Which molecule carries genetic information in cells?

• A. RNA
• B. DNA
• C. Protein
• D. Lipid

Answer: (B)

DNA stores genetic information in cells. The sequence of its nucleotides holds the instructions for making every protein and functional RNA, and its stable, complementary base-paired double-helix structure lets it be accurately copied during cell division so the information is passed on to new cells. While RNA is crucial for carrying instructions from DNA and for some functional roles within the cell, the hereditary blueprint in cellular life is stored in DNA, not in proteins or lipids. Proteins are the products of gene expression and do not serve as the long-term storage of genetic information, and lipids do not encode genetic information. (Note: some viruses use RNA as their genetic material, but viruses are not cells.) Therefore, DNA is the molecule that carries genetic information in cells.