CHEM210 / CHEM 210 Module 7 Exam | Latest 2026–2027 Update | Organic Chemistry | Portage Learning | Verified Questions & Answers | Grade A

CHEM210 / CHEM 210 Module 7 Exam | Latest 2026–2027 Update | Organic Chemistry | Portage Learning | Verified Questions & Answers | Grade A Q: A scientist uses the term flux regarding a biochemical pathway. What does flux mean? Answer Flux is the rate of flow through a biochemical pathway. Q: A particular pathway breaks down proteins into amino acids. Is this an anabolic or a catabolic pathway? Answer Catabolic. This is degradation of a molecule. Q: 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? Answer A) Sulfur B) Adenine Q: Both carbohydrates and lipids are broken down into Acetyl-CoA for further processing. What pathway does Acetyl-CoA go to next? Answer Citric Acid Cycle (CAC) Q: What is the "ETC" and what happens there? Answer Electron transport chain. NADH is converted into ATP at the ETC. Q: What is the sign (+ or -) of ΔG for the breakdown of ATP to ADP? Why is the sign important? Answer (-). A negative means spontaneous, or favorable, and is able to power other processes. Q: What molecule (FADH2, ATP, ADP, or CoA) is shown below? Answer ADP Q: What are the two phases of glycolysis? How many reactions in each? Answer The preparatory and payoff phase. Five reactions in each. Q: How many ATPs are invested in glycolysis? Answer 2 Q: What is the net number of ATP gained from glycolysis? Answer 2 (2 invested, 4 gained, for a net of 2) Q: How many reactions of glycolysis have a single arrow "→" in their reaction equation? Answer 3 Q: What is the fate of pyruvate produced in glycolysis? Answer 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. Q: 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? Answer 1 NADH produced Q: 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: Answer Reaction 3 Reaction 6 Reaction 7 Reaction 10 Fructose-6-phosphate 1,3-bisphosphoglycerate Glyceraldehyde-3-phosphate Answer Pyruvate Q: In ____(A)_____, phosphate from _____(B)_______ is transferred to ADP and Answer yields ATP. Q: In ___(C)____, phosphate from ATP is transferred to ____(D)_______ forming ADP . Answer A) Reaction 7 B) 1,3-bisphosphoglycerate C) Reaction 3 D) Fructose-6-phosphate Q: How many steps are found in the CAC? Answer 8 Q: How much ATP is produced per NADH molecule after oxidative phosphorylation? Per FADH2? Answer NADH- 2.5 per molecule. FADH2 - 1.5 per molecule Q: How many CO2 are lost per each turn of the CAC? Answer 2 Q: How many of the steps in the CAC are equilibrium reactions? Answer 5 reactions have equilibrium arrows. Q: What reaction is catalyzed by the PDH? Answer Pyruvate to acetyl-CoA Q: 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) Answer A) alpha-ketoglutarate B) Succinate, fumarate, malate, and oxaloacetate C) 1 GTP D) Any one of 2, 5, 6, 7, and 8 Q: The beta-oxidation pathway is the degradation pathway for fatty acids. A. Where, in the cell, does the beta-oxidation pathway occur? B. How many steps are in the beta-oxidation pathway? Answer A) In the mitochondria B) Four reaction steps Q: How many FADH2 and NADH molecules are produced per round of beta oxidation? Answer One of each FADH2 and NADH. Q: Which number on the molecule below indicates the alpha- and beta-carbons? Answer Carbon 2 is the alpha, and Carbon 3 is the beta. Q: Can beta-oxidation occur with odd-numbered fatty acids? Can beta-oxidation occur with fatty chains containing double bonds? Explain your answer in at least three complete sentences. Answer Yes, to both types of chains. The beta-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. Q: True or False: The ΔG value for a particular reaction is -78kJ/mol. This value indicates the reaction is spontaneous. Answer true Q: True or False: A biochemical metabolic pathway is a single reaction that converts starting material into products. Answer false Q: True or False: A biochemical metabolic pathway is a series reaction that converts starting material into products. Answer true Q: True or False: Three ATP molecules are used in the energy-investing stage of glycolysis. Answer false Q: True or False: The citric acid cycle occurs in the presence of oxygen. Answer true Q: True or False: The citric acid cycle occurs in the absence of oxygen. Answer false Q: True or False: The β-oxidation pathway only degrades odd-numbered fatty acids. Answer true Q: In total, how many ATP and/or NADH are produced in the glucose to pyruvate steps in glycolysis? Answer 2 ATP and 2 NADPH produced Q: In converting glucose to pyruvate, how many ATP or NADH are produced (or required) in the fructose-6-phosphate to fructose-1,6-bisphosphate step in glycolysis? Answer 1 ATP required Q: In converting glucose to pyruvate, how many ATP or NADH are produced (or required) in the glucose to glucose-6-phosphate step in glycolysis? Answer 1 ATP required Q: In converting glucose to pyruvate, how many ATP or NADH are produced (or required) in the Answer glyceraldehyde 3-phosephate to 1,3-bisphosphoglycerate step in glycolysis? 