What is a codon and how many bases does it contain? A codon is a sequence of three nucleotides that codes for a specific amino acid or serves as a start or stop signal for protein synthesis. There are 64 possible codons, 61 of which code for amino acids and three of which are stop codons that terminate the translation process. Each codon is composed of a sequence of three nucleotide bases that are read by ribosomes during protein synthesis. The order and arrangement of these bases determine the order and arrangement of the amino acids in a protein chain. There are four different nucleotides that make up DNA and RNA – adenine (A), guanine (G), cytosine (C), and thymine (T) in DNA and uracil (U) in RNA. The specific sequence of these nucleotides codes for specific proteins, with each codon encoding for one of the 20 different amino acids used by living organisms. Codons make up the genetic code, which is the set of rules that governs how the nucleotide sequence of DNA and RNA is translated into amino acids. Understanding codons and their role in protein synthesis is crucial for understanding genetics and molecular biology. References: - Alberts, B., Johnson, A., Lewis, J., Raff, M., Roberts, K., & Walter, P. (2002). Molecular biology of the cell. Garland Science. - Lodish, H., Berk, A., Zipursky, S. L., Matsudaira, P., Baltimore, D., & Darnell, J. (2000). Molecular cell biology. WH Freeman.