Biology chapter 6
How many total ATP molecules are produced by 1 molecule of glucose completing cellular respiration? a) 2 b) 6 c) 24 d) 36
d) 36
An electron carrier, such as __________, can serve as a temporary energy-storage molecule and assumes this role when it is __________. a) NAD+ ... reduced b) NADH ... oxidized c) NAD+ ... oxidized d) NADH ... reduced
d) NADH ... reduced
The O2 required for __________ is supplied by __________. a) cellular respiration ... ATP b) CO2 ... cellular respiration c) breathing ... cellular respiration d) cellular respiration ... breathing
d) cellular respiration ... breathing
This molecule has the formula C6H12O6 and is split in half during glycolysis
glucose
What is the storage form of glucose used by animal cells which can be broken down for energy when glucose is used?
glycogen
Cellular respiration
happens when oxygen is present and includes glycolysis, krebs cycle, and electron transport
FADH2
high energy electron carrier produces fewer ATP's than NADH as its electrons pass through the Electron Transport Chain because it enters farther down the chain
Type of fermentation used by human muscles in low oxygen conditions and microorganisms to make yogurt, cheese, pickles, sauerkraut and kimchi
lactic acid
Where do ADP and P join to make ATP?
matrix
A muscle cell deprived of molecular oxygen will convert glucose to lactic acid to __________. a) gain energy through chemiosmosis b) transition into the citric acid cycle c) recycle NADH through fermentation d) gain 2 ATP through glycolysis
c) recycle NADH through fermentation
The overall efficiency of respiration is approximately __________. a) 0.50% b) 34% c) 94% d) 2%
b) 34%
Substrate-level phosphorylation directly generates ATP during a chemical reaction. As a single molecule of glucose is completely oxidized in the presence of oxygen, what is the net yield of molecules of ATP made by substrate-level phosphorylation? a) 2 ATP b) 4 ATP c) 32 ATP d) 6 ATP
b) 4 ATP
The NADH and FADH2 produced during the Krebs cycle pass their electrons down the ______________________________ to produce ATP
electron transport chain
__________ is to a mitochondrion as __________ is to a chloroplast. a) sunlight .... chemical energy b) glucose ... O2 c) organic molecules ... sunlight d) ATP ... CO2
c) organic molecules ... sunlight
Some human cells, such as nerve cells, are restricted to aerobic respiration to recycle NADH and FADH2. If these cells are deprived of oxygen, then __________. a) proton gradient formation would continue, but ATP synthase function would stop b) glycolysis could still continue indefinitely c) oxidative phosphorylation would come to a halt because there wouldn't be any oxygen to serve as an electron acceptor at the transport chain d) ATP production would continue because the cell would perform fermentation
c) oxidative phosphorylation would come to a halt because there wouldn't be any oxygen to serve as an electron acceptor at the transport chain
Glycolysis happens outside the mitochondria in the _______________ of the cell
cytoplasm
Where does glycolysis occur?
cytoplasm
Classify each statement as a property of the ETC or chemiosmosis a) oxidizes NADH to NAD+ b) creates a proton gradient c) makes ATP using a proton gradient d) oxidizes FADH2 to FAD
a) ETC b) ETC c) chemiosmosis d) ETC
The passage of H+ ions through ______ ________________ causes it to spin and produce ATP.
ATP synthase
What is the chemical equation for cellular respiration?
