Question

5. What molecule is essential to regenerate at the end of the Krebs cycle to start the process again?

Answer 1

Answer: Oxaloacetate

Explanation: The krebs cycle starts with the pyruvic acid that is obtained after glycolysis. The Kreb's cycle begins when the Acetyl coA combines with a four molecule oxaloacetate.

The main product formed is citric acid thats why the cycle is also called as citric acid cycle. After the citric acid is formed it goes through a series of reactions to form NADH, FADH2 and ATP.

The carbon dioxide is also released during this process. The oxaloacetate formed is used to start the cycle so its is regenerated again and again.

Answer 2

Oxaloacetate is the molecule that is essential to regenerate at the end of the Kreb's cycle to start the process again.

Further Explanation;

Cellular respiration;

• Cellular respiration is the process by which living organisms use nutrients or food substances to generate energy in the form of ATP that is required to drive cellular processes.
• Cellular respiration takes place in three stages; glycolysis, Kreb's cycle and electron transport.

Glycolysis

• It 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.
• During the process of glycolysis 2 molecules of energy carrier, NADH which are then taken to energy transport chain to produce more ATP.

Kreb'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.
• During Kreb's cycle Acetyl-CoA is converted to Citrate to Isocitrate to alpha-ketoglutarate to Succinyl-CoA to Succinate to Fumarate to malate and lastly to Oxaloacetate.
• Oxaloacetate is the final molecule formed during the TCA cycle and is essential to enhance the start of Kreb's cycle once more.

Electron transport chain

• It is the final stage of Aerobic respiration, where the six molecules of NADH and two molecules of FADH2 from Kreb's cycle and 2 NADH molecules from glycolysis are used to generate more energy in the form of ATP.
• This stage generates 34 molecules of ATP.  
• Keywords: Cellular respiration, energy carriers, energy in the form of ATP, use of energy carriers from glycolysis and citric acid cycle to generate more ATP.

Learn more about:

• Cellular respiration: brainly.com/question/9413077
• Stages of cellular respiration: brainly.com/question/9413077
• Kreb's cycle: brainly.com/question/9413077
• Electron transport chain: brainly.com/question/9413077

Level: High school

Subject: Biology

Topic: Cellular respiration

Sub-topic: Kreb's cycle