What accepts the electrons from NADH during fermentation in humans ?

Question

a) O2

b) NAD+

c) CO2

d) pyruvic acid

e) NADP

Answer 1

d) pyruvic acid

From http://en.wikipedia.org/wiki/Fermentatio...

"Fermentation is the process of deriving energy from the oxidation of organic compounds, such as carbohydrates, using an endogenous electron acceptor, which is usually an organic compound. This is in contrast to cellular respiration, where electrons are donated to an exogenous electron acceptor, such as oxygen, via an electron transport chain

"In humans, for example, lactic acid fermentation provides energy for a period ranging from 30 seconds to 2 minutes. The final step of fermentation, the CONVERSION OF PYRUVATE to fermentation end-products, does not produce energy. However, it is critical for an anaerobic cell, since it REGENERATES NICOTINAMIDE ADENINE DINUCLEOTIDE (NAD+), which is required for glycolysis. This is important for normal cellular function, as glycolysis is a primary source of ATP production in anaerobic conditions."