A three-nucleotide sequence of DNA or RNA that contains information is called a/an
amino acid.
polypeptide.
nucleotides.
codon.
The Correct Answer and Explanation is:
The correct answer is codon.
A codon is a three-nucleotide sequence of DNA or RNA that encodes information used in protein synthesis. In the process of translation, codons are read by ribosomes in order to assemble amino acids into a polypeptide chain. These sequences of nucleotides form the genetic code, which is universal across most living organisms.
To understand the role of codons, it’s important to first examine the structure of nucleic acids like DNA and RNA. Nucleotides, the building blocks of these molecules, consist of three components: a sugar, a phosphate group, and a nitrogenous base. In DNA, the nitrogenous bases are adenine (A), thymine (T), cytosine (C), and guanine (G), while in RNA, thymine is replaced by uracil (U). When these bases combine in groups of three, they form codons, each of which specifies a particular amino acid or a stop signal during protein synthesis.
For example, in mRNA, the codon AUG codes for the amino acid methionine, which is often the first amino acid incorporated into a protein during translation. Other codons, such as UAA, UAG, and UGA, are stop codons, signaling the termination of the protein synthesis process.
The genetic code is read in triplets, with each set of three nucleotides encoding a specific amino acid, the building block of proteins. The sequence of amino acids in a polypeptide chain determines the structure and function of proteins. This coding system is highly precise, allowing cells to translate genetic information into functional proteins that drive the processes of life.
In summary, a codon is a sequence of three nucleotides in DNA or RNA that carries the information required for building proteins, playing a central role in the genetic code.