C6H12O6 + 6O2 → 6H2O + 6CO2 + energy
Citric acid
a 6 carbon molecule that is produced first when acetyl-CoA joins with a 4 carbon molecule to enter the Krebs cycle
During cellular respiration, glucose is oxidized. However, an intermediate, __________, can be siphoned off and used to synthesize fats. a) pyruvate b) ATP c) glyceraldeyhyde 3-phosphate d) glucose
c) glyceraldeyhyde 3-phosphate
This atmospheric gas is required for aerobic respiration
oxygen
Where are the enzymes for electron transport in bacteria (prokaryotes) if they don't have internal membranes?
plasma membrane/ cell membrane
Anaerobic
process that does not require oxygen
Aerobic
process that requires oxygen
What is the chemical equation for alcoholic fermentation?
pyruvate + NADH → ethanol + NAD+ + CO2
What is the chemical equation for lactic acid fermentation?
pyruvate + NADH → lactic acid + NAD+
If alcoholic fermentation is used to make bread dough rise, how come you don't become intoxicated when you eat the bread?
the alcohol evaporates
ATP
the molecule used by cells to store and transfer energy
Glycolysis
the process of splitting a glucose molecule into 2 pyruvic acid molecules
How are the chemical equations for cellular respiration and photosynthesis related?
they are reversible
Alcoholic fermentation
type of fermentation used to make bread dough rise and produce beer and wine.
Pyruvic acid
3 carbon molecule produced when glucose is broken in half during glycolysis
The carbon atoms in pyruvic acid end up as _____ in the atmosphere following the Krebs Cycle
CO2
Why does FADH2 produce fewer ATP molecules than NADH when it passes its electrons down the ETC?
FADH2 drops its electrons farther down the ETC
What are the products of oxidative phosphorlyation?
H20, ATP
What is the net production of ATP, pyruvate, and NADH when one molecule of glucose undergoes glycolysis? a) 2 ATP, 2 NADH, and 2 pyruvate b) 4 ATP, 1 NADH, and 2 pyruvate c) 4 ATP, 2 NADH, and 4 pyruvate d) 2 ATP, 1 NADH, and 1 pyruvate
a) 2 ATP, 2 NADH, and 2 pyruvate AND ADP
The energy production per each glucose molecule through the citric acid cycle is __________. a) 2 ATP, 6 NADH, 2 FADH2 b) 4 ATP, 8 NADH c) 2 ATP, 6 NADH d) 32 ATP
a) 2 ATP, 6 NADH, 2 FADH2
The carriers for energy and high energy electrons during glycolysis are _____________. (Choose as many that apply) a) ATP b) NADH c) FADH2 d) NADPH
a) ATP b) NADH
Which of the following are produced during the krebs cycle? (Choose all that apply) a) ATP b) NADH c) FADH d) CO2
a) ATP b) NADH c) FADH d) CO2
Which of the following equations accurately represents cellular respiration? a) C6H1206 + 602 → 6C02 + 6H20 + energy b) 6CO2 + 6O2 + energy → C6H12O6 + 6H2O c) 6CO2 + 6O2 + energy → C6H12O6 + 6H2O d) C6H12O6 + 6H20 + energy → 6 CO2 + 6O2
a) C6H1206 + 602 → 6C02 + 6H20 + energy
Which high energy electron carrier is regenerated during fermentation that allows cells to continue to make ATP using glycolysis? a) NADH+ b) NADPH c) ATP d) ADP
a) NADH+
Which of the following is true of the ETC? a) The movement of electrons down the ETC drives the formation of a proton gradient b) The movement of H+ ions across the inner membrane of the mitochondria drives the transfer of electrons down the ETC c) The movement of H+ ions through ATP synthase drives the transfer of electrons down the ETC d) The movement of electrons down the ETC drives the movement of ADP and phosphate through ATP synthase
a) The movement of electrons down the ETC drives the formation of a proton gradient
What two-carbon precursor molecule from carbohydrate metabolism is used to produce fatty acids? a) acetyl-coa b) ATP c) glucose d) pyruvate
a) acetyl-coa
Which of the following occur during the Krebs cycle? (Choose 2) a) acetyl-coa combines with oxaloacetate to form citrate b) NAD+ is reduced to form NADH c) FADH2 accepts two electrons in order to form FAD d) pyruvate is converted into acetyl-coa
a) acetyl-coa combines with oxaloacetate to form citrate b) NAD+ is reduced to form NADH
Because cellular respiration requires oxygen it is said to be __________. a) aerobic b) anaerobic
a) aerobic
