Nukleotit

A nucleotide is the basic building block of nucleic acids, such as DNA and RNA. Each nucleotide consists of three components: a nitrogenous base, a five-carbon sugar, and at least one phosphate group. The nitrogenous bases in DNA are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) replaces thymine. The five-carbon sugar is deoxyribose in DNA and ribose in RNA. The phosphate group links the nucleotides together to form a long chain.

Nucleotides play crucial roles in cellular processes. They are the monomers that polymerize to form DNA, which stores genetic information, and RNA, which is involved in protein synthesis and gene regulation. Adenosine triphosphate (ATP) is a vital nucleotide that serves as the primary energy currency of the cell, powering various metabolic reactions. Other nucleotide derivatives are involved in signaling pathways and as coenzymes. The sequence of nucleotides in DNA determines the genetic code, dictating the order of amino acids in proteins and thus the traits of an organism. The structure of nucleotides, with their specific base pairing rules (A with T in DNA, A with U in RNA, and G with C in both), is fundamental to DNA replication and transcription.