AP BIOLOGY

Detailed explanation-1: -The genetic code is a set of three-letter combinations of nucleotides called codons, each of which corresponds to a specific amino acid or stop signal. The concept of codons was first described by Francis Crick and his colleagues in 1961.

Detailed explanation-2: -The genetic code is made up of codons, which are three-letter chains of nucleotides. Each codon codes for one specific amino acid. The code determines the order in which amino acids are added to a polypeptide chain during protein synthesis. Therefore, the genetic code dictates the sequence of amino acids in a protein.

Detailed explanation-3: -Genetic Code Each gene’s code uses the four nucleotide bases of DNA: adenine (A), cytosine (C), guanine (G) and thymine (T)-in various ways to spell out three-letter “codons” that specify which amino acid is needed at each position within a protein.

Detailed explanation-4: -The genetic code includes 64 possible permutations, or combinations, of three-letter nucleotide sequences that can be made from the four nucleotides. Of the 64 codons, 61 represent amino acids, and three are stop signals. For example, the codon CAG represents the amino acid glutamine, and TAA is a stop codon.

Detailed explanation-5: -Three is the minimum number of nucleotides per codon needed to encode 20 amino acids.