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If i may forward a tentative answer? I believe that the reason why ribosomes cannot made RNA strands using protiens as a template is because the ribosome READS RNA but WRITES protiens. Durring the process of translation the RNA is not altered at all. The Ribosome has no means by wich to process the RNA -- either to degrade it or to build it. Thus, the ribosome is not able to synthesize RNA. Now, as to whether in theory you could find/biuld something that would make RNA using DNA as a template -- sure i guess. The information is there -- at least partly. The problem would lie in the fact that ammino acids are redundantly coded for. That is to say that there can be multiple sets of three nulceic acids that can code for a particulare ammino acid. Thus, for a particulare ammino acid, you would not know which set of nucleic acids to use. Wich set of three would be used would be depended on their concentration in surrounding environment. However, the sequence of amino acids DOES matter for the process of transcription (and translation too). Differeing sequences (that code for the same set of amino acids) can have different effects on regulation and expression. This is because these different sequences can intereact diferently with expressors, repressors, ect. Plus they could be more or less likely to form hairpin loops wich are used to regulate their expression (both transcription and translation). SO there, at least, is one problem with the sequence of protein --> RNA. Given multiple acceptable (coding for the same sequences of amino acids) sequences of RNA, you would not be able to specify with one you wanted. Another problem might be that it would be difficult to bring out the introns (the portion of DNA that is not transcripted, but may still have regulatory functions) as well as the promotor region and the stop codon. For these sections are not translated, merely trascripted. So it would be impossible (or at least unlikely, i suppose) to aquire them from protien --> RNA. So there are two objections that i can come up with, at least right now. This is not to say that the protien first hypothesis my not, ultimately, be right. I am just trying to point out what i see as flaws with it. Indeed the fact that protiens and RNA and DNA are intimately connected makes it very difficult to assign one priority. Though i think that the fact that the mechnism for translation is nucleic acid baised, is a strong argument for the priority of nucleic acids. And further, the fact that the ribozyme is RNA based would lead on to suspect that perhaps RNA was the first thing out there. And i do belive that this is what is belived by most biologist to be the case (though i could be wrong on that score). Anyways, GREAT question. It made me think, and i love that. I would say, keep looking into it and wondering about it. Even in it doesn't pan out, the amount you learn by trying to find out, will be well worth the effort! SWEET!

if i might add a bit... There is a small attrative force between the oil and the non-polar chain of the detergent. This is the so-called Van Der Waals force. It is the weakest of the intermolecular forces and is do to instantaneous dipole interactions between the two molecules. That is to say this; even though the molecule is overall-time-avereaged non polar. When two of these molecules get close enough to eachother their electron clouds interact with eachother. This causes small, instantaneous (and short lived) dipoles to form in the molecule. These dipoles are formed in such a manner that they attrach eachother. And so this is the attractive force between the two. However, this force is quite small. The majority of the effect is what is known as the "Hydrophobic effect." Which is what pulkit elluded to ealier. The way to think about this is that there is a large amount of attraction between polar molecules. So much so that they like to crowed together. When they do this, they will force out of their way any molecules that are not equally attracted to them. Thus, these non-polar molecules are essensially squished around until they find an environment in which they are not be shoved out of they way. Such an invironment would be one in which they are surrounded by molecules that have they same attraction for eachother as for our molecule of interest. So, in the case of detergent, the oil is "pushed" out of the polar, aqueous, solution until it finds a non-polar area to reside in, in this case the micelle formed by detergent molecules. IN the end, the "attractive" force that one would suppose cuases the non-polar part of the detergent to gather oils and greese is really do to a "repellent" force of the aqueous phase (really, it is do to the attractive forces of the polar part of the solution, but close enough for government work). Pretty cool, i think. Anyways, everyone else did a great job answering this too, i just thought i would add me two cents, for whatever it is worth (prolly 1/50 of a dollar). Cool

