From: Monya Baker (mbaker@acumenjournal.com)
Date: Fri Oct 17 2003 - 09:25:01 PDT
Subject: Re: catalysts Date: Fri, 17 Oct 2003 09:25:01 -0700 Message-ID: <5BD29DF347AC0844ADBAD30BC00DBA31B905FD@sfo-mail1.acumen.com> From: "Monya Baker" <mbaker@acumenjournal.com>
Hi Geoff,
You're right. Enzymes are around in such small concentrations and so
have no ability to sequester reactants. So if there was a way for a
reaction to happen faster, it would.
The other teacher is probably thinking that reaction in our bodies that
extract energy from food are slower and more efficient than the
reactions in directly burn the food (i.e. converting the carbon
containing molecules directly to water and carbon dioxide in flames is
faster than diverting it through glycolysis and the Krebs cycle and the
electron transport chain in cells).
Each individual enzyme-aided reaction happens faster than it would
without the catalyst. You could avoid all the complicated carbon
shuffling and burn sugar faster with fire; the initial flame supplies
activation energy for reactions that release energy that activates other
reactions. But even if the final chemical equation is the same
(carbon-based molecules going to water and carbon dioxide) the routes
are completely different and can't be compared the same way.
The idea of a catalyst raising the activation energy is just plain
wrong.
________________________
Monya Baker
Science Writer
Acumen Journal
direct 415.633.7973
fax 415.633.7901
One Montgomery Street, Suite 3700
San Francisco, CA 94104
This archive was generated by hypermail 2.1.3 : Mon Aug 02 2004 - 12:05:31 PDT