Proteins are not the only substances that are synthesized directly from data within the DNA. Some forms of RNA are specialized, and also have their formula encoded directly in digital DNA formulae. Not all types of RNA are temporary intermediate forms with their form depending on whatever DNA they are copying. There are certain forms of RNA that have a particular form that is the same across all individuals. Some of these special-purpose RNA forms are,
1. tRNA - transfer RNA
2. rRNA - ribosome RNA
There are exactly 20 forms of tRNA, one each transfer a particular amino acid. tRNA molecules contain about 75-80 bases. tRNA recognizes one of the 64 triplets, and matches it one of the 20 amino acids. Since there are 20 tRNA types, and not 64, each tRNA molecule has to recognize more than one triplet ordering as a match. The DNA code contains multiple repetitions of codes for tRNA and rRNA. About 280 copies are spread over 5 chromosomes. Presumably, this allows each cell to make multiple copies of tRNA and rRNA molecules at once from its single copy of the DNA.
1. tRNA - transfer RNA
2. rRNA - ribosome RNA
There are exactly 20 forms of tRNA, one each transfer a particular amino acid. tRNA molecules contain about 75-80 bases. tRNA recognizes one of the 64 triplets, and matches it one of the 20 amino acids. Since there are 20 tRNA types, and not 64, each tRNA molecule has to recognize more than one triplet ordering as a match. The DNA code contains multiple repetitions of codes for tRNA and rRNA. About 280 copies are spread over 5 chromosomes. Presumably, this allows each cell to make multiple copies of tRNA and rRNA molecules at once from its single copy of the DNA.