Biology Chapter 6
Carbon monoxide is a colorless, odorless, and toxic gas. Theoretically, if you were breathing carbon monoxide, how many ATP molecules could you produce from one glucose molecule?2 ATP 4 ATP 38 ATP 0 ATP
2 ATP
How many kilocalories are captured in ATP from 1.5 moles of glucose? 138 kcal 420 kcal 275 kcal 550 kcal
420 kcal
Humans use about ________ of their daily calories to maintain brain cells and power other life-sustaining activities. 90% 75% 25% 50%
75%
In the absence of oxygen, cells need a way to regenerate which compound? NAD+ carbon dioxide ethanol lactic acid
NAD+
Of the metabolic pathways listed below, the only pathway found in almost all organisms is ___. the citric acid cycle glycolysis cellular respiration the electron transport chain
glycolysis
Where does glycolysis occur in a eukaryotic cell? on the inner mitochondrial membrane within the intermembrane space of the mitochondrion in the cytoplasmic fluid in the mitochondria
in the cytoplasmic fluid
If you were able to stop the process of cellular respiration after completing electron transport but prior to chemiosmosis, you would find the pH of a mitochondrion to be at its lowest on the outer membrane. in the mitochondrial matrix. in the intermembrane space. on the inner membrane.
in the intermembrane space.
The mitochondrial cristae are an adaptation that increases the space for more copies of the electron transport chain and ATP synthase complexes. permits the expansion of mitochondria as oxygen accumulates in the mitochondrial matrix. carefully encloses the DNA housed within the mitochondrial matrix. helps mitochondria divide during times of greatest cellular respiration.
increases the space for more copies of the electron transport chain and ATP synthase complexes.
During cellular respiration, the energy in glucose is carried by electrons. is released all at once. becomes stored in molecules of ammonia. is used to manufacture glucose.
is carried by electrons
Respiration ________, and cellular respiration ________. is gas exchange . . . produces ATP produces ATP . . . is gas exchange produces glucose . . . produces oxygen uses glucose . . . produces glucose
is gas exchange . . . produces ATP
The principal molecules involved in transporting electrons to the electron transport chain are composed of _____. nucleotides amino acids sugars fatty acids
nucleotides
Bacteria that are unable to survive in the presence of oxygen are called obligate anaerobes. aerotolerant anaerobes. obligate aerobes. facultative anaerobes.
obligate anaerobes.
A mutant protist is found in which some mitochondria lack an inner mitochondrial membrane. Which of the following pathways would be completely disrupted in these mitochondria? glycolysis biosynthesis oxidative phosphorylation alcoholic fermentation
oxidative phosphorylation
During glycolysis, a molecule of glucose is partially oxidized. What is the net gain of ATP and NADH for each glucose molecule? 4 ATP and 10 NADH 32 ATP and 10 NADH 6 ATP and 10 NADH 2 ATP and 2 NADH
2 ATP and 2 NADH
Sodium fluoroacetate, or compound 1080, is a rodent poison that probably disrupts the citric acid cycle. In the body, the molecule is converted to a compound that prevents citrate from being used. Initially, when first exposed to this molecule, what is the theoretical energy produced per glucose molecule through the process of cellular respiration? 2 ATP, 4 NADH, and 0 FADH2 0 ATP, 0 NADH, and 0 FADH2 2 ATP, 2 NADH, and 0 FADH2 2 ATP, 4 NADH, and 2 FADH
2 ATP, 4 NADH, and 0 FADH2
The energy production per glucose molecule through the citric acid cycle is _____. 38 ATP 2 ATP, 6 NADH, 2 FADH2 2 ATP, 6 NADH 4 ATP, 8 NADH
2 ATP, 6 NADH, 2 FADH2
When did the level of oxygen in Earth's atmosphere become high enough to sustain aerobic respiration? 2.7 billion years ago 3.5 billion years ago 1.0 billion years ago 1.5 billion years ago
2.7 billion years ago
Substrate-level phosphorylation directly generates ATP during a chemical reaction. As a single molecule of glucose is completely oxidized, in the presence of oxygen, how many molecules of ATP are gained by substrate-level phosphorylation?6 ATP 38 ATP 4 ATP 2 ATP
4 ATP
The overall efficiency of respiration is approximately _____. 2% 0.50% 94% 40%
40%
In preparing pyruvate to enter the citric acid cycle, which of the following steps occurs? Carbon dioxide must be present for pyruvate to enter the citric acid cycle. Pyruvate is reduced by oxidizing an NAD+ to an NADH. A compound called coenzyme A binds to a two-carbon fragment. Oxygen atoms are formed into oxygen gas.
