Final answer:
DNA is used as hereditary material instead of RNA because DNA has mechanisms to repair mutations, maintaining genetic stability across generations, which RNA lacks.
Step-by-step explanation:
DNA is used as hereditary material rather than RNA because it has repair mechanisms that maintain its stability over generations. RNA, which does play a crucial role in protein synthesis, does not have comparable repair mechanisms, making it less suitable for long-term genetic information storage. While RNA can carry genetic information, as seen in some viruses, it is generally used for transferring information from DNA to the protein-making machinery of the cell, not for storing all of the hereditary information for an organism.
One of the reasons DNA is better suited for genetic information storage is its structural stability and the presence of built-in repair processes. When DNA mutates, which can occur due to various environmental or internal factors, cells utilize several pathways to remedy errors. This repair capability is crucial for maintaining the genetic information intact as it is passed from parent to offspring. In contrast, although RNA contains genetic information, particularly in the case of some viruses, its lack of a robust repair mechanism makes it less stable and thus less suitable for storing the hereditary information of most living organisms over multiple generations.