Final answer:
Ribozymes are RNA molecules with catalytic properties similar to protein enzymes, and they lower activation energy to promote specific chemical reactions. They are fundamental to RNA processing and protein synthesis.
Step-by-step explanation:
An RNA molecule that can act as a catalyst and promote a specific chemical reaction is known as a ribozyme. These macromolecules are a type of ribonucleic acid (RNA) that catalyze reactions, similar to protein enzymes, by lowering the activation energy necessary for the reaction to occur. They are essential in various biological processes, including RNA splicing and protein synthesis.
While most enzymes in the human body are protein-based, ribozymes perform catalytic functions without being composed of amino acids. The discovery of these RNA catalysts provided novel insights into the chemical processes within cells and contributed to the understanding of early biochemical evolution, given their potential role in the hypothetical 'RNA world' where life may have originated.