A compound called coenzyme A binds to a two-carbon fragment.
In cellular respiration, which of the following is performed directly by the electron transport chain (or its components)? A proton gradient is formed. ADP is phosphorylated to make ATP. Oxygen gas is formed. Carbon dioxide is formed.
A proton gradient is formed.
During chemiosmosis, H+ ions serve as the final electron acceptor. ATP is synthesized when H+ ions move through a channel in ATP synthase. energy is released as H+ ions move freely across mitochondrial membranes. a concentration gradient is generated when large numbers of H+ ions are passively transported from the matrix of the mitochondrion to the mitochondrion's intermembrane space.
ATP is synthesized when H+ ions move through a channel in ATP synthase.
Why is the citric acid cycle called a cycle? Acetyl CoA binds to oxaloacetate that is restored at the end of the cycle. NAD+ and FAD are recycled. NADH is recycled in the electron transport chain. Glucose is cycled around and resynthesized.
Acetyl CoA binds to oxaloacetate that is restored at the end of the cycle.
The overall equation for the cellular respiration of glucose is C6H12O6 + energy → 6 CO2+ 6 H2O + 6 O2. C5H12O6 + 6 O2 → 5 CO2 + 6 H2O + energy. C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + energy. 5 CO2 + 6 H2O → C5H12O6 + 6 O2 + energy.
C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + energy.
In the first stage of cellular respiration, two molecules of pyruvate are produced. In the remaining stages, a number of products are produced, including _____. These stages occur in the _____. CO2 ... mitochondria glucose ... mitochondria ATP ... cytoplasm water ... cytoplasm
CO2 ... mitochondria
When pyruvate is converted to acetyl CoA, _____.CO2 and ATP are formed one turn of the citric acid cycle is completed CO2 and NADH are formed CO2 and coenzyme A are formed
CO2 and NADH are formed
Which of the following statements regarding cellular respiration is false? Cellular respiration releases heat. Cellular respiration produces water. Cellular respiration is a single chemical reaction with just one step. Cellular respiration produces carbon dioxide.
Cellular respiration is a single chemical reaction with just one step.
Which of the following statements about the energy yields from cellular respiration is true? Cellular respiration is more efficient at harnessing energy from glucose than car engines are at harnessing energy from gasoline. The heat produced during cellular respiration is only a tiny fraction of the chemical energy available in a glucose molecule. Cellular respiration converts the kinetic energy of glucose into chemical energy. Cellular respiration converts all of the energy in glucose into high-energy ATP bonds.
Cellular respiration is more efficient at harnessing energy from glucose than car engines are at harnessing energy from gasoline.
Which of the following statements regarding the chemical grooming of pyruvate is false? Each pyruvate loses a carbon atom, which is released as CO2. Each pyruvate molecule has a CO2 added and then joins with an NADH. Two pyruvate molecules together contain less chemical energy than was found in the original glucose molecule. Two molecules of pyruvate are each converted into two-carbon molecules joined to a coenzyme A molecule.
Each pyruvate molecule has a CO2 added and then joins with an NADH.
Which of the following best describes the electron transport chain? Hydrogens are added to CO2 to make an energy-rich compound. Acetyl CoA is fully oxidized to CO2. Electrons pass from one carrier to another, releasing a little energy at each step. Electrons are pumped across a membrane by active transport.
Electrons pass from one carrier to another, releasing a little energy at each step.
Which of the following serves primarily as a hydrogen-atom carrier molecule in cells?RNA ATP CO2 FAD
FAD
Which of the following statements regarding food is false? Food provides the raw materials for biosynthetic pathways that consume ATP. Food provides the raw materials for biosynthetic pathways that make molecules for cellular repair and growth. Food provides the raw materials for biosynthetic pathways that can produce sugar by a process that is the exact opposite of glycolysis. Food provides the raw materials for biosynthetic pathways that can produce molecules that are not actually present in the original food.
Food provides the raw materials for biosynthetic pathways that can produce sugar by a process that is the exact opposite of glycolysis.
Which of the following statements regarding glycolysis is false? Glycolysis is considered to be an ancient metabolic system because it is the most efficient metabolic pathway for ATP synthesis. Glycolysis is considered to be an ancient metabolic system because it occurs universally. Glycolysis is considered to be an ancient metabolic process because it does not require oxygen. Glycolysis is considered to be an ancient metabolic process because it is not located in a membrane-bound organelle.