What kind of fermentation is used by bacteria and yeast to make beer and wine? a) alcoholic acid fermentation b) lactic acid fermentation
a) alcoholic acid fermentation
What kind of fermentation is used by yeast to make bread dough rise? a) alcoholic acid fermentation b) lactic acid fermentation
a) alcoholic acid fermentation
Besides sugars and fats, organisms can use other molecules as fuel for cellular respiration. When protein molecules are used, __________ are produced as waste. a) amino groups b) molecules of lactic acid c) fatty acids d) sugar molecules
a) amino groups
Which of the following happens as electrons pass down the ETC? (Choose all that apply) a) energy from the moving electrons transports H+ ions into the intermembrane space b) carbon dioxide is released c) energy from H+ ions crossing back into the matrix causes ATP synthase to make ATP d) water is produced
a) energy from the moving electrons transports H+ ions into the intermembrane space c) energy from H+ ions crossing back into the matrix causes ATP synthase to make ATP d) water is produced
In the equation for cellular respiration, __________ is oxidized, and __________ is reduced. a) glucose ... oxygen b) oxygen ... ATP c) carbon dioxide ... water d) ATP ... oxygen
a) glucose ... oxygen
Which stage of cellular respiration produces the most ATP? a) glycolysis b) krebs cycle c) electron transport d) acetyl-coa charging
a) glycolysis
What is the main transformation that occurs during glycolysis? a) glycolysis produces ATP, pyruvate, and NADH by oxidizing glucose b) glycolysis produces pyruvate and ATP through by oxidizing glucose and NAD+ c) glycolysis produces ATP through the process of oxidative phosphorylation d) glycolysis produces CO2, NAD, and pyruvate by oxidizing glucose
a) glycolysis produces ATP, pyruvate, and NADH by oxidizing glucose
Which of the following statements is true regarding glycolysis? a) glycolysis can occur without the presence of oxygen b) glycolysis takes place in the mitochondria of a cell c) glycolysis is the final step in aerobic respiration d) glycolysis produces a net of 1 ATP, 1 NADH, and 2 pyruvate
a) glyoclysis can occur without the presence of oxygen
If oxygen is present, what will happen to the NADH produced in the reaction? a) its electrons will enter the ETC b) it will donate its H+ ions to make glucose c) it will join with ATP to make citric acid d) it will join with oxygen to make CO2
a) its electrons will enter the ETC
How do lactic acid and alcohol fermentation differ? (Choose all that apply) a) lactic acid fermentation can occur in large muscles in the human body, while alcohol fermentation occurs in yeast and some bacteria b) lactic acid fermentation produces a 2-carbon compound, while alcohol fermentation produces a 3-carbon compound c) carbon dioxide is released only during alcohol fermentation d) lactic acid fermentation produces lactic acid as a byproduct, and alcohol fermentation produces ethanol
a) lactic acid fermentation can occur in large muscles in the human body, while alcohol fermentation occurs in yeast and some bacteria c) carbon dioxide is released only during alcohol fermentation d) lactic acid fermentation produces lactic acid as a byproduct, and alcohol fermentation produces ethanol
Lungs are to breathing as __________ are to cellular respiration. a) mitochondria b) bronchi c) alveoli d) chloroplasts
a) mitochondria
What molecule is the final electron acceptor at the end of the ETC? a) oxygen b) carbon dioxide c) glucose d) NADH
a) oxygen
In oxidative phosphorylation, electrons are passed from one electron carrier to another. The energy released is used to __________. a) pump hydrogen ions (H+) across the mitochondrial membrane b) generate large amounts of NADH and FADH2 c) synthesize carbon dioxide d) form ATP during glycolysis
a) pump hydrogen ions (H+) across the mitochondrial membrane
Which 3-carbon molecule is one of the final products of glycolysis? a) pyruvate b) glucose c) ADP d) 2-phosphoglycerate
a) pyruvate
Name the 3 carbon molecule produced when glucose is broken in half during glycolysis. a) pyruvic acid b) lactic acid c) acetyl-coa d) citric acid
