On Thu, 16 Nov 2000, Lorenzo wrote:

> It's been a long time since I cared about chemistry but  are
> not the molecular structures quite varied among carbs?

Yes, but polysaccharides are ultimately broken down into
monosaccarides, glucose and fructose, and then used.  A molecule
of glucose from table sugar is not different from a molecule of
glucose from an apple.  Of course, some sugars may be harder to
process if the enzyme for doing so is in short supply, as is
often the case for lactose.  And we have no enzyme at all for
digesting cellulose.  Interestingly, the enzyme for digesting
starch, amylase, is present in human saliva, so that the
digestion of this polysaccharide actually begins in the mouth.  I
wonder why this is so, since as far as I know the sugars cannot
be used in the mouth.

Todd Moody
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