Glycolysis is considered to be an ancient metabolic system because it is the most efficient metabolic pathway for ATP synthesis.
We inhale O2 and we exhale CO2. Carbon dioxide is produced _____. during the formation of pyruvate In the reaction that creates acetyl CoA (coenzyme A) from pyruvate when oxygen acquires electrons and protons at the end of the electron transport chain during the electron transfer steps of oxidative phosphorylation
In the reaction that creates acetyl CoA (coenzyme A) from pyruvate
What happens to the energy that is given up by electrons as they move through the electron transport chain? It makes NADH and FADH2. It oxidizes water. It breaks down glucose. It pumps H+ through a membrane
It pumps H+ through a membrane.
Dinitrophenol (DNP) is a highly toxic membrane uncoupler. What happens when DNP makes the phospholipid bilayer of inner mitochondrial membranes permeable to protons (H+)? The proton pumps of the inner mitochondrial membrane would cease to function. NADH or FADH2 would no longer provide electrons to the electron transport chain. The redox reactions of the electron transport chain cease. Many protons would bypass ATP synthase, leading to a sharp decline in ATP synthesis.
Many protons would bypass ATP synthase, leading to a sharp decline in ATP synthesis.
During cellular respiration, electrons move through a series of electron carrier molecules. Which of the following statements about this process is true? The electrons move from carriers that have more affinity for them to carriers that have less affinity for them. The electrons release large amounts of energy each time they are transferred from one carrier to another. Molecular oxygen is reduced when it accepts electrons and forms water. Molecular oxygen is eventually oxidized by the electrons to form water.
Molecular oxygen is reduced when it accepts electrons and forms water.
Given the relatively modest number of calories burned by anything but the most vigorous activities, why can people consume over 2,000 kilocalories a day, yet maintain a healthy body weight? People really should exercise vigorously for one to two hours per day. They can't, and this has led to a problem of obesity in the United States. Most of the energy consumed in food is spent maintaining the body's functions, so only a fraction of food energy needs to be burned in exercise. 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 nonprocessed, low-carbohydrate food will not.
Most of the energy consumed in food is spent maintaining the body's functions, so only a fraction of food energy needs to be burned in exercise.
The electron transport chain is, in essence, a series of redox reactions that conclude cellular respiration. During these redox reactions, _____. ATP synthase removes hydrogen ions and pumps them across the mitochondrial membrane NAD+ is reduced, which then oxidizes an electron acceptor in the electron transport chain NADH is reduced as it donates electrons to the first complex involved in the electron transport chain all the carriers pump H+ across the mitochondrial membrane, forming a gradient that is used to drive ATP synthesis
NAD+ is reduced, which then oxidizes an electron acceptor in the electron transport chain
At the end of the citric acid cycle, most of the energy remaining from the original glucose is stored in ATP. pyruvate. CO2. NADH.
NADH
Once the citric acid cycle has been completed, most of the usable energy from the original glucose molecule is in the form of _____.NADH acetyl CoA CO2 ATP
NADH
The end products of glycolysis include NADH. acetyl CoA. citric acid. O2.
NADH
In fermentation, ________ is ________. NADH . . . reduced ethanol . . . oxidized NAD+ . . . oxidized NADH . . . oxidized
NADH . . . oxidized
What molecule is required to move pyruvate to the citric acid cycle? NADH ATP O2 FADH2
O2
Consider the figure below. _____ is to a mitochondrion as _____ is to a chloroplast. O2 ... CO2 ATP ... CO2 Sunlight ... chemical energy Glucose ... O2
O2 ... CO2
Which of the following statements about the energy yield of aerobic respiration is false? Oxidative phosphorylation resulting from 1 glucose molecule yields about 12 ATP molecules. Most of the ATP derived during aerobic respiration results from oxidative phosphorylation. The total yield of ATP molecules per glucose molecule is about 32. Less than 50% of the chemical energy available in glucose is converted to ATP energy.
Oxidative phosphorylation resulting from 1 glucose molecule yields about 12 ATP molecules.
Which of the following statements regarding photosynthesis and cellular respiration is true? Photosynthesis occurs in mitochondria and in chloroplasts. Photosynthesis occurs in mitochondria, and cellular respiration occurs in chloroplasts. Cellular respiration occurs in mitochondria and in chloroplasts. Photosynthesis occurs in chloroplasts, and cellular respiration occurs in mitochondria.
