Wired Magazine recently asked some "Big Questions" in the cover story. This is one of them.
Details:
http://www.wired.com/wired/archive/15.02/bigquestions.html?pg=3#dna
2007-03-06 03:20:58 · 3 answers · asked by Rafe Furst 1 in Science & Mathematics ➔ Biology
other answer has exons / introns mixed up. Exons are the part that codes for proteins. Introns are non-coding spacers between exons within a gene. Then there are non-coding regions of DNA between genes. Introns help to attract the 'machinery' of protein synthesis (ribosomes, etc.), they help in folding DNA correctly so that the correct 'machinery' is added, etc. Non-coding regions between genes have many hypothetical uses, but it is not known for sure what they do. Guesses are that they are leftovers - they used to be genes, but are no longer used, also another guess is that they are parasitic DNA that have inserted themselves into the genome, but arent used for anything. Also, there are other regions that perform functions. Telomeres are the strings of DNA at the end of a chromosome; they are used to keep the chromosome stable and are also involved in apoptosis - the process by which a cell decides that it can no longer divide, and otherwise should kill itself (this has implications is many types of cancer, where cancerous cells continually divide, and never get the message to stop dividing).
2007-03-06 03:58:04 · answer #1 · answered by Devin S 2 · 0⤊ 0⤋
noncoding DNA often serves regulatory purposes whether spatially or sequence-specific. Promoters for transcription are included in "noncoding" DNA and are recognized as significantly important pieces of DNA. Also the noncoding DNA portions make up centromeres, telomeres, and histone binding sites that are all absolutely necessary for proper chromosome function as well as cellular regulation.
2007-03-06 03:51:52 · answer #2 · answered by btpage0630 5 · 2⤊ 0⤋
It's a way of preventing mutations. Humans have long sequences of non-coding DNA called Introns. Exons contain the information needed to code signals. These are spliced together after transcription. The more "Junk" DNA the less of a chance you have a of mutation occuring from damage like getting hit by radiation
2007-03-06 03:26:23 · answer #3 · answered by foxhound34 3 · 1⤊ 1⤋