions of ribonucleotides were frozen and subsequently thawed, there were indications of RNA strand formation. This suggests that RNA polymerization could occur under prebiotic conditions. However, the second statement is inaccurate as mixing ribonucleotides with DNA does not lead to the formation of ribonucleotides, as they are already present. Hence, the correct answer is that only the first statement is a known piece of evidence supporting alternative routes of RNA strand formation without enzymatic involvement.