Photosynthesis occurs in chloroplasts, and cellular respiration occurs in mitochondria.
When an organism such as a yeast lives by fermentation, it converts the pyruvate from glycolysis into a different compound, such as alcohol. Why doesn't it secrete the pyruvate directly? The conversion is needed to regenerate the molecules needed for glycolysis. The conversion yields one NADH per pyruvate molecule. The conversion yields 32 ATP per pyruvate molecule. A buildup of pyruvate in the surrounding environment would be too toxic.
The conversion is needed to regenerate the molecules needed for glycolysis.
Which of the following statements about the inner mitochondrial membrane is false? Electron carriers are found in the inner mitochondrial membrane. ATP synthase is found in the inner mitochondrial membrane. A gradient of H+ exists across the inner mitochondrial membrane. The inner mitochondrial membrane plays a role in the production of pyruvate.
The inner mitochondrial membrane plays a role in the production of pyruvate.
What is the purpose of embedding the electron transport chain in the membrane of a cell? NADH can donate electrons to an electron carrier only when it is embedded in a membrane. Hydrogen ions (H+) are the only substances that can be pumped across this membrane. The membrane is impermeable to H+. The citric acid cycle can be compartmentalized from glycolysis.
The membrane is impermeable to H+.
What is the fate of the electrons that are stripped from glucose during cellular respiration? They are donated to NADH. They result in the formation of heat. They are used to form water. They are used to form ATP by chemiosmosis
They are used to form water.
Which statement describes the citric acid cycle? This process converts pyruvic acid to acetyl CoA. This process splits glucose in half and produces 2 ATPs for each glucose. This process produces some ATP and carbon dioxide in the mitochondrion. This process joins 2 pyruvic acid molecules into a molecule of glucose. This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration.
This process produces some ATP and carbon dioxide in the mitochondrion.
Which statement describes glycolysis? This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration. This process produces some ATP and carbon dioxide in the mitochondrion. This process converts pyruvic acid to acetyl CoA. This process joins 2 pyruvic acid molecules into a molecule of glucose. This process splits glucose in half and produces 2 ATPs for each glucose.
This process splits glucose in half and produces 2 ATPs for each glucose.
Which statement describes the electron transport chain? This process splits glucose in half and produces 2 ATPs for each glucose. This process converts pyruvic acid to acetyl CoA. This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration. This process produces some ATP and carbon dioxide in the mitochondrion. This process joins 2 pyruvic acid molecules into a molecule of glucose.
This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration.
Through respiration, humans breathe in O2 and breathe out CO2. However, what would happen if we did not breathe in O2?We would not have enough enzymes to catalyze reactions. We would not make enough ATP to meet our energy requirements We would not be able to synthesize organic molecules from inorganic molecules. We would not be able to perform lactic acid fermentation.
We would not make enough ATP to meet our energy requirements
The functioning of an electron transport chain is analogous to a person climbing a flight of stairs one step at a time. a Slinky toy going down a flight of stairs. a canoe going over a waterfall. a person leaping from the top to the bottom of a flight of stairs in one jump
a Slinky toy going down a flight of stairs.
The function of coenzyme A in the citric acid cycle is most like a limousine driver dropping off a couple at the school prom. a frog that turns into a prince. a kid jumping up and down on a trampoline. throwing a baited hook into a lake and catching a fish.
a limousine driver dropping off a couple at the school prom.
Which of the following processes produces the most ATP per molecule of glucose oxidized? All produce approximately the same amount of ATP per molecule of glucose. aerobic respiration lactic acid fermentation alcoholic fermentation
aerobic respiration
In yeast cells, alcohol is produced during the citric acid cycle. lactic acid is produced during anaerobic respiration. lactic acid is produced during glycolysis. alcohol is produced after glycolysis.
alcohol is produced after glycolysis
Besides sugars and fats, organisms can use other molecules as fuel for cellular respiration. When protein molecules are used, _____ are produced as waste. amino groups molecules of lactic acid sugar molecules fatty acids
amino groups
In the electron transport chain, the final electron acceptor is an oxygen atom. a molecule of carbon dioxide. a molecule of water. ADP.
an oxygen atom.
When proteins are used as a source of energy for the body, the proteins are converted mainly into intermediates of glycolysis or the citric acid cycle. are hydrolyzed to their constituent amino acids; electrons are stripped from the amino acids and passed to the electron transport chain. are hydrolyzed to glucose and converted to acetyl CoA, which enters the citric acid cycle. are converted into glucose molecules, which are fed into glycolysis.
are converted mainly into intermediates of glycolysis or the citric acid cycle.
