Chapter 8: Cellular Respiration
For each molecule of glucose, how many ATPs are synthesized in fermentation a) 0 b) 1 c) 2 d) 3
a) 0
The oxiding agent at the end of the electron transport chain is a) O2 b) NAD+ c) ATP d) FAD
a) O2
The main function of cellular respiration is the a) conversion of energy stored in the chemical bonds of glucose to an energy form that the cell can use b) recovery of NAD+ from NADPH c) conversion of kinetic to potential energy d) creation of energy in the cell
a) conversion of energy stored in the chemical bonds of glucose to an energy form that the cell can use
One purpose of the electron transport chain is to a) cycle NADH + H+ back to NAD+ b) uses the intermediates from the citric acid cycle c) break down pyruvate d) increase the number of protons in the mitochondrial matrix
a) cycle NADH + H+ back to NAD+
Which of the following does not occur in the mitochondria of eukaryotic cells? a) fermentation b) oxidative phosphorylation c) the citric acid cycle d) the electron transport chain
a) fermentation
What is an example of anabolic interconversion? a) gluconeogenesis b) lipids broken down into their constituents, glycerol and fatty acids c) proteins hydrolyzed to amino acids d) 2 acetyl coAs are added together to form glycerol
a) gluconeogenesis
A person on a dangerously severe diet will eventually suffer from malnutrition and even starvation. If a person doesn't eat enough to fuel sufficient ATP and NADH production for biological activities, energy sources will be depleted. Which of the following represents the correct order in which this depletion takes place? a) glycogen -> fats -> proteins b) fats-> glycogen -> proteins c) glycogen -> proteins -> fats d) fats -> proteins -> glycogen
a) glycogen -> fats -> proteins
In all cells, glucose catabolism begins with a) glycolysis b) fermentation c) pyruvate oxidation d) the citric acid cycle
a) glycolysis
NADH a) is a key electron carrier in redox reactions b) requires O2 to function c) is found only in prokaryotes d) binds with an acetyl group to form acetyl coA
a) is a key electron carrier in redox reactions
Most of the ATP made during the complete oxidation of glucose to CO2 and water is a) made by the mitochondrial ATP synthase b) made from substrate-level phosphorylation c) synthesized in the cytosol d) made directly by the citric acid cycle
a) made by the mitochondrial ATP synthase
The component of aerobic respiration that produces the most ATP per mile of glucose is a) oxidative phosphorylation b) the citric acid cycle c) glycolysis d) lactic acid fermentation
a) oxidative phosphorylation
When NADH donates 2 electrons to the NADH-Q reductase complex, which then passes the electrons to ubiquinone, ubiquinone becomes a) reduced b) oxidized c) phosphorylated d) aerobic
a) reduced
Acetyl CoA is a) formed within mitochondria by the reduction of pyruvate b) formed within mitochondria by the oxidation of fatty acids c) formed in the cytoplasm by the oxidation of glucose d) used for the synthesis of sugars
b) formed within mitochondria by the oxidation of fatty acids
Which process converts glucose to pyruvate, generating a small amount of ATP but no CO2 a) pyruvate oxidation (prep rxn) b) glycolysis c) the citric acid cycle d) respiratory chain
b) glycolysis
Under anaerobic conditions, pyruvate a) is converted to lactate or tricarboxylic acids b) is fermented to lactate or alcohol c) enters the citric acid cycle d) is reduced to lactate
b) is fermented to lactate or alcohol
When a person runs for an extended period of time, the main source of glucose for muscle cells comes from the breakdown of glycogen in the a) muscle b) liver c) electron transport chain d) lungs
b) liver
In eukaryotes, the organelle containing enzyme(s) necessary for aerobic cellular energy production is (are) the a) nucleus b) mitochondria c) Golgi apparatus d) lysosomes
b) mitochondria
When a molecule loses hydrogen atoms (as opposed to hydrogen ions), it becomes a) reduced b) oxidized c) redoxed d) hydrogenated
b) oxidized
The oxidation of malate to oxaloacetate is coupled to the reduction of NAD+ to NADH + H+ . In this process, NAD+ is an a) reducing agent b) oxidizing agent c) vitamin d) phosphate ester
b) oxidizing agent
Which statement regarding glycolysis is true? a) glucose is not catabolized b) oxygen is not required c) pyruvate is not formed d) ATP is not formed
b) oxygen is not required
Animals breathe in air containing O2 and breathe out air with less O2 and more CO2. The CO2 comes from a) hydrocarbons and the air b) the citric acid cycle c) glycolysis d) waste products
b) the citric acid cycle
More free energy is harvested during the citric acid cycle than during glycolysis, but only one mole of ATP is produced for each mole of acetyl coA that enters the cycle. Most of the remaining free energy released during the citric acid cycle is a) used to synthesize GTP b) used to reduce electron carriers c) lost as heat d) used to reduce pyruvate
