Download Alcoholic fermentation

ANAEROBIC RESPIRATION
Complete the notes sheets below. Where you see a blank (…………………..), decide
which word/phrase is most appropriate.
………………………. (which takes place in the ……………………) produces …… molecules of pyruvate.
The fate of the pyruvate depends on …………………… availability. In the absence of oxygen,
alcoholic fermentation or lactic fermentation takes place.
2 x PYRUVATE (….C)
1. Alcoholic fermentation:
When there is insufficient …………………….., it is important that the reduced NAD (……………) is
…………………….. back to NAD+ so that the energy yielding phase of glycolysis can continue.
In yeast, pyruvate is decarboxylated to ETHANAL (…..C), releasing …………….. . The enzyme
alcohol dehydrogenase then ……………….. ETHANAL to ETHANOL (…..C), at the same time
………………… NADH back to ……………. .
CH3CHO + NADH

C2H5OH +NAD+
Alcohol dehydrogenase
The process is summarised below:
NADH
NAD+
Alcohol dehydrogenase
C2H5OH + CO2
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What is the net production of ATP per molecule of glucose in anaerobic respiration using
alcoholic fermentation? …………… ATP molecules
2. Lactic fermentation:
The
main
aim
of
lactic
fermentation
is
to
…………………………………………………………………………………………………………………………………………………
……………………………………………………………………………………………………………
Pyruvate is …………………… by NADH to form ………………………… acid. As this is a redox reaction,
NADH is ………………………… back to ……………. since an …… atom is donated to the pyruvate. This
reaction is catalysed by lactate dehydrogenase.
 1 molecule of NADH is ………………….. per pyruvate molecule.
 1 molecule of glucose will produce ………… molecules of ATP in using this form of
…………………………… respiration.
The process is summarised below:
NADH
NAD+
Lactate dehydrogenase
C3H6O
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