a) pyruvic acid
Identify each of the following molecules as reactants or products of the Krebs cycle a) acetyl-coa b) carbon dioxide c) NAD+ d) NADH e) FADH2 f) FAD
a) reactant b) product c) reactant d) product e) product f) reactant
Which of the following is true regarding chemiosmosis? a) the energy from a proton gradient is used to make ATP b) chemiosmosis regenerates electron carriers like NADH and FADH2 c) ATP synthesis creates a proton gradient that causes electon flow through an ETC d) a temperature gradient drives ATP synthesis
a) the energy from a proton gradient is used to make ATP
Which of the following is true of the ETC? a) the movement of electrons down the ETC drives the formation of a proton gradient b) the movement of H+ ions across the inner membrane of the mitochondria drives the transfer of electrons down the ETC c) the movement of H+ ions through ATP synthase drives the transfer of electrons down the ETC d) the movement of electrons down the ETC drives the movement of ADP and phosphate through ATP synthase
a) the movement of electrons down the ETC drives the formation of a proton gradient
Why is the citric acid cycle called a cycle? a) the two-carbon acetyl group is transferred to the citric acid cycle utilizing Coenzyme A (CoA) where it binds to oxaloacetate, thereby regenerating citrate in cyclical fashion b) NAD+ and FAD are recycled c) glucose is cycled around and resynthesized d) NADH is recycled in the electron transport chain.
a) the two-carbon acetyl group is transferred to the citric acid cycle utilizing Coenzyme A (CoA) where it binds to oxaloacetate, thereby regenerating citrate in cyclical fashion
What is the ultimate destination of the electrons that are extracted from glucose during cellular respiration? a) they are used during the formation of water b) they result in the formation of heat c) they are donated to NAD+ d) they are used to form ATP by chemiosmosis
a) they are used during the formation of water
A gram of fat oxidized by cellular respiration produces approximately __________ as much ATP as a gram of carbohydrate. a) twice b) 4 times c) 10 times d) half
a) twice
When do oragnisms use anaerobic pathways to generate energy? a) when there is not enough oxygen available to undergo aerobic cellular respiration b) when the krebs cycle is moving too slowly c) when glucose is available as a reactant d) when the cytoplasm is unavailable for cellular respiration
a) when there is not enough oxygen available to undergo aerobic cellular respiration
Fat is the most efficient molecule for long-term energy storage, even compared to carbohydrates, because __________. a)with their numerous hydrogen atoms, fats provide an abundant source of high-energy electrons b) compared to carbohydrates, fat produces fewer toxic by-products when it's metabolized c) when compacted, fat occupies less volume than an equivalent amount of carbohydrate d) fats can directly enter the electron transport chain, the phase of respiration that produces the most ATP
a)with their numerous hydrogen atoms, fats provide an abundant source of high-energy electrons
This molecule forms when coenzyme a attaches to two carbons from pyruvic acid
acetyl- co a
Which of the following correctly describes the structure of ATP and how it provides energy? a) ATP contains a 5-carbon sugar, three phosphate groups, and an adenine base, Energy is released when the bond between the adenine base and the sugar is broken. b) ATP contains a 5-carbon sugar, three phosphate groups, and an adenine base. Energy is released when the bond between the second phosphate group and third phosphate group is broken. c) ATP contains a 6-carbon sugar, two phosphate groups, and an adenine base. Energy is released when a single phosphate group is added to the existing two phosphate groups. d)ATP contains a 6-carbon sugar, three phosphate groups, and an adenine base. Energy is released when bonds within the 6-carbon molecule are broken.
b) ATP contains a 5-carbon sugar, three phosphate groups, and an adenine base. Energy is released when the bond between the second phosphate group and third phosphate group is broken.
