Which macromolecule is primarily responsible for coding hereditary information and directing protein synthesis?

Which macromolecule is primarily responsible for coding hereditary information and directing protein synthesis?

• A. Carbohydrates; stored energy and structure
• B. Lipids; energy storage and membranes
• C. Nucleic acids; DNA carries genetic information and RNA helps in transcription and translation
• D. Proteins; enzymes and structural roles

Answer: (C)

The idea being tested is how genetic information is stored and used to make proteins. Nucleic acids are the only macromolecules whose sequences encode hereditary information. DNA holds the long-term genetic blueprint in its sequence of nucleotides. When a gene is expressed, this information is first copied into RNA in a process called transcription. The resulting RNA, especially messenger RNA, carries the coded instructions from DNA to the ribosome. There, during translation, the sequence on the RNA guides the assembly of amino acids into a protein, with help from transfer RNA and ribosomal RNA. This DNA-to-RNA-to-protein flow is why nucleic acids are central to both heredity and protein synthesis. Carbohydrates, lipids, and proteins have important roles in energy, structure, membranes, and function, but they do not store and transmit genetic information.

The idea being tested is how genetic information is stored and used to make proteins. Nucleic acids are the only macromolecules whose sequences encode hereditary information. DNA holds the long-term genetic blueprint in its sequence of nucleotides. When a gene is expressed, this information is first copied into RNA in a process called transcription. The resulting RNA, especially messenger RNA, carries the coded instructions from DNA to the ribosome. There, during translation, the sequence on the RNA guides the assembly of amino acids into a protein, with help from transfer RNA and ribosomal RNA. This DNA-to-RNA-to-protein flow is why nucleic acids are central to both heredity and protein synthesis. Carbohydrates, lipids, and proteins have important roles in energy, structure, membranes, and function, but they do not store and transmit genetic information.