Question

QUESTION 14

1. 445 moles of NADH are produced by the Citric Acid Cycle (CAC). How many moles of glucose needed to be broken down during glycolysis in order to produce enough pyruvate for the CAC to produce this many moles of NADH?

   Note: Brock, a Biology of Microorganisms considers the synthesis of Acetyl-CoA to be part of the Citric Acid Cycle. This is different than what you may have learned in BIOL-151 where the Morris Book considers Acetyl Co-A Synthesis a seperate step. See page 89 of Brock for full details.

   Round your answer to one decimal place.

QUESTION 15

1. If 82 moles of ATP are produced by glycolysis, how many moles of glucose were broken down?

   For every molecule of glucose broken down, 2 molecules of ATP are generated.

QUESTION 16

1. NADH and FADH are produced by the Citric Acid Cycle (CAC) and these electron shuttles go on to the Electron Transport Chain (ETC). A mole of NADH will produce 3 moles of ATP from the ETC. A mole of FADH₂ will produce 2 moles of ATP from the electron transport chain. A single mole of pyruvate will produce 4 moles of NADH and 1 mole of FADH2 from the CAC. Therefore, every  14 moles of ATP came from 1 mole of pyruvate.

   Given:

   The ETC produced 78 moles of ATP from the products of the CAC.

   Find:

   How many moles of pyruvate entered the CAC?

   Note: Brock, a Biology of Microorganisms considers the synthesis of Acetyl CoA from Pyruvate to be part of the Citric Acid Cycle. This is different than what you may have learned in BIOL-151 where the Morris Book considers Acetyl Co-A Synthesis a separate step. See page 89 of Brock for full details.

   Round your answer to one decimal place.

Answer 1

Answer 14: 55.6 moles of glucose.

Explanation: When one mole of glucose is broken down 2 moles of Pyruvic acid are generated; which gets converted to two moles of acetyl CoA and two moles of NADH are generated. Acetyl CoA enters CAC (citric acid cycle); which will generate 6 moles of NADH.

Hence 1 mole of glucose generates 8 moles of NADH through CAC, therefore to generate 445 moles of NADH the moles of glucose needed will be equal to 445/8 that is 55.625 moles of glucose. Rounding off the value it will be 55.6 moles of glucose.

glucose	Pyruvate	Acetyl CoA	NADH
1	2	2	8

Answer 15: 41 moles of glucose

Explanation: If one molecule of glucose gives 2 ATP molecules then to produce 82 moles of ATP by Glycolysis, moles of glucose required will be 82/2 that will be 41 moles of glucose.

Answer 16: 5.6 moles of Pyruvate.

Explanation: A single mole of Pyruvate produces 4 moles of NADH and 1 mole of FADH2;

One mole of NADH is equivalent to 3 moles of ATP after entering ETC therefore 4 moles of NADH gives 3× 4moles of ATP that is 12 moles of ATP.

And one mole of FADH2 is equivalent to 2 moles of ATP after entering ETC.

Hence one Pyruvate gives 14 moles of ATP.

Pyruvate	NADH	FADH2	ATP from NADH = 3× 4=12moles ATP from FADH2 = 2×1=2moles
1	4	1

If 78 moles of ATP are obtained from ETC then the moles of Pyruvate entering the CAC will be equal to 78/14 that is 5.57moles. By rounding off we get 5.6 moles of Pyruvate.

Note: If in question number 15, conversion of Pyruvate to acetyl CoA is not considered as the part of CAC then 6 NADH will be obtained from one glucose molecule and hence to get 445 NADH, 445/6 moles of glucose will be required that is equal to 74.2 moles.

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