Which of the following best describes the electron transport chain? a) Hydrogens are added to CO2 to make an energy-rich compound. b) Electrons are passed from one carrier to another, releasing a little energy at each step. c) The two-carbon acetyl group is fully oxidized to CO2. d) Electrons are pumped across a membrane by active transport.
b) Electrons are passed from one carrier to another, releasing a little energy at each step.
Given the relatively modest number of calories burned by anything but the most vigorous of activities, how can people consume over 2,000 kilocalories a day yet maintain a healthy body weight? a) Not all calories are created equal, so a person who consumes 2,000 kilocalories of sugar- and fat-laden processed food will gain weight, whereas a person who consumes 2,000 calories of non-processed, low-carbohydrate food will not. b) Most of the energy consumed in food is spent maintaining the body's functions over the course of a day, so a healthy amount of daily exercise would require only a modest increase in the number of kilocalories consumed to maintain a healthy weight. c) They can't, and this has led to a problem of obesity in the United States. d) Those who exercise vigorously for one to two hours per day can maintain a healthy body weight while consuming the recommended average number of kilocalories per day.
b) Most of the energy consumed in food is spent maintaining the body's functions over the course of a day, so a healthy amount of daily exercise would require only a modest increase in the number of kilocalories consumed to maintain a healthy weight.
In cellular respiration, which of the following outcomes is the result of electrons moving through the electron transport chain (or its components)? a) ADP is phosphorylated to make ATP b) a proton gradient is formed c) carbon dioxide is formed d) oxygen gas is formed
b) a proton gradient is formed
Which product of pyruvate osidation enters the Krebs cycle? a) carbon dioxide b) acetyl-coa c) NADH d) glucose
b) acetyl-coa
Which of the following is true of electron carriers NADH and FADH2? a) FADH2 is a better electron donor than NADH because it allows more H+ ions to be pumped across the membrane b) all of the electrons that enter the transport chain are produced during earlier phases of cellular respiration c) NADH and FADH2 are single-use molecules so once they donate their electrons, they cannot be used again d) NADH is the oxidized form of NAD+ and FADH2 is the reduced form of FADH
b) all of the electrons that enter the transport chain are produced during earlier phases of cellular respiration
Since fermentation does not require oxygen it is said to be _______________. a) aerobic b) anaerobic
b) anaerobic
In an experiment, mice were fed glucose (C6H12O6) containing a small amount of radioactive carbon. The mice were closely monitored, and in a few minutes, radioactive carbon atoms showed up in __________. a) water b) carbon dioxide c) ATP d) heat
b) carbon dioxide
In what part of the cell does the Krebs cycle take place? a) mitochondria b) chloroplast c) ribosome d) cytoplasm (cytosol)
b) chloroplast
Which of the following is the source of the energy that produces the chemiosmotic gradient in mitochondria? a) ATP b) electrons c) cytochrome c d) ATP synthase
b) electrons
What kind of fermentation is used by bacteria to make cheese, yogurt, and sour cream? a) alcoholic acid fermentation b) lactic acid fermentation
b) lactic acid fermentation
What kind of fermentation is used by muscle cells during rapid exercise when oxygen is low? a) alcoholic acid fermentation b) lactic acid fermentation
b) lactic acid fermentation
Recent data suggests that heat-generating brown fat is most active in __________. a) obese people exposed to cold temperatures b) lean people exposed to cold temperatures c) the elderly d) all individuals exposed to cold temperatures
b) lean people exposed to cold temperatures
A molecule that functions as the electron donor in a redox reaction __________. a) gains electrons and becomes oxidized b) loses electrons and becomes oxidized c) gains electrons and becomes reduced d) loses electrons and becomes reduced
b) loses electrons and becomes oxidized
Bacteria have no membrane-enclosed organelles. However, some still generate ATP through cellular respiration. Where might the electron transport chain be found in these organisms? a) nucleoid region b) plasma membrane c) cytoplasm d) mitochondria