b) used to reduce electron carriers
For each glucose oxidized, the products from the citric acid cycle include a) 2 CO2 b) 8 NADH c) 2 FADH2 d) 6 ATP
c) 2 FADH2
Electrons are shuttled from glycolysis and the citric acid cycle to the respiratory chain via a) ATP b) FADH2 c) FADH2 and NADH d) NADH
c) FADH2 and NADH
Which molecule from glycolysis or the citric acid pathway serves as the building block for lipid synthesis? a) alpha-ketoglutarate b) oxaloacetate c) acetyl coA d) pyruvate
c) acetyl coA
For the citric acid cycle to proceed, it is necessary for a) pyruvate to bind to oxaloacetate b) CO2 to bind to oxaloacetate c) an acetyl group to bind to oxaloacetate d) H2O to be oxidized
c) an acetyl group to bind oxaloacetate
When hydrogen ions are pumped from the mitochondrial matrix across the inner membrane into the intermembrane space, the result is the a) formation of ATP b) reduction of NAD+ c) creation of a proton gradient d) reduction of glucose to lactic acid
c) creation of a proton gradient
Like glycolysis, the compartment where fermentation occurs is in the a) mitochondria b) chloroplast c) cytoplasm d) mitochondrial matrix
c) cytoplasm
During which process is most ATP generated in the cell? a) glycolysis b) the citric acid cycle c) electron transport coupled with chemiosmosis d) fermentation
c) electron transport coupled with chemiosmosis
The synthesis of ATP from ADP and P is an ____ reaction. In mitochondria, ATP synthesis is driven by the flow of ____ down the concentration and electrical gradient established by ______ a) endergonic ; Na+ ions ; electron transport b) exergonic ; protons ; glycolysis c) endergonic ; protons ; electron transport d) exergonic ; Na+ ions ; glycolysis
c) endergonic ; protons ; electron transport
In eukaryotes, the proton-motive force allows protons to move passively through ATP synthase in which direction? a) From the outside of the cell to the cytosol b) From the mitochondrial matrix to the inner mitochondrial membrane space c) From the mitochondrial inner membrane space to the mitochondrial matrix d) From the cytoplasm to the mitochondrial matrix
c) from the mitochondrial inner membrane space to the mitochondrial matrix
Which of the following cellular metabolic processes is active in all cells, regardless of the presence or the absence of oxygen? a) the citric acid cycle b) electron transport c) glycolysis d) fermentation
c) glycolysis
Which of the following statements about metabolic pathways is incorrect? a) chemical transformations occur in a series of separate chemical reactions b) a specific enzyme catalyzes each transformation step c) in prokaryotes, reactions in a pathway are located in multiple compartments d) inhibitors that target some key enzymes in a pathway can slow the rate of reaction
c) in prokaryotes, reactions in a pathway are located in multiple compartments
What is the cellular location of the citric acid cycle? a) plasma membrane b) cytoplasm c) mitochondrial matrix d) mitochondrial inner membrane
c) mitochondrial matrix
Which of the following statements about redox reactions is true? a) oxidizing agents accept electrons b) oxidizing agents donate electrons c) oxidizing agents accept electrons and are reduced in the process d) a molecule that accepts electrons is said to be oxidized
c) oxidizing agents accept electrons and are reduced in the process
"Anaerobic conditions" means that there is an absence of a) glucose b) lactate c) oxygen d) oxygen dioxide
c) oxygen
The end products of glycolysis are a) pyruvate b) pyruvate, ATP, and NAD+ c) pyruvate, ATP, and NADH d) acetyl coA, ATP, and NADH
c) pyruvate, ATP, and NADH
ATP synthase is the protein complex that a) is hard to see under an electron microscope b) rotates when ATP is hydrolyzed in the mitochondrial matrix c) rotates when protons flow through it and ADP and P combine in the mitochondrial matrix d) transfers electrons from the inner mitochondrial space to the mitochondrial matrix
c) rotates when protons flow through it and ADP and P combine in the mitochondrial matrix
Energy production occurs in different cellular compartments. Which statement is true for eukaryotes? a) the conversion of glucose to pyruvate occurs in the mitochondria b) the conversion of pyruvate to lactate occurs in the mitochondria c) the conversion of pyruvate to CO2 and H2O occurs in the mitochondria d) the respiratory chain enzymes are found at the plasma membrane
c) the conversion of pyruvate to CO2 and H2O occurs in the mitochondria
Most ATP produced in our bodies is made a) by glycolysis b) in the citric acid cycle c) using ATP synthase d) from photosynthesis
c) using ATP synthase
