Final answer:
Nucleotides are the basic units of nucleic acids like DNA and RNA, consisting of phosphate groups, pentose sugars, and nitrogenous bases. They play a vital role in storing genetic information and in biological processes such as energy transfer as seen in ATP.
Step-by-step explanation:
Nucleotides are the fundamental building blocks of nucleic acids, which include DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). A nucleotide is composed of three parts: a phosphate group, a pentose sugar, and a nitrogen-containing base. The sequencing of these nucleotides along a DNA or RNA strand constitutes genetic information essential for cellular functions and heredity. Additionally, the specific sequence of nucleotides within DNA forms its primary structure, which is crucial for the accurate replication and transcription of genetic material.
The pentose sugar in DNA is deoxyribose, while in RNA, it is ribose. There are also differences in the nitrogenous bases between DNA and RNA. DNA contains adenine (A), cytosine (C), guanine (G), and thymine (T), whereas RNA substitutes uracil (U) for thymine. During transcription, a segment of DNA is copied into RNA by the RNA polymerase enzyme, using nucleotide triphosphates as substrates and assembling them in the order dictated by the DNA template.
Nucleotides also function beyond the structure of nucleic acids. For instance, ATP (adenosine triphosphate) serves as the main energy currency of the cell, highlighting the importance of nucleotides in various biological processes.