Thursday, November 13, 2008
Feline thoughts travel far
We have recently acquired a new neighbour in the form of a very friendly marmalade cat with a runny nose. He takes a great interest in all our outdoor doings, our being careful not to let him in on our indoor doings. He especially likes sitting on one. However, the other day I managed to shut him in the shed for an hour or so and he bounded out at great speed on release.
At which point I get to wondering what would happen if it had been a few days rather than a few hours. Later on, I learn that cats very rarely die of thirst as they are able to lift water from almost any kind of damp patch - of which there are plenty in our garage. Maybe they have some special glue on their tongues, or some special nano-holes to which the water molecules can adhere.
Still later, was talking about this in TB where I am moved to observe that we share 99% of our genes with cats. Pondering still harder and seeking to make an impression, that we share 80% of our genes with potatoes.
Much later, on the way home, it occurs to me that I have no idea what a gene is and what it means to say that one individual shares so many genes with another, or that one species shares so many genes with another. Sent speedily to sleep on this knotty problem.
On waking, I consult the weighty tome which I bought with some of my leaving money from HMT. After some effort - brain needs to be a bit younger for this sort of thing - I learn that a gene corresponds roughly to a chunk of DNA. That DNA is made up of what might be called bits, each of which takes one of four values. A sequence of three bits defines an amino acid and a sequence of amino acids defines a protein. There is the question of where to start: starting at bit 5078 gives a quite differant protein than starting at bit 5079. There is then the question of headers and trailers. Of the areas of padding of which DNA seems to be full. Of control area.
Put simply, a gene is a chunk of DNA which defines a protein and, going further, enables the containing cell to manufacture that protein. This will only happen, in general, if the gene has been switched on by some other protein binding to the right place in the control area. So we have what amounts to a computer with a rather strange instruction set. Which makes it much more complicated than a proper computer, perhaps in the same sort of way the go, with its very simple rules, is much more complicated than chess. It would be good, if one had more time, to join the many people who must be writing models of this sort of thing on real computers.
But while this was an interesting diversion, I have still not answered the start question. Maybe the original 80% statement means no more than that a potato has the genetic code to synthesise 80% of the proteins than a human can. Without saying anything about how alike human and potatoes look. Do they have the same number of legs sort of thing. To be continued...
Back in the kitchen, circumstances conspired to force me to buy bread at Mr S for once in a while. Taste the differance bloomer. Sold in a plastic bag, into which, to be fair, it had not been long put. Not too bad but not really the real thing. They are trying but I think the answer must lie in using improper flour and in being in too much of a hurry. Nowhere near as good as Cheam on a good day. But possibly more reliable. Less subject to human errors of the sort which result from the sole apprentice having been on a bender and not getting to work until 0400.
At which point I get to wondering what would happen if it had been a few days rather than a few hours. Later on, I learn that cats very rarely die of thirst as they are able to lift water from almost any kind of damp patch - of which there are plenty in our garage. Maybe they have some special glue on their tongues, or some special nano-holes to which the water molecules can adhere.
Still later, was talking about this in TB where I am moved to observe that we share 99% of our genes with cats. Pondering still harder and seeking to make an impression, that we share 80% of our genes with potatoes.
Much later, on the way home, it occurs to me that I have no idea what a gene is and what it means to say that one individual shares so many genes with another, or that one species shares so many genes with another. Sent speedily to sleep on this knotty problem.
On waking, I consult the weighty tome which I bought with some of my leaving money from HMT. After some effort - brain needs to be a bit younger for this sort of thing - I learn that a gene corresponds roughly to a chunk of DNA. That DNA is made up of what might be called bits, each of which takes one of four values. A sequence of three bits defines an amino acid and a sequence of amino acids defines a protein. There is the question of where to start: starting at bit 5078 gives a quite differant protein than starting at bit 5079. There is then the question of headers and trailers. Of the areas of padding of which DNA seems to be full. Of control area.
Put simply, a gene is a chunk of DNA which defines a protein and, going further, enables the containing cell to manufacture that protein. This will only happen, in general, if the gene has been switched on by some other protein binding to the right place in the control area. So we have what amounts to a computer with a rather strange instruction set. Which makes it much more complicated than a proper computer, perhaps in the same sort of way the go, with its very simple rules, is much more complicated than chess. It would be good, if one had more time, to join the many people who must be writing models of this sort of thing on real computers.
But while this was an interesting diversion, I have still not answered the start question. Maybe the original 80% statement means no more than that a potato has the genetic code to synthesise 80% of the proteins than a human can. Without saying anything about how alike human and potatoes look. Do they have the same number of legs sort of thing. To be continued...
Back in the kitchen, circumstances conspired to force me to buy bread at Mr S for once in a while. Taste the differance bloomer. Sold in a plastic bag, into which, to be fair, it had not been long put. Not too bad but not really the real thing. They are trying but I think the answer must lie in using improper flour and in being in too much of a hurry. Nowhere near as good as Cheam on a good day. But possibly more reliable. Less subject to human errors of the sort which result from the sole apprentice having been on a bender and not getting to work until 0400.
# posted by Jim @ 3:04 AM 
