1. Cellular Respiration
Honors Biology

21. http://www.science.smith.edu/departments/Biology/Bio231/etc.html

23. http://www.youtube.com/watch?v=3y1dO4nNaKY

31. Photosynthesis

53. Bacteriorhodopsin

56. “Tragedy of the gifted rugby player, 18, who
died after buying deadly 'fat-burning' pills
online,” the Daily Mail reports. It is just of
one of many newspapers and websites who
have reported on the death of Chris
Mapletoft, who died after taking 2,4Dinitrophenol (DNP). This is a banned
substance that has been marketed on the
internet as a "wonder slimming aid".
DNP has also been linked with the deaths of
students Sarmad Alladin and Sarah Houston
earlier in 2013.
http://www.youtube.com/watch?v=BBVnM9T5er8

57. • 2,4-Dinitrophenol (2,4-DNP, or simply
DNP), C6H4N2O5, is an inhibitor of efficient
energy (ATP) production in cells with
mitochondria.
• Consider potential targets.

58. •
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Warning signs of DNP poisoning
Warning signs include:
hot dry skin
excessive thirst
excessive sweating
abnormally fast heartbeat
rapid breathing
In 1933, an American researcher discovered that when taken by
humans, DNP dramatically speeds up the metabolism leading to
rapid weight loss. It was subsequently marketed as a weight loss
drug. It was quickly withdrawn from the market, however, after it was
found to be highly toxic, causing significant side effects and in some
cases, deaths.
In 1938 the American Food and Drug Agency issued a statement
saying DNP was “extremely dangerous and not fit for human
consumption”.
It appears that DNP has becoming increasing popular during the
last decade among bodybuilders for its "quick-fix" ability to lead to
rapid weight loss. Presumably this information was spread both by

59. • It uncouples oxidative phosphorylation by
carrying protons across the mitochondrial
membrane, leading to a rapid
consumption of energy without generation
of ATP.
• Given your understanding of oxidative
phosphorylation, how do you think this
would drive weight loss?

60. • Pharmacological action
• In living cells, DNP acts as a proton
ionophore, an agent that can shuttle
protons (hydrogen cations) across
biological membranes.
• Consider significance.

61. Mechanism:
•DNP uncouples oxidative phosphorylation by
carrying protons across the mitochondrial
membrane, leading to a rapid consumption of energy
without generation of ATP.
•It defeats the proton gradient across mitochondria
and chloroplast membranes, collapsing the proton
motive force that the cell uses to produce most of its
ATP chemical energy. Instead of producing ATP, the
energy of the proton gradient is lost as heat.