DNA is a continuous long double helical structure that turns into genes or proteins and chromosome by breaking itself appropriately during cell division.
- The three main functions of DNA are as follows.
- To form proteins and RNA. It is RNA that helps in passing genetic information from nucleus to the cytoplasm, hence referred as m-RNA.
- To exchange the genetic material of parental chromosomes during meiotic cell division.
- To facilitate occurring mutations and even mutational change in a single nucleotide pair, called point mutation.
A primary function of RNA is to provide a copy of DNA sequence, and to move out of nucleus (if a cell is a eukaryote). Once RNA is created, is serves a number of functions:
1.as mRNA, provides a template for protein synthesis by ribosome, with a sequence of amino acids corresponding to the sequence stored in DNA;
2.as rRNA, makes about half of the ribosome structure (the other half being proteins);
3.as tRNA, transports amino acids to a ribosome for inclusion in a polypeptide chain being synthesized;
4.some RNAs have enzymic activity (ribozymes), and act as enzymes;