[q-bio.PE]. The ribosome is responsible for protein synthesis in all cells, and is the largest energy consumer in the cell.
![A symbiotic scenario for co-evolution of the ribosome and the replicase. Two variations of the scenario are depicted, whereby the peptidyltransferase center (PTC) and the replicase (REP) ribozymes are encoded by distinct (A) or the same (B) RNA molecule. The figure depicts three major stages of cellular evolution from the primordial RNA world (left) to the intermediate RNA-protein world (center) and the last universal cellular ancestor (LUCA, right). The major events occurring during each stage are briefly described in the corresponding information boxes at the bottom of the figure. -- [q-bio.PE]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/08/The-selfish.png?resize=1200%2C712&ssl=1)
[q-bio.PE]. The ribosome is responsible for protein synthesis in all cells, and is the largest energy consumer in the cell.