Portage Learning Chem 210 - Module 7 Problem Set

Portage Learning Chem 210 - Module 7 Problem Set A scientist uses the term flux regarding a biochemical pathway. What does flux mean? Flux is the rate of flow through a biochemical pathway. A particular pathway breaks down proteins into amino acids. Is this an anabolic or a catabolic pathway? Catabolic. This is degradation of a molecule. The acetyl group is connected to CoA to make Acetyl-CoA. A) What specific atom of CoA connects to the carbon atom on the acetyl group? B) What nucleotide base is part of CoA? A) Sulfur B) Adenine Both carbohydrates and lipids are broken down into Acetyl-CoA for further processing. What pathway does Acetyl-CoA go to next? Citric Acid Cycle (CAC) What is the “ETC” and what happens there? Electron transport chain. NADH is converted into ATP at the ETC. What is the sign (+ or -) of ΔG for the breakdown of ATP to ADP? Why is the sign important? (-). A negative means spontaneous, or favorable, and is able to power other processes. What molecule (FADH2, ATP, ADP, or CoA) is shown below? ADP What are the two phases of glycolysis? How many reactions in each? The preparatory phase and payoff phase. Five reactions in each. How many ATPs are invested in glycolysis? 2 What is the net number of ATP gained from glycolysis? 2 (2 invested, 4 gained, for a net of 2) How many reactions of glycolysis have a single arrow “→” in their reaction equation? 3 What is the fate of pyruvate produced in glycolysis? Under anaerobic conditions, it goes to lactate or sometimes ethanol or other products to regenerate NAD+ for glycolysis. Under aerobic conditions, it proceeds to the citric acid cycle. For one molecule of glyceraldehyde-3-phosphate, how many ATP or NADH are produced (or required) in the glyceraldehyde-3-phosphate to 1,3-bisphosphoglycerate step in glycolysis? 1 NADH required 1 NADH produced 2 ATP produced 1 ATP required None of the above Fill in the appropriate blanks in the following sentence using the word bank. All words will not be used; words can be used more than once. Word (phrase) bank: Reaction 3 Reaction 6 Reaction 7 Reaction 10 Fructose-6-phosphate 1,3-bisphosphoglycerate Glyceraldehyde-3-phosphate Pyruvate In (A) , phosphate from (B) is transferred to ADP and yields ATP. In (C) , phosphate from ATP is transferred to (D) forming ADP . A) reaction 7 B) 1,3-bisphosphoglycerate C) Reaction 3 D) Fructose-6-phosphate How many steps are found in the CAC? 8 How much ATP is produced per NADH molecule after oxidative phosphorylation? Per FADH2? NADH- 2.5 per molecule. FADH2 – 1.5 per molecule How many CO2 are lost per each turn of the CAC? 2 molecules of CO2 are lost. How many of the steps in the CAC are equilibrium reactions? 5 reactions have equilibrium arrows. What reaction is catalyzed by the PDH? pyruvate to acetyl-CoA Given the diagram of the citric acid cycle, answer the following questions. Given the diagram of the citric acid cycle, answer the following questions. A. (1 pt) What compound is the five-carbon molecule? (contains 5 carbons) B. (2pt) Identify the four-carbon compounds. C. (1 pt) How many GTP molecules are produced per turn of this cycle? D. (1 pt) What is one reaction that is an equilibrium reaction? (give reaction number) A. a-ketoglutarate B. Succinate, fumarate, malate, and oxaloacetate C. 1 GTP D. Any one of 2, 5, 6, 7, and 8 The β-oxidation pathway is the degradation pathway for fatty acids. A. Where, in the cell, does the β-oxidation pathway occur? B. How many steps are in the β-oxidation pathway? A. In the mitochondria. B. Four reaction steps. How many FADH2 and NADH molecules are produced per round of β-oxidation? One of each FADH2 and NADH. Which number on the molecule below indicates the α and β carbons? Carbon 2 is the alpha, and Carbon 3 is the beta. Can β-oxidation occur with odd-numbered fatty acids? Can β-oxidation occur with fatty chains containing double bonds? Explain your answer in at least three complete sentences. Yes to both types of chains. The β-oxidation process occurs with both unsaturated fatty acids (those with double bonds) and fatty acids that have an odd number of carbons. Double bonds and odd-numbered chains each present a structural problem for the standard enzymes of the pathway. So, there are additional steps with enzymes for each type of molecule, but the molecules are degraded with energy recovered.