What is the primary function of DNA?

The primary function of DNA is to provide genetic information. DNA, or deoxyribonucleic acid, is the molecular blueprint for all living organisms. It carries the instructions necessary for growth, development, functioning, and reproduction. This genetic information is encoded in the sequence of nucleotide bases (adenine, thymine, cytosine, and guanine) that make up the DNA strand.

The structure of DNA allows it to store vast amounts of information that can be copied and passed on during cell division, ensuring that genetic traits and characteristics are maintained from one generation to the next. This function is fundamental to the processes of heredity, as well as to the expression of genes that contribute to the organism's phenotype.

In contrast, while energy for cellular activities is critical, it primarily comes from molecules like glucose and ATP, not DNA. Cellular respiration involves converting this energy, but it does not involve DNA's primary function. Similarly, DNA does not directly assist in cellular respiration or store proteins; instead, it codes for the synthesis of proteins, which are constructed from amino acids based on the information contained in genes. This distinction emphasizes the unique and essential role of DNA in biological systems.