Purchase Solution

Carbon Tracking in TCA Cycle

Not what you're looking for?

Ask Custom Question

C14-Glucose labeled at carbon 5 enters glycolysis, is made into pyruvate, then acetyl CoA, and enters the TCA cycle. How much of the C14 will be released as CO2 during the second turn of the TCA cycle?

Purchase this Solution
Solution Preview

Get out your textbook and look at the structures as I walk you through the process of coming up with the solution.

What happens to the [14C]-Glucose labeled at carbon 5 as it goes through glycolysis?

The important point is that when the six carbon fructose-1,6-bisphosphate splits into DHAP and G3P, and that when DHAP converts into another G3P, that C5 (and C2 for that matter) both end up being the middle carbon in G3P. You can go through the individual steps on your own to confirm this, but it can be easy to remember:

C6 of glucose gets phosphorylated, right?
When it becomes fructose, the same C6 is phosphorylated.
Then, fructose gets phosphorylated on C1 too. Therefore, both ends are phosphorylated, C1 and C6.
When you get to the two G3P molecules, just remember that the carbons with the phosphates on them are the same carbons that ...

Purchase this Solution
Free BrainMass Quizzes
Labor Comfort Measures

Do you know how to comfort someone in labor?

How Well Do You Know Your Body?

This quiz will assess the different systems of the human body. It will examine everything from the organs to the cellular processes that occur.

Breastfeeding Basics

How much do you know about breastfeeding? Find out with this quiz!

Light and Sight Vocabulary

This quiz introduces basic definitions of vocabulary related to light and how human eyes. This information is important for an understanding of sight.

BioChemistry Basics

This Quiz will test your knowledge of the amino acids used in biological systems

View More Free Quizzes
Related BrainMass Solutions

  • TCA Cycle and Glycolysis

    515138 TCA Cycle and Glycolysis Hello, I was hoping someone can explain to me how to follow carbon labels (radioactive 14C) through glycolysis and TCA cycle.

  • Reactions: Inhibit, Catalyse and Glycolosis

    When glycolysis runs faster than the Krebs cycle, citrate (a 6-carbon intermediate in the cycle) builds up and diffuses to the cytosol where it inhibits phosphofructokinase and thus the rate of glycolysis. 2.

  • the steps of glycolysis

    299971 Glycolysis, TCA cycle and the electron transport chain Describe the steps of glycolysis, the TCA cycle, and the electron transport chain including the net yield of ATP from each process Glycolysis is the first step of both aerobic (requiring

  • Concept map on metabolism

    Under aerobic conditions, pyruvate in most cells is further metabolized via the TCA cycle (Krebs cycle).

  • Comparing Rates of CO2 Generation

    They end up being the same carbon in pyruvate.

  • Oxidation of palmitate

    Each cycle of beta-oxidation removes one two-carbon fragments and oxidizes it to acetyl-CoA. In order to prepare the palmitate for beta-oxidation, it needs to be "activated" by condensation with CoA. One ATP is converted to AMP in this reaction.

  • TCA Cycle Function and Reactions

    Is the shunt more or less efficient than the TCA cycle in terms of energy recovery? Show how these reactions can operate as a shunt pathway that allows the TCA cycle to function without alpha-ketoglutarate dehydrogenase and succinate thiokinase."

  • aerobic respiration of glucose

    In the TCA cycle, pyruvate is further oxidized to create reducing equivalents (8 NADH, FADH2), 2 ATP, and CO2. The enzymes involved in the TCA cycle are the same in both plants and animals with only two functional differences.

  • Cyanide's Effects on the Electron Transport System

    Pyruvate then enters the tricarboxylic acid (TCA) cycle, where CO2 is produced. The TCA cycle also generates the reduced cofactors NADH and FADH2.

View More Related Solutions