2 NADH produced Q: In converting glucose to pyruvate, how many ATP or NADH are produced (or required) in the Answer 1,3-bisphosphoglycerate to 3-phosphoglycerate step in glycolysis? 2 ATP produced Q: In converting glucose to pyruvate, how many ATP or NADH are produced (or required) in the Answer phosphoenolpyruvate to pyruvate step in glycolysis? 2 ATP produced What is the primary product of glycolysis? Answer pyruvate In glycolysis, when glucose enters a cell, it is immediately phosphorylated to form glucose-6-phosphate. The phosphate donor in this reaction is ATP, and the enzyme is ___. Answer hexokinase In glycolysis, when glucose enters a cell, it is immediately phosphorylated to form glucose-6- phosphate. The phosphate donor in this reaction is _______, and the enzyme is hexokinase. Answer ATP In glycolysis, when fructose-6-phosphate is preparing to split the phosphate donor in this reaction is ATP, and the enzyme is ________. Answer phosphofructokinase-1 In the last reaction of glycolysis, ATP is formed by the direct transfer of a phosphate group from a metabolite to ADP. This process is referred to as: Answer substrate-level phosphorylation Under anaerobic condition, to which compound is pyruvate converted? Answer ethanol or lactate The process that extracts energy as ATP but does not consume O2 or change the concentration of NAD+/NADH: fermentation How many reactions are in glycolysis? 10 The reactions of glycolysis take place in/on the ___. cytosol How is ATP used in the initial steps of glycolysis? source for phosphorylation Which of the following is a cyclic pathway? a. CAC b. PDH c. glycolysis d. oxidative phosphorylation e. beta-oxidation a. CAC Which of the following is a ten-step pathway? a. CAC b. PDH c. glycolysis d. oxidative phosphorylation e. beta-oxidation c. glycolysis How many ATP molecules does NADH yield after oxidative phosphorylation? 2.5 ATP per 1 NADH How many ATP molecules does FADH2 yield after oxidative phosphorylation? 1.5 ATP per 1 FADH2 How many ATP molecules does GTP yield after oxidative phosphorylation? 1 ATP per 1 GTP What energy molecule(s) is/are produced directly in the citric acid cycle? 1 GTP, 1 FADH2, 3 NADH What molecule is missing in the following reaction? a. PDH b. isocitrate c. fumarate d. FADH2 e. succinyl-coA b. isocitrate The enzymes and coenzymes of the citric acid cycle are all present in the ___. mitochondria Where does pyruvate conversion to acetyl-coA production occur? mitochondria Cellular respiration is the process of cells taking ___ and producing ___ to generate energy. O2; CO2 The complete degradation of glucose via cellular respiration occurs in ___ phases. 3 What are the names of the three enzymes that convert pyruvate to acetyl coA? E1, E2, and E3 What coenzyme(s) are necessary for beta-oxidation? NAD+ and FAD Which of the following letters corresponds to the alpha-carbon of a fatty acid? A B C D E B (between C and COOH) The process for degrading fatty acids is commonly referred to as: beta-spiral In one step of the glycolysis pathway, a 6-carbon compound is broken down into two 3 carbon fragments, only one of which can be further degraded in the glycolysis pathway. What happens to the other 3-carbon fragment? After splitting the six-carbon into GAP and DHAP, only GAP can directly proceed in the glycolysis pathway. DHAP must be converted to GAP by triose phosphate isomerate to continue in the glycolysis pathway. Glucose contains __(A)__ carbon atoms. The oxidation of a glucose molecule utilizes __(B)__ ATP. Later, the __(C)__ 3-carbon products of glycolysis produce __(D)__ ATP by direct phosphorylation, which gives a net yield of 2 ATP. In addition, __(E)__ NADH are produced in glycolysis. Word bank: one, two, three, four, five, six (A) six (B) two (C) two (D) four (E) two Glucose contains __(A)__ carbon atoms. The preparatory phase of glycolysis consists of __(B)__ steps. The oxidation of glucose molecules utilizes two ATP molecules. Later, the two __(C)__-carbon products go glycolysis produce __(D)__ ATP by direct phosphorylation, which gives a net yield of two ATP. In addition, __(E)__ NADH are produced in glycolysis. Word bank: one, two, three, four, five, six (A) six (B) five (C) three (D) four (E) two Consider the fatty acid which has 20 carbons (below). A. How many cycles of beta-oxidation are required? Briefly explain. B. How many acetyl-coA are produced. Briefly explain. C. How many NADH and FADH2 are produced from beta-oxidation (only) of this molecule? A. 9 cycles are required. Each cycle removes 2-carbon units, and the final cycle produces 2 acetyl groups. B. 10 acetyl-coA groups are produced. 