Fascinating animation of DNA replication etc

[OwlHoot]

in real time.

http://video.google.com/videoplay?do...46742655575670

The replication and protein synthesis starts about 1/5th of the way in, after a short section on chromosomes curling up.

[Churchill]

Fantastic, very impressive.

[TimberWolf]

Kewl!

Just to add some facts about what's going on there. I've got a book that describes the basics. The first part of the film shows DNA being coiled and coiled and super-coiled many times over. Starting with a double helix strand of DNA perhaps a metre long that consists of around 3 billion base pairs (Adenine, Guanine, Cytosine, Thymine) until X shaped chromosomes are formed. Most of the time DNA floats around uncoiled in the nucleus, but it is coiled up before cell division. Hmm, if I leave two bits of string lying around they soon end up in a horrible mess, it's incredible that a metre long string in a tiny cell's nucleus doesn't get hopelessly knotted, let alone can be coiled up like that.

About the genetic code. There are the only 4 letters in the genetic alphabet making up our DNA - AGCT. That's it, all our genetic code is made up just these four letters. It turns out all our different proteins (30,000 or so from an infinite possible set) can be built from a pallet of just 20 different amino acids, so the genetic code only needs to encode 20 different 'words' using these 4 letters. It turns out we know how she does it. As said in the film, nature uses three letters per word (codon), meaning 4^3=64 different words are possible, but we only need 20 words, one for each amino acid, plus a few more for start and stop codes. Nature uses all 64 words available though, and all words are 3 letters long. This is very simple and elegant and it turns out if common mistakes do occur, the mistake is likely to code for the same amino acid (since perhaps 3 or words describe the same amino acid), and other mistakes will likely code for similar amino acids.

Cool eh, not only the simplicity and elegance of nature but that such a fundamental process has been figured out. Natures little programming code busted. The letters and words at least, I'm so sure grammar or whole sentences are well understood.

I'm sure someone who knows what they're talking about could describe it better.

[Churchill]

How the **** can it be a metre long?

[Troll]

Fascinating stuff

What is missing is the orchestration of events – what instructs the processes to commence?

[Churchill]

Fascinating stuff

What is missing is the orchestration of events – what instructs the processes to commence?

When a mummy and a daddy love each other very much...

[TimberWolf]

How the **** can it be a metre long?

I think they said they were 6 foot long in the film, though my book says a metre. There are 3 billion base pairs (in 23 chromosomes) in each cell and that's going to be a pretty long (and very thin) strand. We have 100 trillion cells (needing around 200 to covering the dot in this i) containing these chromosomes too. Aint nature prolific.

[TimberWolf]

Fascinating stuff

What is missing is the orchestration of events – what instructs the processes to commence?

The incredible thing is there's no intelligence involved despite appearances, just masses of copying over and over, and over and over. Masses of duplication. Things bump into each other and if they fit the next process can follow.

[DimPrawn]

The incredible thing is there's no intelligence involved despite appearances, just masses of copying over and over, and over and over. Masses of duplication. Things bump into each other and if they fit the next process can follow.

Sounds like the same process used to write software at Wipro and InfoSys.

[SupremeSpod]

Sounds like the same process used to write software at Wipro and InfoSys.

Yup, it's known as "The Zillion Monkeys" approach!