The Chemistry of Biology Practice Test 2026 - Free Biology Chemistry Practice Questions and Study Guide

Genetic information is stored in a molecule that can be accurately copied and kept stable over time. DNA fits this role because its structure provides a durable, long-term repository for the instructions that specify how an organism builds and maintains itself. The double-helix design with complementary base pairing means each strand can serve as a precise template for creating the other, enabling faithful replication during cell division. The sequence of bases encodes genes and regulatory elements, and the chemistry of DNA is well-suited to resisting degradation long enough to pass information to offspring.

RNA, while essential for reading and transmitting genetic information (and for many cellular tasks), is generally less stable and is used for temporary messages and catalytic roles rather than long-term storage. ATP stores energy, not hereditary information. Proteins perform a wide range of cellular functions, but they do not serve as heritable information stores.