> - Blood is far from being that dense, but I'll assume you mean to calculate a theoretical limit.
There are more ways of having cells arranged, I explicitly mentioned red blood cells because they are exceptional in not containing any DNA, but any chunk of tissue with that volume would do.
> If you use the whole of a cell's DNA to encode information, the cell will die. It can't be used to freely encode information like a hard disk.
Yes, that's obvious, but a cell's DNA does hold that much information, it's just not our information.
> - There is no way to retrieve information in this system.
There actually is, the information retrieval mechanism that is used to 'express' the DNA (actually, the RNA, an 'unzipped' strand of DNA, but who's counting) is a wonderful little nano machine called a ribosome, it's probably the most amazing structure that I know of outside of the DNA itself.
They're in the volume quoted, the DNA only occupies about 25% of that volume iirc.
> Reliability of hard disks is far, far better than this.
The error correction mechanism that allows your cells to be copied through very large numbers of generations is actually pretty good, most 'mutations' are lethal and only very few actually result in viable copies passing their changes on to newer generations. Mutations are also pretty rare on the whole.
You are right that only TC and AG are valid, but those combinations can be attached 'in reverse' as well (CT / GA) so that makes for four possible combinations in all.
If it weren't for that the movie 'GATTACA' would have been unpronouncable :)
> There actually is, the information retrieval mechanism that is used to 'express' the DNA (actually, the RNA, an 'unzipped' strand of DNA, but who's counting) is a wonderful little nano machine called a ribosome, it's probably the most amazing structure that I know of outside of the DNA itself.
Actually I was going to say that one way to think of using that information is to compute with it, in other words, an organism is simply the result of a computation on its DNA.
There are more ways of having cells arranged, I explicitly mentioned red blood cells because they are exceptional in not containing any DNA, but any chunk of tissue with that volume would do.
> If you use the whole of a cell's DNA to encode information, the cell will die. It can't be used to freely encode information like a hard disk.
Yes, that's obvious, but a cell's DNA does hold that much information, it's just not our information.
> - There is no way to retrieve information in this system.
There actually is, the information retrieval mechanism that is used to 'express' the DNA (actually, the RNA, an 'unzipped' strand of DNA, but who's counting) is a wonderful little nano machine called a ribosome, it's probably the most amazing structure that I know of outside of the DNA itself.
They're in the volume quoted, the DNA only occupies about 25% of that volume iirc.
> Reliability of hard disks is far, far better than this.
The error correction mechanism that allows your cells to be copied through very large numbers of generations is actually pretty good, most 'mutations' are lethal and only very few actually result in viable copies passing their changes on to newer generations. Mutations are also pretty rare on the whole.
You are right that only TC and AG are valid, but those combinations can be attached 'in reverse' as well (CT / GA) so that makes for four possible combinations in all.
If it weren't for that the movie 'GATTACA' would have been unpronouncable :)