<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><div>On Dec 3, 2010, at 9:38 AM, Dan wrote:</div><div><br></div><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-variant: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "> I don't see anything earth-shattering about this finding.</span></blockquote><br></div><div>While not as earth-shattering as that staple of science fiction, a life form that replaces carbon with silicon, it's still a pretty big deal. Up to now every single living thing ever examined, even viruses, contained phosphorus; not only are phosphate bonds what keeps DNA and RNA from falling apart its also the key part of ATP (<span class="Apple-style-span" style="font-size: 36px; ">Adenosine triPHOSPHATE) a molecule found in all life until now, that is used to store energy. </span></div><div><span class="Apple-style-span" style="font-size: 36px; "><br></span></div><div><span class="Apple-style-span" style="font-size: 36px; ">It's also interesting that 3 elements in the same column of the periodic table, nitrogen phosphorus and now arsenic, can be used by life; it wouldn't surprise me if somebody tried antimony next, or maybe even bismuth, because unlike arsenic or antimony, bismuth is one of the few heavy metals that is not poisonous, its the active ingredient in Pepto-Bismol.</span></div><div><span class="Apple-style-span" style="font-size: 36px; "><br></span></div><div><span class="Apple-style-span" style="font-size: 36px; "> John K Clark </span></div><div><div><div><br></div></div><div><i><br></i></div></div></body></html>