What are the important metabolites/cofactors and where do they come from/how do they enter the citric acid cycle? • How is free energy transferred both two and from? • What are the important enzymes? • Where are the major regulatory steps and how are they regulated? • Why is it a cycle?.

In this chapter you learned that cellular respiration is a lengthy metabolic pathway that consists of 4 distinct phases, beginning with glucose and ending with 36 ATP molecules. The diagram below illustrates how certain compounds from the breakdown of all nutrients (proteins, carbohydrates, and fats) can be converted into intermediates in głycolysis and the Kreb's Cycle and how they can enter and leave at many different stages of these pathways. Use the lettered items below to corredly identify the numbered items (106 to 115) in the diagram. Record your responses onto the Google Form. food stage 1: a. proteins breakdown of large macro- molecules to simple subunits 106 107 108 b. co2 109 110 fatty acids and glycerol с. lipids stage 2: 111 breakdown of simple subunits to acetyl CoA accompanied by production of limited ATP and NADH d. Kreb Cycle pyruvate simple sugars g. glucose 112 f. ATP 113 02 g. stage 3: complete oxida tion of acetyl COA to H0 and coz involves production of much NADH,…

@ O € O (2) If acetyl-CoA were labeled with ¹4C at carbonyl group, and then were used as the substrate for the citric acid cycle. Which of the following intermediates would be produced during the first round of the cycle contains the label at the correct position? OH H I 1 0₂C-C-C-CH₂-CO2 | I H CO, OH H `O,C-C–C–CH,-CO, I I H CO, OH H | | `O,C-C–C–CH, CO I I H CO2 OH H T O,C-*C-C-CH2-CO2 I H CO, OH H 0₂C-C-C-CH₂-CO2 I I H CO,

Concerning the citric acid cycle (TCA cycle), which of the following statements is false? a. Substrate level phosphorylation in the TCA cycle produces 2 GTP per the oxidation of a single glucose molecule b. The TCA cycle generates electron carriers c. Oxidation of pyruvate in the matrix of the mitochondria produces sixteen total electrons  d. The fate of the carbonyl carbon of acetyl CoAin the TCA cycle is to be lost as CO2 in the second turn e. Radiolabeling of the methyl carbon of pyruvate in the TCA cycle shows the carbon signal to split through successive turns