b) plasma membrane
Sunlight is essential for the varied life on earth. Sunlight provides energy to photosynthetic organisms by providing ____________. a) heat to leaves, which is converted to useful energy for work b) the energy necessary to power the rearrangement of chemical bonds in H2O and CO2 to make organic molecules such as glucose c) the energy required to drive cellular respiration d) heat to leaves, which is used to synthesize chloroplasts
b) the energy necessary to power the rearrangement of chemical bonds in H2O and CO2 to make organic molecules such as glucose
Which of the following is true regarding the yield of ATP during aerobic cellular respiration? a) the theoretical yield of ATP from aerobic cellular respiration is 30 ATP, but often the actual yield is much higher b) the theoretical vield of ATP from aerobic cellular respiration is 38 ATP, but often times the actual yield is lower c) it is impossible to determine the theoretical yield of ATP from aerobic respiration d) aerobic cellular respiration always yields 38 ATP once the process has completed
b) the theoretical vield of ATP from aerobic cellular respiration is 38 ATP, but often times the actual yield is lower
Where do the carbon atoms in pyruvic acid end up following the krebs cycle? (Choose all that apply) a) they enter the ETC and make ATP b) they become a part of a carbon dioxide molecule and end up in the atmosphere c) they join with citric acid to make acetyl-coa d) they build up in the intermembrane space
b) they become a part of a carbon dioxide molecule and end up in the atmosphere c) they join with citric acid to make acetyl-coa
Through respiration, humans breathe in O2 and breathe out CO2. However, what would happen if we did not breathe in O2? a) we would not be able to perform lactic acid fermentation b) we would not make enough ATP to meet our energy requirements c) we would not be able to synthesize organic molecules from inorganic molecules d) we would not have enough enzymes to catalyze reactions
b) we would not make enough ATP to meet our energy requirements
Krebs cycle
breaks down pyruvic acid into carbon dioxide and produces NADH, FADH2, and ATP
Since glycolysis produces 4 ATP molecules, this results in a NET GAIN of ____ ATPs a) 4 b) 3 c) 2 d) 1
c) 2
The movement of which ion across the membrane from the intermembrane space to the matrix causes ATP synthase to spin and make ATP? a) Na+ ions b) oxygen c) H+ ions d) water
c) H+ ions
In the absence of oxygen, cells need a way to regenerate which compound? a) lactic acid b) ethanol c) NAD+ d) carbon dioxide
c) NAD+
what molecule joins in the reaction to make Acetyl-CoA a) ATP b) NADP- c) coenzyme a d) citric acid
c) coenzyme a
In what part of the cell does glycolysis take place? a) nucleus b) ribosome c) cytoplasm (cytosol) d) mitochondria
c) cytoplasm (cytosol)
The electron transport chain is, in essence, a series of redox reactions that comprise the last stage of aerobic cellular respiration. During these redox reactions, __________. a) oxygen is oxidized as it picks up electrons at the very end of the electron transport chain b) ATP synthase allows hydrogen ions to move across the mitochondrial membrane c) electrons are transferred through a series of electron acceptors embedded within the inner mitochondrial membrane d) NADH is reduced as it donates electrons to the first complex involved in the electron transport chain
c) electrons are transferred through a series of electron acceptors embedded within the inner mitochondrial membrane
If oxygen is NOT present, glycolysis is followed by ___________________. a) krebs cycle b) electron transport chain c) fermentation
c) fermentation
___________ is the first step in cellular respiration that begins releasing energy stored in glucose. a) alcoholic fermentation b) lactic acid fermentation c) glycolysis d) electron transport chain
c) glycolysis
How do the mitochondria of brown fat cells differ from those of other cells? a) the mitochondria of brown fat cells are largely absent b) the mitochondria in these cells use different electron carriers c) ion channels in the inner mitochondrial membrane prevent the formation of a H+ gradient d) mitochondria in brown fat cells possess only a single membrane.
