The correct option is A.
The RNA that is most likely to have been involved in self-replication processes in the early stages of life's evolution is not tRNA, but rather certain ribozymes like RNase P. Therefore, "CRNA," does not correspond to any known RNA type in this context. The answer is A, "tRNA," as it was not primarily involved in self-replication but rather in protein synthesis, while certain ribozymes, like RNase P, played a crucial role in early self-replication processes.
The earliest self-replicating information-containing molecule in the theory of abiogenesis is indeed believed to be RNA (Ribonucleic Acid). RNA is a versatile biomolecule that plays several essential roles in the cell, one of which is carrying genetic information.
However, when discussing self-replication, we need to focus on a specific type of RNA that possesses catalytic activity, allowing it to participate in self-replication processes.
The RNA that fits this description is known as Ribozyme, a term coined by Thomas Cech and Sidney Altman, who received the Nobel Prize in Chemistry in 1989 for their discoveries related to RNA catalysis.
Ribozymes are RNA molecules that can catalyze chemical reactions, just like enzymes, which are typically proteins that facilitate various biochemical reactions in living organisms.
One of the most well-known ribozymes is the ribosomal RNA (rRNA) found in the ribosome, a cellular structure responsible for protein synthesis.
However, rRNA's primary function is to assist in protein synthesis rather than self-replication.
The ribozyme that is most relevant to the idea of RNA self-replication is the RNA enzyme known as the Ribonuclease P (RNase P).
RNase P is responsible for processing tRNA (Transfer RNA) precursors into their mature functional forms. While tRNA's primary role is to carry amino acids during protein synthesis, RNase P is a ribozyme within the cell that catalyzes the cleavage of specific RNA sequences during tRNA maturation.
This catalytic activity of RNase P is essential for tRNA function and, in essence, represents an early example of RNA catalysis.
The answer is tRNA.
The complete question is here:
The earliest self-replicating information containing molecule is theorized to be RNA. Which type of RNA that we have learned about in all likelihood used to be able to self-replicate?
HINT: Which RNA does more than carry a message?
A. tRNA
B. CRNA