Choose th correct combination of labelling the molecules involved in the pathway of anaerobic respiratioin in yeast

Options

A. A – Ethanol B – `CO_2` C –Acetaldehyde
B. A – `CO_2` B – Ethanol C –Acetaldehyde
C. A – `CO_2` B – Acetaldehyde C – Ethanol
D. A – Ethanol B – Acetaldehyde C – `CO_2`

Answer

D

Explanation

Alcohol Fermentation: In fermentation by yeast incomplete oxidation of glucose is achieved under the anaerobic condition where pyruvic acid is converted to `CO_2` an ethanol.
In the first step pyruvic acid is decarboxylated resulting in the formation of acetaldehyde and `CO_2`
`underset("(Pyruvic acid)")(2CH_3COCOOH)underset("decarboxylate")overset("Pyruvic acid")rarr underset("(Acetaldehyde)")(2CH_3CHO+2CO_2)`
In the second step, acetaldehyde is reduced to the alcohol by `2NADH+ H^(+)`
`2CH_(3)CHO+2NADH + 2H^(+)overset("Alcohol")underset("dehydrogenate") rarr2C_(2) H_5 OH + 2NAD^(+)`