Friday, October 2, 2009
Persons suffering from colour blindness have difficulty in distinguishing red from green. It is common trait and more common in males than females. It is because Y chromosome is inert for this trait in males. Only one gene of this trait will render a colour blind man. In case of woman it must have two genes for this trait to become colour blind. There are rare cases of colour blindness in women.This trait of colour blindness can easily be detected by using special charts made up of a number of coloured dots so arranged that colour blind persons see different pattern than other persons do.
The word code is used several times to refer to the information stored in DNA and ultimately translated into amino acid sequence of Proteins.
The genetic code is conceptually similar to Morse code. One set of symbols (bases in nucleic acids, dots and dashes in Morse Code) can be translated into another set of symbols (amino acids in Proteins).
Genetic code was three bases to specify each amino acid. There are four different bases in DNA: adenine (A), Cytosine (C), guanine (G) and thymine T. there are also four bases in RNA: adenine, cytosine, guanine and uracil (u). But there are 20 different amino acids in Proteins, so the bases cannot serve as one to one code for amino acid.
Genetic code might use short sequence of bases to encode each amino acid, just as Morse Code uses a short sequence of dots and dashes to encode the letters of alphabet.