>> ^rychan:

That can't really be very pure DNA, though, right? DNA is a pretty tiny fraction of your cells by volume / weight, and the soap might dissolve some parts of the cell but not all of it.


No, it's not pure DNA. It's DNA + histones (the proteins associated with DNA).

I think he was referring to Lamarckism - the idea the the acquired traits of an individual were passed on to their offspring (ie. the stretching of a giraffe's neck to reach higher branches caused it's neck to lengthen, which passed to the offspring resulting in longer and longer necks.)

After Darwin, Lamarckism lost ground continuously. It has only been in the last 50 years or so that we have begun to have hints that there is a small kernel of truth in it as evidenced by epigenetic phenomena.>> ^carneval:

>> ^L0cky:
The idea that the changes you make to your body will be passed on is a very old one, but since Darwin it's been pretty much ridiculed. For it to come back is pretty big stuff.

I don't think that it's been really ridiculed, epigenetic phenomena are accepted in the scientific community as very real, testable changes to the DNA and DNA packaging structures (histone acetylation/deacetylation, histone methylation, DNA methylation, etc).

>> ^L0cky:

The idea that the changes you make to your body will be passed on is a very old one, but since Darwin it's been pretty much ridiculed. For it to come back is pretty big stuff.


I don't think that it's been really ridiculed, epigenetic phenomena are accepted in the scientific community as very real, testable changes to the DNA and DNA packaging structures (histone acetylation/deacetylation, histone methylation, DNA methylation, etc).

these are great. i wish he'd make a messy version, too, with a slightly more realistic amount of other molecules bouncing around... just so it doesn't look like these things are magically directed to the site they're needed (proteins that attach with and around histones for the first one, accessory proteins in the replication fork, and of course the A,C,G,T's that are coming out of nowhere in the replication fork).

It's showing a computer animated representation of chromatin (DNA) condensing in order for a cell to replicate. At the beginning of the process we see a simple double-strand of DNA. The little critters that attach to it are called histones. The DNA coils around these and then the histones link together to further coil the DNA. After that the details get fuzzy for me, I had medical biochem and genetics last year.

Interestingly, if you were to stretch out the DNA molecule in a human cell into one continuous strand it would be about 3 meters long, depending on whose research you look at.

Amazing.

If you add up all the DNA in all the cells in the size of an average human you could go from the earth to the sun almost 70 times!