1) If you are not violently ill (ie, pukeing) then i would just say stick it out. As the quarter goes on, you will get more in shape and you will feel less ill. Really, like skye said, it is just a fitness thing. 45 min of running lot of running to just jump into. You will get used to it though. IN the meantime, though, you might make sure that you stretch well before and after running, walk around some after you run (don't just stop, that is really bad, and make sure that you are eating right. The last two are really important. You *really* need to cool down (and warm up too) and if you are eating junk food, then you will really feel it after you excersise, expecially if you are not used to it. So just until you are more used to running for this long, make sure you are eating plenty of fruits and vegitables and not eating candy and fatty foods. But i am not a doctor -- this is just what i have found to help in my life. 2) There is something you might be able to do for this. It most likely is shin splints. One excersise that you can do to help this is a follows. Stand with your back against a wall and the heels of your feel about 6 inches (15 cm) from the wall. Then, simultaniously, raise the front of both your feet as far off the ground as they will go. Ok. Now repeat this AS FAST AS YOU CAN for about a min or so. It will be painfull and it will feel like your shins are going to fall off, but it is quite helpfull. Reapeat this about 5 times or so. So this excersise ever other day, or so, and it will really help with the pain. Again, i am not a doctor, this has just realy helped for me -- if you think the problem is serious, or if it persists then see a physician. Its their job to help you out with this stuff

and what is the answer? (or is it a secret?)

yeah, i know how to pronounce. It was a quote from simpons (actually not a direct quote, but inspired by it) But they actuall question still stands, does anyone have an answer?

seriously though, for all those physics types out there, i was wondering what the nuclear analog to electron promotion is (if such a think exists). I mean, electrons can be promoted up to a new energy level (shell) by exiting them. Is there such a thing for nuclear stuff? Is it just normal vibrational modes, when you are talking about the nucleus? If so, then what about a free proton (no electrons)? Can it be exited to a higher energy state? IF so, is it just the particle in the box thing? Anyways, if anyone feels like answering this question that would be great. I was just wondering this the other day while sitting in lab. Oh, and by the way, if you know of any good reviews about this stuff, i wouldn't mind reading a bit of something on it. Thanks

with you girlwhat??? That is nuts, i done heard of people having realtions with the oposite sex....tell me, how do you get one of those things to talk to you?

dude, british system does make more sense.

mmmm...scones I love scones what i wouldn't give for one million trillion trillion scones

i pretty much always think in pictures words are right out since i can't read or write emotions? Don't have 'em (i am a emeotionally challanged male after all) so that pretty much leaves pictures -- unless you count the magic 8 ball... Oh magic 8 ball, you are never wrong!

ah...too much theory, not enough thought on my part. Yeah. Of course in this sense lots of reactions are not reversible. YOu can always get random side products. WHile in theory, all reactions could be reversed. OK, so for reversible, how about Sodium being added to water. Yeah, i think that is a pretty good one, have to think about it, but i have to grade now, so i will try that one for now

why not?

Burning of Glucose -- or pretty much any hydrocarbon or carbohydrate

denying what occurs. I swear you crazy brits are just making up words now. I was done edumacated in these here uninted stats of america, and i ain't never heard none a' that there evolution.