c) ion channels in the inner mitochondrial membrane prevent the formation of a H+ gradient
What happens to the energy that is released by electrons as they move through the electron transport chain? a) it breaks down glucose b) it makes NADH and FADH2 c) it pumps H+ through a membrane d) it oxidizes water
c) it pumps H+ through a membrane
When a car engine burns gasoline, the results of the reaction are similar to when cells burn glucose. Both reactions release carbon dioxide and water. In cells, the chemical energy in food is converted to ATP and heat. In a moving car, the chemical energy in gasoline is converted to __________. a) thermal energy and heat b) potential energy and heat c) kinetic energy and heat d) ATP and heat
c) kinetic energy and heat
Primarily, cellular respiration serves to __________. a) make food b) produce cell structures from chemical building blocks c) make ATP to power the cell's activities d) break down toxic molecules
c) make ATP to power the cell's activities
What is the purpose of embedding the electron transport chain in the membrane of a cell? a) the citric acid cycle can be compartmentalized from glycolysis b) NADH can donate electrons to an electron carrier only when it is embedded in a membrane c) the electron acceptors can transport H+ across the membrane, which is otherwise impermeable to H+ d) hydrogen ions (H+) are the only substances that can be pumped across this membrane.
c) the electron acceptors can transport H+ across the membrane, which is otherwise impermeable to H+
The enzyme ATP synthase catalyzes the phosphorylation of ADP to form ATP. In eukaryotic cells, the energy needed for this endergonic reaction is derived directly from __________. a) the fermentation of pyruvate to form lactic acid b) the movement of FADH2 from the cytoplasm to the mitochondria c) the movement of hydrogen ions across the mitochondrial membrane d) the reduction of NAD+ to form NADH
c) the movement of hydrogen ions across the mitochondrial membrane
Mitochondria
cell organelle which acts as the cell's power plant to burn glucose and store energy as ATP
This molecule reacts with pyruvic acid to release CO2, produce NADH, and acetyl-CoA
coenzyme a
Where are enzymes for the ETC located?
cristae
How many molecules are added to get glycolysis started? a) 1 b) 4 c) 3 d) 2
d) 2
Using the ATP generated during cellular respiration, the intermediates of glycolysis and the citric acid cycle, such as pyruvate and acetyl CoA, can be siphoned off and used to __________. a) create energy sources, such as glucose or amino acids, that are recycled back through respiration, thus allowing a continual source of ATP with relatively little food intake b) generate the ADP that is used to power biosynthetic pathways c) provide virtually all the heat needed to maintain body temperature d) build amino acids, fats, and sugars
d) build amino acids, fats, and sugars
Name the 6 carbon molecule that forms when Acetyl-CoA joins its 2 carbons to a 4 carbon molecule during the Krebs cycle. a) ATP b) pyruvic acid c) glucose d) citric acid
d) citric acid
In nutrient-rich environments (like your mouth), bacteria can use the provided amino acids to synthesize their proteins. However, should the environmental conditions change and become nutrient-poor, bacteria would need to synthesize their own amino acids. They can do this using __________. a) glucose b) glyceraldehyde 3- phosphate c) ATP d) citric acid cycle intermediates
d) citric acid cycle intermediates
A single glucose molecule produces about 32 molecules of ATP through the process of cellular respiration. However, this only represents approximately 34% of the chemical energy present in this molecule. The rest of the energy from glucose is __________. a) used directly for energy b) stored as fat c) used to make water from hydrogen ions and oxygen d) converted to heat
d) converted to heat
The function of cellular respiration is to __________. a) synthesize macromolecules from monomers b) reduce CO2 c) extract CO2 from the atmosphere d) extract usable energy from glucose
d) extract usable energy from glucose
Which of the following statements regarding aerobic cellular respiration is TRUE? a) oxidative phosphorylation in the inner mitochondrial membrane produces NADH b) most of the energy captured from the breakdown of glucose occurs during glycolysis c) the bulk of the ATP generated in cellular respiration in produced through substrate-level phosphorylation d) glucose is completely oxidized to form carbon dioxide