The electron transport chain a) is the site of most reactions of the citric acid cycle b) synthesizes ATP c) pumps protons into the mitochondrial matrix during electron transport d) oxidizes the intermediate electron carriers, NADH, and FADH2
d) oxidizes the intermediate electron carriers, NADH and FADH2
H2O is a by-product of cellular respiration. The H2O is produced as a result of the a) combining of CO2 with protons b) conversion of pyruvate to acetyl coA c) degradation of glucose to pyruvate d) reduction of O2 at the end of the electron transport chain
d) reduction of O2 at the end of the electron transport chain
Energy production occurs in different cellular compartments. Which statement is true for prokaryotes? a) the conversion of glucose to pyruvate to pyruvate occurs on the plasma membrane b) the conversion of pyruvate to lactate occurs on the plasma membrane c) the conversion of pyruvate to CO2 and H2O occurs in the mitochondria d) the respiratory chain enzymes are found on the plasma membrane
d) the respiratory chain enzymes are found on the plasma membrane
Metabolic pathways are a) a series of separate chemical reactions leading to a complex chemical transformation b) a set of chemical transformational steps, each with a specific enzyme c) a way of transforming cellular energy d) vulnerable to inhibitors and activators that target some key enzymes in a pathway e) all of the above
e) all of the above
Prep rxn generates a) acetyl-coA b) NADH + H+ from NAD+ c) a change in free energy d) CO2 e) all of the above
e) all of the above
Oxidative phosphorylation has 2 major components: __________ and ___________ a) proton transport ; chemiosmosis b) electron transport ; chemiosmosis c) electron transport ; osmosis d) electron transport ; chemical reduction
b) electron transport ; chemiosmosis
In the complete oxidation of glucose, 6 CO2 molecules are formed per glucose molecule. The number of CO2 molecules released by glycolysis is _____, by pyruvate oxidation (prep rxn) is _____, and by the citric acid cycle is ____ a) 0 ; 0 ; 6 b) 0 ; 2 ; 4 c) 2 ; 2 ; 2 d) 1 ; 2 ; 3
b) 0 ; 2 ; 4
The drug 2,4-dinitrophenol (DNP) destroys the proton gradient across the inner mitochondrial membrane. What would be the effect of incubating isolated mitochondria in a solution of DNP a) O2 would no longer be reduced to H2O b) ATP synthesis would decline c) mitochondria would show a burst of increased ATP synthesis d) glycolysis would stop
b) ATP synthesis would decline
Reduced electron carriers are critical to the citric acid cycle because a) NADH and FADH2 can donate their electrons to the electron transport chain and be regenerated to allow glycolysis to continue b) NADH and FADH2 can donate their electrons to the electron transport chain and be regenerated to allow the citric acid cycle to continue c) FADH2 can donate its electrons to the electron transport chain and be regenerated to allow glycolysis to continue d) ATP can donate its electrons to the electron transport chain and be regenerated to allow the citric acid cycle to continue
b) NADH and FADH2 can donate their electrons to the electron transport chain and be regenerated to allow the citric acid cycle to continue
Overall, 4 molecules of ATP are produced by glycolysis. However, the products of glycolysis are 2 ATP molecules , 2 pyruvate molecules, and 2 NADH molecules. The ATP values don't match because a) glucose metabolism is inefficient b) glucose phosphate is formed from fructose phosphate c) glucose is degraded to CO2 d) 2 ATP are invested in the process of glycolysis
d) 2 ATP are invested in the process of glycolysis
What is the metabolic fate of pyruvate in anaerobic muscle? a) it is converted to acetyl coA b) it is sent through cellular respiration c) it is oxidized d) it is sent through fermentation
d) It is sent through fermentation
The end product of glycolysis is a) pyruvate b) the starting point for prep rxn c) the starting point for the fermentation pathway d) all of the above
d) all of the above
Which of the following is recycled and reused in cellular metabolism a) ADP b) NAD+ c) FAD d) all of the above
d) all of the above
Which of the following events is not a part of the respiratory electron transport chain? a) consumption of O2 b) formation of ATP c) formation of H2O d) formation of NADH
d) formation of NADH
Before starch can be used for ATP production in animal cells, it must be hydrolyzed to a) pyruvate b) fatty acids c) amino acids d) glucose
d) glucose
Glycolysis a) is the conversion of glucose to 2 molecules of lactate b) is an endergonic reaction c) is a reaction that follows pyruvate oxidation (prep rxn) d) is an oxidation-reduction process
d) is an oxidation-reduction process
The types of chemical reactions involved in the aerobic breakdown of glucose include a) reductions b) oxidations c) oxidations and phosphorylations d) oxidation- reductions and phosphorylations
d) oxidation-reductions and phosphorylations