Now as for the question; I think i will take a stab at it So, as far as sodium acetate goes, we must first consider what is happening. WEll, the sodium acetate is forming a solid and is heating up the sorounding solution, but hte question is, "why?" WEll, that is a supurb question and is excellent for demonstrating the power of thermodymanics (as it can easily be answered with just a basic grasp of enthalpy and entropy and gibbs free energy). So we know that gibbs free energy of a reaction (delta G --> /_\G) is equal to the sum of the enthalpy of that reaction and the negative entropy of a reaction multiplied by the temperature at wich it happens, right? That is, we have; /_\G = /_\H - /_\S (T) ok, we also know that for a process to proceed spontaneously, it must have a negative delta G. Right? Ok, so durring the formation of the solid, the sodium acatate is falling out of solution and forming an ordered lattice (crystals). IN the course of this, the soduim acetate is having it degrees of freedom (spacially) severely diminished (going from free in solution, to trapped in a latice). THis means that in the course of the reaction the system is loosing entropy (becoming more ordered). Ok, so we know that the system is becoming more ordered, right? That must mean that /_\S is negative. But since we subtract out the entropy in the equaion, we see that the overal contribution of the entropy will be a positive number. Well, we know that the reaction does proceed spontaneously (once it is started) becuase when you click the metal disc the pack gets hot. So, /_\ G must be negative. In order for /_\G to be negative, we see that /_\H must be nagative as well (in order to counter-act the positive contribution of the entropy). So we know that /_\H must be negative. Well, what do we call a reaction with a negative /_\H? Exothermic ANd a reaction that is exothermic releases heat. So we have just shown, thermodynamically that the reaction of sodium acetate (or any other substance, for that matter) forming crystals out of solution must be exothermic. It just so happens that for sodium acetate, it is quite exothermic. Now as far as Ammonium Nitrate (A.N.) goes, there is not quite the same elegant explination that will show why it must be endothermic. But lets look at it anyways. OK, so for A.N. what do we have? WE have a solid inside of a container that when it is broken it gets dissoved? (I think that is right). So, using the same reasoning as above, we see that when we are disolving a crystal, we are increaing the entropy of the system. That is becuase the molecules are freed from a constricted latice and put into solution. Now that must mean that entropy is positive (inacreasing). That means that the contribution of entropy to the gibbs free energy will be negative. Right? WEll, if entropy is negative, enthalpy could be positive and the overall gibbs free energy would still be negative. So we see that the reactoin could be negative, though it is not forced to be. Thus, in the case of A.N. it just so happens that the enthalpy of disolving actually is negative. Of course it turns out that all disolving of substances is endothermic, just like all crystalizing is exothermic. But I am not quite sure that you are in a place where i could expalin it (an i am not sure that i have time to write all that right now anyways, sorry) The take home message being that, do to a decrease in entropy durring freezing (crystalization), thermodynamics shows us that crystalization is nessesarily an exothermic reaction. Hope that answers your question -- ask more if you got 'em

I just wanted to clarify something in this statment. Energy is never realeased when a bond in broken. Bonds form becuase they are thermodynamically downhill of the seperate chemicals. Thus, energy is released when bonds form. Becuase enthalpy is a state variable, it follows that enery must be absorbed to break a bond. This means that all bond breaking events are endothermic. It just so happens that right after this endothermic event, an exothermic even occurrs (forming of a new bond). If this new bond is more stable than the old one, then the entire process will be exothermic. Anyways, i just wanted to be clear that breaking of bonds always required energy and, hence, is always endothermic (I know you know this wolfson, but i thought i should make the point extremely clear, so that one learning chemistry would not be confused )

sayo is 100% correct. We will never be free from natural selection -- it just cannot happen. What will happen is that the selective pressures change (as he pointed out). So now instead of selecting for people that can outrun a predator we are selecting for people that can drive well, or people that are resistant to environmental toxins that we introduce, or people that are able to play the corporate game. Natural selectioin is not some self-aware entity that can be "foiled" it is simply a term used to describe how and why gene frequencies tend to favor one type of gene over another.