During aerobic respiration, molecular oxygen (O2) is used _____.between the citric acid cycle and the electron transport chain to move NADH and FADH2 at the end of electron transport chain to accept electrons and form H2O between glycolysis and the citric acid cycle to split a carbon from pyruvate at the end of the citric acid cycle to cycle back to oxaloacetate
at the end of electron transport chain to accept electrons and form H2O
Carbon monoxide is a toxic gas because it directly _____. inhibits ATP synthase blocks the transfer of electrons to the final electron acceptor inhibits the oxidation of NADH changes the permeability of the membrane
blocks the transfer of electrons to the final electron acceptor
A small amount of ATP is made in glycolysis ___. using energy from the sun to perform photosynthesis by the transport of electrons through a series of carriers by the transfer of a phosphate group from a fragment of glucose to ADP (substrate-level phosphorylation) when electrons and hydrogen atoms are transferred to NAD+
by the transfer of a phosphate group from a fragment of glucose to ADP (substrate-level phosphorylation)
The energy yield from the complete aerobic breakdown of a single molecule of glucose is always 32 ATP. can vary depending on whether NADH passes its electrons to NAD+ or FAD. is less than the yield from anaerobic respiration. increases as the supply of oxygen increases.
can vary depending on whether NADH passes its electrons to NAD+ or FAD.
In an experiment, mice were fed glucose (C6H12O6) containing a small amount of radioactive oxygen. The mice were closely monitored, and in a few minutes radioactive oxygen atoms showed up in _____. NADH water carbon dioxide ATP
carbon dioxide
By-products of cellular respiration include NADH and ATP. oxygen and heat. carbon dioxide and water. FADH2 and NADH.
carbon dioxide and water.
Where does most of the ATP produced in cellular respiration come from?chemiosmosis glycolysis the citric acid cycle lactic acid fermentation
chemiosmosis
A culture of bacteria growing aerobically is fed glucose containing radioactive carbon and is then examined. During the citric acid cycle, radioactivity would first appear in oxaloacetic acid. citrate. CoA. NADH.
citrate
When growing in a nutrient-rich environment, bacteria can use the provided amino acids to synthesize their proteins. However, should the environment change, they can synthesize their amino acids using _____. glyceraldehyde-3-phosphate citrate ATP glucose
citrate
Which of the following is a result of glycolysis? conversion of glucose to two three-carbon compounds production of CO2 conversion of NADH to NAD+ a net loss of two ATPs per glucose molecule
conversion of glucose to two three-carbon compounds
A single glucose molecule produces about 38 molecules of ATP through the process of cellular respiration. However, this only represents approximately 38% of the chemical energy present in this molecule. The rest of the energy from glucose is _____.converted to heat stored as fat used directly for energy used to make water from hydrogen ions and oxygen
converted to heat
In a eukaryotic cell, the electron transport chain is precisely located in or on the _____.cristae of the mitochondrion cytoplasmic fluid plasma membrane intermembrane space of the mitochondrion
cristae of the mitochondrion
Cyanide differs from dinitrophenol in that cyanide makes the membrane of mitochondria leaky to H+ ions and prevents a concentration gradient from building up, while dinitrophenol blocks the passage of electrons through electron carriers. cyanide is highly toxic to human cells, while dinitrophenol is nontoxic. cyanide inhibits the production of ATP by inhibiting ATP synthase, while dinitrophenol causes mitochondrial membranes to become less permeable to H+ ions. cyanide is an electron transport blocker, while dinitrophenol makes the membrane of the mitochondrion leaky to H+ ions.
cyanide is an electron transport blocker, while dinitrophenol makes the membrane of the mitochondrion leaky to H+ ions.
Where in bacterial cells does the citric acid cycle occur?mitochondrion cytoplasm plasma membrane ribosome
cytoplasm
In biological systems, an important enzyme involved in the regulation of redox reactions is oxygen. glucose. dehydrogenase. ATP.
dehydrogenase.
During cellular respiration, NADH is the final electron acceptor. is reduced to form NAD+. delivers its electron load to the first electron carrier molecule. is chemically converted into ATP.
delivers its electron load to the first electron carrier molecule.
Fat Away prevents ATP from being made by destroying the H+ gradient that allows ATP synthase to work. preventing glycolysis from occurring. slowing down the citric acid cycle. preventing the conversion of NADH to NAD+.
destroying the H+ gradient that allows ATP synthase to work.
