Final answer:
Arginine is coded by six codons due to the degeneracy of the genetic code, which includes 64 possible codons for 20 common amino acids.
Step-by-step explanation:
The number of codons that code for the amino acid arginine is six. This is due to the fact that the genetic code is degenerate, which means that multiple codons can specify the same amino acid. Specifically, for arginine, the codons are CGU, CGC, CGA, CGG, AGA, and AGG. This redundancy allows for variations in the third nucleotide position, commonly referred to as the wobble position.
In the context of the genetic code, there are 64 possible codons that can be formed from any combination of three nucleotide bases out of the four nucleotides that make up the nucleic acids. Of these 64 codons, 61 code for amino acids, and the remaining are stop codons. Each codon sequence is comprised of three nucleotides and is specific for one of the 20 common amino acids found in proteins or a stop signal during protein synthesis.