Final answer:
The main role of DNA is to provide instructions on how to build proteins, which are the functional molecules essential for life processes. These instructions are encoded in the DNA sequence and passed on from generation to generation.
Step-by-step explanation:
The main role of DNA is to provide instructions on how to build proteins. DNA, or deoxyribonucleic acid, is a type of nucleic acid that carries the cell's genetic blueprint and contains the encoded instructions necessary for making proteins. These instructions are found in the sequence of nitrogen bases (adenine, thymine, guanine, and cytosine) along the DNA strand. Each group of three bases, known as a codon, corresponds to a specific amino acid or a start/stop signal during protein synthesis. The central dogma of molecular biology states that DNA is transcribed into RNA, which is then translated into proteins, the functional molecules that perform most life functions.
Nucleotides, the building blocks of nucleic acids, are composed of a sugar molecule, a phosphate group, and a nitrogen base. In DNA, these nucleotides form a double helix structure held together by bonds between complementary bases. DNA is organized into chromosomes within the cell, and it is during cell division that DNA is replicated and passed from parents to offspring, ensuring the continuation of genetic information.