What is the mechanism of action for the enzyme ATP synthase? ATP is formed _____.from glucose in the absence of oxygen due to substrate-level phosphorylation in the absence of chemiosmosis due to the potential energy of a concentration gradient of hydrogen ions across a membrane
due to the potential energy of a concentration gradient of hydrogen ions across a membrane
Which of the following is the source of the energy that produces the chemiosmotic gradient in mitochondria? cytochrome c electrons ATP synthase ATP
electrons
During redox reactions, electrons are lost from one substance and added to another substance. the loss of electrons from one substance is called reduction. a substance that gains electrons is said to be oxidized. protons from one molecule replace the electrons lost from another molecule.
electrons are lost from one substance and added to another substance.
Which of the following are products of cellular respiration? oxygen and glucose energy to make ATP and carbon dioxide oxygen and energy to make ATP oxygen and carbon dioxide
energy to make ATP and carbon dioxide
Humans depend on oxygen to sustain life. However, at the cellular level, muscle cells are _____. facultative anaerobes aerobes strict anaerobes capable of alcohol fermentation
facultative anaerobes
Yeasts can produce ATP by either fermentation or oxidative phosphorylation; thus, they are strict anaerobes. strict aerobes. facultative anaerobes. facultative aerobes.
facultative anaerobes.
If you consume 1 g of each of the following, which will yield the most ATP? glucose starch protein fat
fat
If ATP accumulates in a cell feedback inhibition speeds up cellular respiration. feedback inhibition slows down cellular respiration. the cell receives a signal that there is a need for more energy. the rate of cellular respiration does not change
feedback inhibition slows down cellular respiration.
The major (but not sole) energy accomplishment of the citric acid cycle is the _____. formation of NADH and FADH2 completion of substrate-level phosphorylation formation of CO2 formation of ATP
formation of NADH and FADH2
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 derives from glucose is _____. found in NADH and FADH2 stored in FAD and NAD+ passed to the oxygen used in the electron transport chain lost as heat
found in NADH and FADH2
In the equation shown below, during cellular respiration _____ is oxidized and _____ is reduced.carbon dioxide ... water ATP ... oxygen glucose ... oxygen oxygen ... ATP
glucose ... oxygen
A culture of bacteria growing aerobically is fed glucose containing radioactive carbon and is then examined. As the bacteria metabolize the glucose, radioactivity will appear first in carbon dioxide. ATP. pyruvate. glucose-6-phosphate.
glucose-6-phosphate.
During cellular respiration, glucose is oxidized. However, an intermediate, _____, can be siphoned off and used to synthesize fats. glyceraldeyhyde-3-phosphate ATP glucose pyruvate
glyceraldeyhyde-3-phosphate
When a cell uses fatty acid for aerobic respiration, it first hydrolyzes fats to fatty acids and sugars. sugars and glycerol. glycerol and fatty acids. glycerol and amino acids.
glycerol and fatty acids.
What is the name of the process in which glucose is converted to pyruvate? fermentation glycolysis chemiosmosis oxidative phosphorylation
glycolysis
Which of the following metabolic pathways is common in aerobic and anaerobic metabolism?
glycolysis
During which of the following phases of cellular respiration does substrate-level phosphorylation take place? the citric acid cycle and glycolysis. oxidative phosphorylation. the citric acid cycle and oxidative phosphorylation.
glycolysis and the citric acid cycle
A chemist has discovered a drug that blocks phosphoglucoisomerase, an enzyme that catalyzes the second reaction in glycolysis. He wants to use the drug to treat people with bacterial infections. However, he can't do this because _____. bacteria are facultative anaerobes; they usually don't need to perform glycolysis human cells also perform glycolysis; the drug might also poison them glycolysis produces so little ATP that the drug will have little effect bacteria do not perform glycolysis
human cells also perform glycolysis; the drug might also poison them
To obtain energy from starch and glycogen, the body must begin by converting both starch and glycogen to fatty acids. hydrolyzing the starch to glucose and the glycogen to amino acids. removing one glucose at a time with a condensation reaction. hydrolyzing both starch and glycogen to glucose.
hydrolyzing both starch and glycogen to glucose.