2 are produced on the last cycle. C. 9 NADH and 9 FADH2 molecules are produced. Each round produces 1 NADH and 1 FADH2. The complete oxidative catabolism of fatty acids to form CO2 and H2O occurs in 3 phases. Describe each of these 3 phases giving the important pathway in each phase and the energy molecules produced in each. The first phase includes fatty acid metabolism via beta-oxidation, in which the the molecule is degraded into acetyl-coA with the production of 1 FADH2 and 1 NADH per cycle. In the second phase, the acetyl-coA groups are shuttled through the citric acid cycle to generate GTP, NADH, FADH2, and the release of CO2. In the third phase, NADH and FADH2 coenzymes are oxidized in the mitochondria to yield ATP via oxidative phosphorylation. carbohydrates are water-soluble compounds generally stores in the __________ cytosol lipids store energy in specialized cells called ___________ adipocytes What is bioenergetics? study of how nutrients provide energy for organisms What is cellular metabolism all the reactions of a cell that permit life to persist what is anabolic reactions reactions that produce molecules what are catabolic reaction reactions that break down molecules How do waste and nutrient molecules cross the cellular membrane via integral proteins What are metabolic pathways? series of enzyme-catalyzed reactions that convert starting material into products What is the flux the time it takes for a compound to go from the beginning to end of a pathway carbohydrates and lipids after being degraded are broken down into intermediate acetyl-CoA What is Acetyl CoA? a 2-carbon compound to which a molecule of CoA (containing ribose and adenine) is attached the acetyl-CoA continues through the citric acid cycle to generate molecules of ______________________ nicotinamide adenine dinucleotide (NADH). The NADH is ultimately shuttled to the _____1___ transport chain (ETC) to generate ATP by ____2________ 1. electron 2. oxidative phosphorylation Where do the final steps of converting acetyl Co-A to ATP occur interior of the mitochondria Molecules such as pyruvate, ADP, and ATP can move across the membrane through integral proteins called __________ transporters What are transporters move only one molecule or type of molecule across the membrane Once in the ___1___ATP can be broken down enzymatically to ___2__, releasing energy to perform work 1. cytosol 2. ADP The net change in free-energy, ΔG, is ______________ for the enzymatic breakdown of ATP negative (-) ΔG value indicates that the process is__________ spontaneous what does ΔG'o indicate reaction was studied under a set of defined conditions, but practically the value indicates a spontaneous process. what is a molecule aside from NADH that is important to biochemical pathways FADH2 What is a benefit of the structural difference in FADH2 permits it to interact with different proteins, an advantage to complex systems How is ATP converted into ADP? enzyme catalyzed hydrolysis The degradation of carbohydrates begins with ____1______and ends with the 3 carbon ___2_____molecule. 1. six-carbon monosaccharides (hexoses) 2. pyruvate What other molecules are used as starting materials for glycolysis mannose and fructose Pyruvate, the end-product, can be further processed to __________ for energy extraction from the citric acid cycle acetyl-CoA What is glycolysis? a 10-step enzymatic pathway that breaks down glucose into pyruvate with energy production in the form of ATP and NADH The ten reactions occur in the _________since all molecules and enzymes involved are water-soluble. cytosol What is the preparatory phase of glycolysis reactions 1-5 invests energy into converting glucose into glyceraldehyde-3-phosphate What is the payoff phase of glycolysis? reactions 6-10 the energy investment in the first is recovered as NADH, ATP, and two molecules of pyruvate Reaction 1 is a phosphorylation step where a phosphate group is added to glucose by the enzyme as glucose enters the cell hexokinase The ΔG'o for step 1 of glycolysis is -16.7 kJ/mol What is step 1 of glycolysis Glucose is phosphorylated by ATP with enzyme hexokinase creating glucose-6 phosphate What occurs during steps 2-3 in glycolysis glucose-6-phosphate is converted to fructose-6-phosphate via phosphohexose isomerase What is the ΔG'o of reaction 2 +1.7 kJ/mo What is step 4 of glycolysis x-carbon glucose into two, three-carbon compounds: glyceraldehyde 3-phosphate (GAP) and dihydroxyacetone phosphate (DHAP) via aldolase What is step 5 of glycolysis DHAP molecule is converted to GAP so that there are now two molecules of GAP What is step 6 of glycolysis two NADH molecules are produced, with each providing 2.5 equivalents of ATP when transported to the electron transport