Question

What condition is required for fermentation to occur? A. When the energy production cycle ends of the Krebs cycle B. When oxygen levels within a cell are too low for aerobic respiration C. When 20 molecules of ATP are needed D. When a glucose molecule needs to break down completely

Answer 1

The answer is B.

Fermentation(an anaerobic process) is a way of harvesting chemical energy without using either oxygen or any electron transport chain.

Fermentation consists of glycolysis plus reaction that regenerate NAD+ by transferring electrons from NADH to pyruvate or derivatives of pyruvate.

There are many types of fermentation, lactic acid fermentation and alcohol fermentation are the most common two.

Answer 2

The condition required for fermentation to occur is when the oxygen levels within a cell are too low for aerobic respiration.

Further Explanation:

Cellular respiration

• This is the process by which food substances such as glucose are broken down to yield energy in the form of ATP for the cells. The energy is then sued to drive cellular activities such as transport and cell division.
• Cellular respiration is classified into two;

Aerobic respiration.

• Aerobic respiration is a type of respiration that takes place in living organisms in the presence of oxygen gas.
• The process involves the breakdown of organic compounds such as glucose to yield energy in the form of ATP and carbon dioxide together with water as byproducts.

Anaerobic respiration/Fermentation

• Anaerobic respiration on the other hand is a type of respiration that occurs in absence of oxygen gas or in presence of low levels of oxygen gas in the cells.
• It involves the breakdown of organic compounds to form small amount of energy in the form of ATP and ethanol or lactic acid as byproducts.

Occurrence.

Aerobic respiration occurs in three stages;

• Glycolysis: This is the first stage of aerobic respiration where an organic molecule such as glucose is broken down to form 2 molecules of Acetyl-CoA and net production of 2 ATP molecules. Each glucose molecule yields two molecules of ATP and two molecules of Acetyl-CoA.

• Kerb's cycle: It is the second phase of aerobic respiration that involves a series of reactions catalyzed by various enzymes. Acetyl-CoA from glycolysis undergoes a series of reaction to produce six molecules of NADH, two molecules of FADH2, together with carbon dioxide and two molecules of ATP.

• Electron transport chain; This is the final stage of Aerobic respiration, where the six molecules of NADH and two molecules of FADH from Kreb's cycle are used to generate energy in form of ATP. This stage generates 34 molecules of ATP.

Anaerobic respiration/Fermentation occurs in two stages;

• Glycolysis; One glucose molecule is broken down to pyruvate and two molecules of ATP are formed.

• Fermentation; This is the second stage of anaerobic respiration, pyruvate from glycolysis can undergo various steps depending on the living organism. It can be converted to ethanol or lactic acid together with carbon dioxide.

Keywords: aerobic respiration, anaerobic respiration, Glycolysis, kreb's cycle, Fermentation and Electron transport.

Learn more about:

• Cellular respiration: brainly.com/question/1544781
• Fermentation: brainly.com/question/1544781
• Aerobic respiration: brainly.com/question/1544781
• Glycolysis; brainly.com/question/1544781
• Kreb's cycle; brainly.com/question/1544781

Level: High school

Subject: Biology

Topic:  Cellular Respiration

Sub topic: Aerobic and anaerobic respiration