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 _____. potential energy and heat thermal energy and heat kinetic energy and heat ATP and heat
kinetic energy and heat
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 _____. carbon dioxide ADP lactic acid ATP
lactic acid
In cellular respiration, glucose _____ electrons, whereas _____ electrons. gains ... oxygen loses gains ... water loses loses ... water gains loses ... oxygen gains
loses ... oxygen gains
A molecule is oxidized when it ____.gains a hydrogen ion (H+) loses an electron gains an electron loses a hydrogen ion (H+)
loses an electron
A molecule that functions as the electron donor in a redox reaction _____. loses electrons and gains energy gains electrons and gains energy loses electrons and loses energy gains electrons and loses energy
loses electrons and loses energy
Oxidation is the ________, and reduction is the ________. gain of electrons . . . loss of electrons loss of electrons . . . gain of electrons gain of protons . . . loss of protons gain of oxygen . . . loss of oxygen
loss of electrons . . . gain of electrons
The processes of photosynthesis and cellular respiration are complementary. During these energy conversions, some energy is saved in the chemical bonds of water, CO2 and O2. destroyed when the chemical bonds of glucose are made. lost in the form of heat. used to create light.
lost in the form of heat
In humans, oxygen and carbon dioxide are exchanged with the atmosphere via the _____. pancreas liver kidneys lungs
lungs
Primarily, cellular respiration serves to _____. produce cell structures from chemical building blocks break down toxic molecules make food make ATP to power the cell's activities
make ATP to power the cell's activities
The enzymes of the citric acid cycle are located in the outer mitochondrial membrane. matrix and inner mitochondrial membrane. cytoplasm. nucleus.
matrix and inner mitochondrial membrane.
The electron transport chain is a series of electron carrier molecules. In eukaryotes, where can this structure be found? mitochondria rough endoplasmic reticulum smooth endoplasmic reticulum plasma membrane
mitochondria
A scientist wants to study the enzymes of the citric acid cycle in eukaryotic cells. What part of the cell would she use as a source of these enzymes? mitochondrial inner membrane cytoplasm mitochondrial matrix plasma membrane
mitochondrial matrix
In what organelle would you find acetyl CoA formation, the citric acid cycle, and the electron transport chain? mitochondrion chloroplast Golgi apparatus lysosome nucleus
mitochondrian
Some human cells are restricted to aerobic respiration to recycle NADH and FADH2. If these cells are deprived of oxygen, then _____. glycolysis could still continue indefinitely proton gradient formation would continue, but ATP synthase function would stop oxidative phosphorylation would come to a halt because there wouldn't be any oxygen to "pull" the electrons down the transport chain ATP production would continue because the cell would perform fermentation
oxidative phosphorylation would come to a halt because there wouldn't be any oxygen to "pull" the electrons down the transport chain
The conversion of CO2 and H2O into organic compounds using energy from light is called fermentation. glycolysis. cellular respiration. photosynthesis.
photosynthesis
Bacteria have no membrane-enclosed organelles. However, some still generate ATP through cellular respiration. Where is the electron transport chain found in these organisms?plasma membrane mitochondria cytoplasm nucleoid region
plasma mebrane
Using the ATP generated during cellular respiration, the intermediates of glycolysis and the citric acid cycle can be siphoned off and used to _____. generate the ADP that is used to power biosynthetic pathways provide virtually all the heat needed to maintain body temperature power the biosynthesis of amino acids, fats, and sugars 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
power the biosynthesis of amino acids, fats, and sugars
In oxidative phosphorylation, electrons are passed from one electron carrier to another. The energy released is used to _____. form ATP during glycolysis pump protons (H+) across the mitochondrial membrane generate large amounts of NADH and FADH2 synthesize carbon dioxide
pump protons (H+) across the mitochondrial membrane
The end products of the citric acid cycle include all of the following except ATP. FADH2. pyruvate. CO2.
pyruvate
After glycolysis but before the citric acid cycle, a carbon atom is added to pyruvate to make a four-carbon compound. glucose is split, producing two molecules of pyruvate. coenzyme A is cleaved off pyruvate. pyruvate is oxidized.
pyruvate is oxidized.
