geenikoodin

Geenikoodin, also known as genetic code, is the set of rules by which information encoded within genetic material (DNA or RNA sequences) is translated into proteins. The genetic code is universal, meaning it is the same across all known organisms. It consists of 64 codons, each composed of three nucleotides, which correspond to specific amino acids or stop signals.

The genetic code is read in the 5' to 3' direction along the mRNA strand. Each codon is read by a ribosome, which then assembles the corresponding amino acid into a growing polypeptide chain. The process begins with the initiation codon, usually AUG, which codes for the amino acid methionine. The chain continues until a stop codon (UAA, UAG, or UGA) is encountered, at which point translation terminates.

The genetic code is degenerate, meaning that multiple codons can code for the same amino acid. This redundancy allows for some flexibility in the genetic material, as mutations in the third position of a codon often do not change the resulting amino acid.

The genetic code is not only crucial for protein synthesis but also plays a role in other biological processes, such as RNA splicing and editing. Understanding the genetic code is fundamental to fields like molecular biology, genetics, and biotechnology.