Glycolysis & Fermentation

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9 questions

Glycolysis is a pathway in which one 6-carbon molecule of glucose is oxidized to produce two 3-carbon molecules of pyruvic acid. The pathway can be condensed into the following four main steps.
Step 1. Two phosphate groups are attached to one molecule of glucose, forming a new 6-carbon compound. The phosphate groups are supplied by two molecules of ATP, which are converted into two molecules of ADP in the process.
Step 2. The 6-carbon compound formed in step 1 is split into two 3-carbon molecules of glyceraldehyde 3 = phosphate (G3P).
Step 3. The two G3P molecules are oxidized, and each receives a phosphate group. The product of this step is two molecules of a new 3-carbon compound. The oxidation of G3P is accompanied by the reduction of two molecules of NAD+ to NADH. Like NADP+, NAD+ is an organic molecule that accepts electrons during redox reactions.
Step 4. The phosphate groups added in step 1 and step 3 are removed from the 3-carbon compounds formed in step 3. This reaction produces two molecules of pyruvic acid. Each phosphate group is combined with a molecule of ADP to make a molecule of ATP. Because a total of four phosphate groups were added in step 1 and step 3, four molecules of ATP are produced.

Fermentation is the process in which NAD+ is regenerated, allowing cells to maintain glycolysis in the absence of oxygen. Fermentation occurs in the cytoplasm of cells. There are 2 types of fermentation; Lactic Acid Fermentation and Alcohol Fermentation. 

Lactic Acid Fermentation: Enzymes convert pyruvate that's made during glycolysis to lactic acid. 
Alcohol Fermentation: Occurs in yeast and some bacteria. Pyruvate is converted to ethyl alcohol and carbon dioxide. NADH donates electrons during this reaction. NAD+ is regenerated. 

What is the final product of glycolysis?

NADP+ and NAD+ are similar in that both...

Yeast use this process to convert pyruvic acid to ethyl alcohol and CO2: __________

3-Carbon product of glycolysis: __________

Process that produces large amounts of ATP: __________

Does not require oxygen: __________

The process in which cells make ATP by breaking down organic compounds: __________

Electron carrier molecule similar to NAD+:__________

The recycling of NAD+ under anaerobic conditions: __________