What are nucleotides best described as?

Nucleotides are best described as the building blocks of nucleic acids, which include DNA and RNA. Each nucleotide consists of three components: a phosphate group, a five-carbon sugar (ribose in RNA and deoxyribose in DNA), and a nitrogenous base (which can be adenine, thymine, cytosine, guanine, or uracil). The sequence and type of nucleotides in a nucleic acid molecule determine the genetic information and functions of that molecule.

In the context of nucleotides, they play a critical role in storing and transmitting genetic information. In DNA, the specific order of nucleotides encodes the instructions for synthesizing proteins, which are essential for various cellular functions. During processes such as replication and transcription, nucleotides are assembled to form long chains that create the structure of nucleic acids.

The other options do not accurately capture the role of nucleotides. Proteins are composed of amino acids and serve entirely different functions within cells. Simple sugars, such as glucose, play a role in energy metabolism rather than forming nucleic acids. Energy-carrying molecules like ATP (adenosine triphosphate) do involve nucleotides but are a specific type