chain (ETC What is step 7 of glycolysis 1,3-bisphosphoglycerate to 3-phosphoglycerate via phosphoglycerate kinase What are steps 8-9 of glycolysis 3-phosphoglycerate, steps eight and nine of glycolysis prepare for the final ATP-forming step by generating phosphoenolpyruvate What is step 9 of glycolysis phosphoenolpyruvate is converted to pyruvate via pyruvate kinase what are the products of preparatory phase -2ATP What are the totals of payoff phase 4 ATP 2 NADH What is the total of glycolysis 2 ATP and 2 NADH What is fermentation process that extracts energy as ATP but does not consume O2 or change the concentration of NAD+/NADH What is respiration Pyruvate produced by glycolysis can undergo aerobic oxidative catabolism to form CO2 and H2O What is cellular respiration cells taking in O2 and producing CO2 to generate energy What are the 3 steps of cellular respiration? 1. Glycolysis 2. Citric acid Cycle 3. Electron Transport Chain What is step 1 of cellular respiration glucose or another fuel molecule, such as a fatty acid, is oxidized to the two-carbon acetyl-CoA compound What is step 2 of cellular respiration acetyl-CoA groups are shuttled through the citric acid cycle to generate NADH or FADH2 molecules along with the release of CO2. What is step 3 of cellular respiration acetyl-CoA groups are shuttled through the citric acid cycle to generate NADH or FADH2 molecules along with the release of CO2. After glycolysis, pyruvate is shuttled into ___1_____, where it is converted to acetyl CoA by a ____2_____process, where CO2 is released 1. mitochondria 2. decarboxylation What is pyruvate dehydrogenase (PDH) a supramolecular complex with multiple copies of three different enzymes, named E1, E2, and E3, that catalyzes this multistep reaction What is the function of PDH regulates the reaction, limiting unnecessary production of acetyl-CoA. What are other names for the citric acid cycle Krebs cycle or tricarboxylic acid (TCA) cycle What is the function of the CAC convert the acetyl-CoA to energy molecules that are stored and used when necessary. What is step 1 of the CAC Acetyl-CoA combined with oxaloacetate to form citrate, and release CoA-SH. Catalyzed by citrate synthase What is citrate six-carbon compound that contains three carboxylic acid groups What is step 2 of the CAC Citrate isomerized to isocitrate, with intermediate cis-Aconitate. Catalyzed by cis Aconitase What is step 3 of the CAC Isocitrate oxidized and decarboxylated to produce alpha-ketogluterate and CO2 by isocitrate dehydrogenase. Intermediate oxalosuccinate NADH produced by reduction of NAD+. !!RATE LIMITING STEP!! What is step 4 of CAC Alpha-ketoglutarate converted to succinyl-CoA and (2nd) CO2 by alpha-ketogluterate dehydrogenase complex. NADH #2 produced. What is step 5 of CAC Succinyl-CoA is converted to succinate by succinyl-CoA synthetase, producing GTP (then ATP) What is step 6 of CAC Succinate oxidized to fumarate by succinate dehydrogenase. Only rxn to take place on inner membrane, not in matrix. Enzyme cov. bound to FAD, which is reduced to FADH2. what is step 7 of cac Malate is produced by hydrolysis of fumarate; catalyzed by fumerase. Only L-malate formed. What is step 8 of cac Dehydrogenation to give NADH The complete oxidation of glucose to carbon dioxide and water yields as many as ______________ATP molecules, which is a significant amount of energy. 32 What is the Beta-oxidation pathway Fatty acids broken down to yield acetyl-CoA, which then can enter the citric acid cycle The fatty acid chain is broken between the ---1---and --2--carbon, which yields the 2 carbon fragment of -CH2-COOH that becomes acetyl-CoA. 1. beta 2. alpha what enzyme is used in step 1 of glycolysis hexokinase what enzyme is used in step 2 of glycolysis phosphohexose isomerase what enzyme is used in step 4 of glycolysis aldolase what enzyme is used in step 5 of glycolysis triose phosphate isomerase what enzyme is used in step 6 of glycolysis glyceraldehyde-3-phosphate dehydrogenase what enzyme is used in step 7 of glycolysis phosphoglycerate kinase what enzyme is used in step 8 of glycolysis phosphoglycerate mutase Every 1 NADH rebuilds ___ ATP 2.5 what enzyme is used in step 9 of glycolysis enolase what enzyme is used in step 10 of glycolysis pyruvate kinase 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 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 produced Fill in the appropriate blanks in the following sentence. 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. A. What compound is the five-carbon molecule? (contains 5 carbons) B. Identify the four-carbon compounds. C. How many GTP molecules are produced per turn of this cycle? D. What is one reaction that is an equilibrium reaction? (give reaction number) A. α-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.