Transcript Cell Respiration II: Fermentation reactions

Cell Respiration II:
Fermentation reactions
During strenuous exercise or when O2 is
unavailable or low in the environment, ATP
production still needs to occur for life to
continue.
Fermentation reactions allow ATP to be
produced and pyruvate (or its derivative)
becomes the terminal electron acceptor
freeing NAD coenzyme to recycle back to
oxidizing (breaking down) food molecules
In fermentation, only 1 pathway
functions  Glycolysis!
• Glycolysis typically produces:
• 2 ATP’s (Net)
• 2 NADH2
• 2 molecules of pyruvate
• Glycolysis does not require O2
• The energy output of glycolysis is marginal as
compared with aerobic respiration
• Pyruvate (or its derivative) serve as the terminal
electron acceptor
In all cases, NAD+ has to
be recycled back to the
system to help oxidize
more food to make ATP!!
Alcohol fermentation
generally occurs in
fungi and bacteria
Lactate fermentation
occurs in many
organisms including
animals