d) glucose is completely oxidized to form carbon dioxide
Which of the following shows the correct sequence during cellular respiration? a) electron transport chain → glycolysis → krebs cycle b) glycolysis → electron transport chain → krebs cycle c) krebs cycle → electron transport chain → glycolysis d) glycolysis → krebs cycle → electron transport chain
d) glycolysis → krebs cycle → electron transport chain
Aerobic cellular respiration completely breaks down a glucose molecule through glycolysis and the citric acid cycle. However, these two processes yield only a few ATPs. The majority of the energy the cell derived from glucose is __________. a) passed to the oxygen used in the electron transport chain b) stored in FAD and NAD+ c) lost as heat d) in NADH and FADH2
d) in NADH and FADH2
Sports physiologists at an Olympic training center want to monitor athletes to determine at what point their muscles begin to function anaerobically. They could do this by checking for a buildup of __________. a) ADP b) ATP c) carbon dioxide d) lactic acid
d) lactic acid
Gwen is investigating how exercise affects the rate at which she can squeeze a ball. After several minutes, she begins to experience muscle soreness and fatigue. She knows that this means her muscles are beginning to run out of oxygen. Which process is likely causing the soreness in her muscle cells? a) alcohol fermentation b) krebs cycle c) photosynthesis d) lactic acid fermentation
d) lactic acid fermentation
In cellular respiration, glucose __________ electrons, whereas __________ electrons. a) loses ... water gains b) gains ... water loses c) gains ... oxygen loses d) loses ... oxygen gains
d) loses ... oxygen gains
A molecule is oxidized when it __________. a) gains one or more electrons b) gains a hydrogen ion (H+) c) loses a hydrogen ion (H+) d) loses one or more electrons
d) loses one or more electrons
The electron transport chain is a series of electron carrier molecules. In eukaryotes, where is this structure found? a) rough endoplasmic reticulum b) smooth endoplasmic reticulum c) plasma membrane d) mitochondria
d) mitochondria
Which of the following statements about the Krebs cycle is most accurate? a) the Krebs cycle occurs as part of both cellular respiration and photosynthesis b) oxygen and water are produces in the Krebs cycle c) the Krebs cycle is the first step in cellular respiration d) not all living things engage in the Krebs cycle
d) not all living things engage in the Krebs cycle
Which 3-carbon molecule is one of the final products of glycolysis? a) 2-phosphoglycerate b) ADP c) glucose d) pyruvate
d) pyruvate
Fat is the most efficient molecule for long-term energy storage, even compared to carbohydrates, because __________. a) compared to carbohydrates, fat produces fewer toxic by-products when it is metabolized b) fats can directly enter the electron transport chain, the phase of respiration that produces the most ATP c) cells are able to compact fat such that it occupies far less volume than an equivalent amount of carbohydrate d) with their numerous hydrogen atoms, fats provide an abundant source of high-energy electrons
d) with their numerous hydrogen atoms, fats provide an abundant source of high-energy electrons
List the following steps of oxidative phosphorylation from beginning (top) to end (bottom) a) H+ ions are pumped across the mitochondrial membrane to establish an electrochemical gradient b) H+ ions flow down the gradient to generate ATP c) electrons are transferred to oxygen, causing it to split and take up H+ ions, which forms water d) electrons are transferred to molecules in the beginning of the electron transport chain
d, a, c, b
If oxygen is NOT present, glycolysis is followed by
fermentation
Cristae
folded inner membrane of mitochondria
As electrons pass down the electron transport chain, H+ ions build up in the _______ space.
intermembrane
What fills with H+ ions as electrons move down the concentration gradient?
intermembrane space
Where does oxygen act as the final electron acceptor to make water?
matrix
the area inside the cristae where the krebs cycle happens is the
matrix
