contestada

In eukaryotes, pyruvate is further metabolized via three main catabolic pathways. Circle the following correct statements
I. Under anaerobic conditions, pyruvate is oxidized leading to the formation of acetyl-CoA and CO2
II. Under aerobic conditions, pyruvate is oxidized leading to the formation of acetyl-CoA and CO2
III. Pyruvate can be reduced to lactate and CO2 during lactic fermentation
IV. Pyruvate can be reduced to ethanol and CO2 during alcoholic fermentation
V. Lactate produced by muscles from pyruvate is converted to glucose in the liver
VI. Lactate produced by the liver from pyruvate is converted to glucose in muscles

Respuesta :

silgoni17

Answer:

II. Under aerobic conditions, pyruvate is oxidized leading to the formation of acetyl-CoA and CO2.

IV. Pyruvate can be reduced to ethanol end CO2 during alcoholic fermentation.

Explanation:

In eukaryotes, pyruvate is an important molecule in energy generation metabolism.

First, under aerobic conditions, cellular respiration takes place in cells. This process starts with a molecule of glucose, that after glycolysis produces pyruvate. After this, and if there is oxygen, pyruvate is oxidized into acetyl-CoA and this reaction frees CO2.

When there is no oxygen available, anaerobic fermentation takes place. There are two types of fermentation: lactic fermentation and alcoholic fermentation.  

Lactic fermentation goes in muscle cells in eukaryotes. This process occurs after pyruvate is produced and there is not O2.  In lactic fermentation, pyruvate is reduced to lactate (or lactic acid), but not CO2, so option III is wrong.

Alcoholic fermentation is carried by some yeast, and it also takes places in absense of oxygen. After glycolysis, when pyruvate is formed, this molecule is metabolized into acetaldehyde and CO2 is freed. Moving forward, acetaldehyde is reduced by NADH+H+, producing ethanol and NAD+.

Otras preguntas