We know genes or DNA molecules stores biological information and transfers these information from generation to generation in species. How the information is encoded in DNA? We can compare it with electronic digital coding and understand.
In digital memory , the two symbols 0 and 1(bit) are basic elements. In DNA, four elements adenine(A), cytosine (c), guanine(G) and uraul (U) are the fundamental units(chemical) to represent bio-info.
In digital, 8 bit (letters) words are used and they are called bytes. 2^ 8 = 256 symbols can be encoded using 8 bits system. (today 32 bits, 64 bits are also common). example:
"A" is represented by 01000001
"=" is represented by 00111101
In DNA, out of four, letters(ACGU), three letters are used to form words called codons. So, 4^3 = 64 symbols can be represented in this way. There are 20 amino acids using which variety of proteins are built. The proteins are basic building blocks of our body. Different set of these three letters codons represents different amino acids.
example
codon aminoacid
GCU Alanine
ACG threonine
GAG glutamale
...........................
...........................
When we type A=B, in the computer keyboard, the computer reads the bytes, understand and executes the command.
Similarly, our body cells read the three letter codons in the DNA, and according to the template they build various proteins using amino acids Thus our body is constructed and functions
Blue print for a building
A tune (composition) for a song
Digital coding for a computer,
DNA for life
DNA, out of four letters (ACGU)