i have read ender's game too. It is an excellent book. So good in fact, that i think anyone who likes science fiction needs to read it. And as for anyone that doesn't like scifi -- well, i got me hooked Yeah, it was the first scifi book that i read that i actaully liked, before that i was a fantasy junkie. But around my 8th or 9th grade year, my bro handed me this book and was like -- hey check this thing out. SO i did, and now were i am Anyways, enders game rocks! I also really liked Xenocide (but i think i am in a minority there) also by Orson scott card. Other scifi books that i have really, really enjoyed (just in case you are ever looking for more books and you want to trust a stranger for recommendations) are: The moon is a harsh mistress, by Robert Heinlen I have heard it said that this is the most read science fiction book of all time. I would belive it. It is a very well concieved and written book about a penal colony on the moon. A fire upon the deep by Vernor Vinge This book has some of the coolest ideas i have ever read in scifi. However, his writting style does not flow as well as other authors -- which can make him somewhat hard to read. Also this book is slow for the firt 50 pages or so, so you have to be pacient. Yeah, but despite this, it is a great book! If you want a slightly faster, less confusing, easier to read book, check out A deepness in the sky. It is a bit faster paced and, concequntly, a bit easier to read. Unfourtunaltely it does not have all of hte cool ideas of his other book, but that is OK. THis book is still one of the better books i have ever read. Crytonomicon by neil stephenson Not scifi in the classical sense (ie. in space) but rather by definition (it is about sciency stuff, and the book is fiction), this is one of the funniest books i have ever read. But it is still quite serious and a fun journey. Stephenson is a great word-smith who does a good job of inventing characters and sending then on kinda crazy adventures. A great book man! The hitchikers guide to the galaxy by douglas adams. If you have graduated high school and you like dry humor, but you have not read this book (and theo ther four that come after it) stop everything you are doing and read it now! That is all i am going to say about this CHildhoods end and rendezvous with rama[/u] by Arthur C clark WHile not really realated, these are just two of the books that Clark has written that i really enjoyed. Of course if you like how he writes then there are many many more books out there that he has written WEll, i could ramble on and on about books, but you prolly don't want to read about them from a crazy man. SO i will stop. I am sure that there are many more books that i have not mentioned that other will tell you about. I just wrote out a few that popped to the top of my head Cool. ANd happy reading

hmmm...replacing the word with the definition (roughly)....it's just so crazy it might work!

i thought light decayed into two other particles and then recombined to form photons again. And that the permeativity of a substance was a measure of that? Perhaps i am just smoking crack I heard this from a physisist friend on mine. I trust that he was right, when he was telling me this, so if it is wrong i must be remembering incorrectly

ah, sorry. yeah, i think that is othello too...a good game in its own right. yeah, but no worries, yt, people frequently mistake go for othello, when they see it played (prolly cause most people have seen othelo and not seen go) yeah, it is a sweet game though and i would encourage people to check it out.

Not quite. For those that are interested, check out this link. It is a 9 step tutorial about go and how to play it. If you are interested, it is quite easy to learn -- it takes maybe 10-30 min to have a good grasp of the rules. http://www.samarkand.net/Academy/learn_go/overview.html Anyways, it is a really fun game that will challenge you for the reast of your life. MrL. Cool. I am not very good, personally. Prolly around 22-20 kyu or so. What were you playing when you played alot? Perhaps someday we can play together? That would be cool

Ah, i see the source of confusion now First you make the solution and adjust the pH and sterilize it, then you add the element of interest (protiens or DNA or whatever. So the thing you are studying is not in the solution when you are adding NaOH Cool yeah, that makes sense. I am sorry if you thought i was getting furstrated? with you. I was merely trying to add my own thoughts to wolfson's

Care to explain why? I gave a reason why i would filter instead of autoclaving and i said why filtration will work. Now, why would you not filter?? To some extent you are corrret. Of course NaOH is only a stong base -- so the extent to which it damages protiens (denatures then) is only a funtion of its concentration. (Protiens denature at high pH's) So some things to consider are; 1) You will not be adding much base to the solution 2) What you add will be soaked up by the buffer and you will end up with a pH of 7. This pH will not denature protiens. You see, it really only matters what the pH is in solution. there is nothing magical about NaOH, any base will denature protiens, assuming that it can move the pH high enough... Electrophorisis tells us very little stuctural information by itself. It can at best differntiate between coiled, cut, and supercoiled DNA and RNA. WHen it comes to protiens you would be hopelessly lost when it comes to structural information. Electrophorises is really just another size exclution colomn (one that takes charge into account in a limited sense) that is turned on its side. In the end, all that electrophorises really tells you is your charge to mass ratio (and sometimes a very little bit of structural information.