I don't recall seeing this number in standard texts -- I calculated it
while figuring out energy conversion problems for my own class
in comparative animal physiology at the University of Michigan-
Dearborn.
It works out in two ways: The electron transport chain has a voltage
drop, from NADH to H2O of about 1 volt. (52 kcal for 1 mole of
electron pairs, or about 100,000 joule per mole of electrons and
one mole of electrons is F = 100,000 coulombs). Then, with a
human metabolic rate near 100 W, since most of the energy is
derived from aerobic metabolism, there must be 100 amps of
current running through the electron transport chain.
The second methd is more direct. A metabolic rate of, say 2400
kcal/day uses about 3.5 moles of glucose (at 686 kcal/mole). Of
course we don't just metabolize glucose, but this is a rough
calculation. At 38 ATP/glucose, this produces about 133 moles
of ATP/day. Since one electron pair yields 3 ATP, this represents
about 89 moles of electrons/day (also ignoring the few ATP not
made through the electron transport system). This is 8,900,000
coulombs/day, or 100 amps.
Incidentally, I use Eckert's "Animal Physiology" for comparative and
Delcomyn's "Foundations of Neurobiology" for neuro, both upper division
undergrad courses. Do you have anything better?
Richard Hall wrote in message ...
>I love these interesting tidbits and would like to know the original
source
>or at least how the figure of 100 amperes was calculated and the
>assumptions made. Our electron transport systems generate 100 amps
current
>in producing the 2-4,000 Kcal of "our daily ATP"? Please elaborate.
>>rlh
>>At 10:06 PM -0500 1/20/99, Richard Norman wrote:
>>In all cells that metabolize aerobically (i.e., most all except red
>blood cells)
>the mitochondria have an electron transport system that constantly pump
>a totality of some 100 amperes of current (totalled over all the cells
>of
>the body). This tends to be "DC", and the mitochondria are arranged
>in a random fashion so any fields will cancel out. I have never heard
>of
>any physical phenomena associated with this type of electrical current.
>Richard Hall
>Comparative Animal Physiologist
>Division of Sciences and Mathematics
>University of the Virgin Islands
>St. Thomas, USVI 00802
>>809-693-1386
>rhall at uvi.edu