A muscle cell deprived of molecular oxygen will convert glucose to lactic acid to _____. transition into the citric acid cycle recycle NADH through fermentation gain energy through chemiosmosis gain 2 ATP through glycolysis
recycle NADH through fermentation
In eukaryotes, most of the high-energy electrons released from glucose by cell respiration _____. are used for synthesizing lactic acid reduce NAD+ to NADH, which then delivers them to the electron transport chain are used to form ATP by the citric acid cycle are bound to FAD to be sent through the process of oxidative phosphorylation
reduce NAD+ to NADH, which then delivers them to the electron transport chain
Muscle tissues make lactic acid from pyruvate so that you can _____.get rid of toxic pyruvate utilize the released CO2 regenerate (oxidized) NAD+ utilize the energy in pyruvate
regenerate (oxidized) NAD+
Glycolysis is the only stage of cellular respiration that _____. does not release carbon dioxide as a by-product requires ATP to make ATP does not require ATP to make ATP requires oxygen to function
requires ATP to make ATP
Most of the NADH that delivers high-energy electrons to the electron transport chain comes from _____. chemiosmosis the cytoplasm the citric acid cycle glycolysis
the citric acid cycle
A drug is tested in the laboratory and is found to create holes in both mitochondrial membranes. Scientists suspect that the drug will be harmful to human cells because it will inhibit glycolysis, the citric acid cycle, and oxidative phosphorylation the citric acid cycle, oxidative phosphorylation, and glycolysis oxidative phosphorylation, glycolysis, and the citric acid cycle glycolysis, oxidative phosphorylation, and the citric acid cycle
the citric acid cycle and oxidative phosphorylation.
Which of the following directly requires molecular oxygen (O2)? glycolysis the citric acid cycle the electron transport chain chemiosmosis
the electron transport chain
Sunlight is essential for the varied life on Earth. Sunlight provides energy to photosynthetic organisms by providing _____. the energy required to drive cellular respiration heat to leaves, which is converted to useful energy for work the energy necessary to power the rearrangement of chemical bonds heat to leaves, which is used to synthesize chloroplasts
the energy necessary to power the rearrangement of chemical bonds
The ATP synthase in a human cell gets energy for making ATP directly from _____. the flow of H+ through a membrane the movement of electrons through a series of carriers the oxidation of glucose the reduction of oxygen
the flow of H+ through a membrane
Where do the reactions of the citric acid cycle occur in eukaryotic cells? the mitochondrion the folds of the inner mitochondrial membrane the intermembrane space of the mitochondrion the cytoplasmic fluid
the mitochondrian
Some friends are trying to make wine in their basement. They've added yeast to a sweet grape juice mixture and have allowed the yeast to grow. After several days they find that sugar levels in the grape juice have dropped, but there's no alcohol in the mixture. The most likely explanation is that the mixture needs more sugar, because yeast need a lot of energy before they can begin to produce alcohol. the mixture needs less oxygen, because yeast only produce alcohol in the absence of oxygen. the mixture needs more oxygen, because yeast need oxygen to break down sugar and get enough energy to produce alcohol. the yeast used the alcohol as a carbon source.
the mixture needs less oxygen, because yeast only produce alcohol in the absence of oxygen.
The enzyme ATP synthase catalyzes the phosphorylation of ADP to form ATP. In eukaryotic cells, the energy needed for this endergonic reaction is derived from _____. the fermentation of pyruvate to form lactic acid the movement of FADH2 from the cytoplasm to the mitochondria the reduction of NAD+ to form NADH the movement of hydrogen ions across the mitochondrial membrane
the movement of hydrogen ions across the mitochondrial membrane
A child is born with a rare disease in which mitochondria are missing from skeletal muscle cells. However, the muscles still function. Physicians find that the muscles require extremely high levels of oxygen to function. the muscles contain large amounts of lactate following even mild physical exercise. the muscles contain large amounts of carbon dioxide following even mild physical exercise. the muscle cells cannot split glucose to pyruvate.
the muscles contain large amounts of lactate following even mild physical exercise.
A kilocalorie is defined as the quantity of food used to maintain normal bodily functions. the quantity of food consumed during a given type of exercise. the quantity of heat needed to raise the temperature of 1 kg of water by 1°C. the quantity of glucose needed to increase the body temperature by 1°C.
the quantity of heat needed to raise the temperature of 1 kg of water by 1°C.
Oxidative phosphorylation could not occur without glycolysis and the citric acid cycle, because _____.
these two stages supply the electrons needed for the electron transport chain
How do cells capture the energy released by cellular respiration? They store it in molecules of carbon dioxide. They produce ATP. The energy is coupled to oxygen. They produce glucose.
they produce ATP
Rotenone is a poison that blocks the electron transport chain. When it does so, glycolysis and the citric acid cycle eventually halt as well. This is because _____. they run out of NAD+ and FAD electrons are no longer available from the electron transport chain they run out of ATP the buildup of unused oxygen interferes with glycolysis and the citric acid cycle
they run out of NAD+ and FAD
Rotenone is a poison commonly added to insecticides. Insects exposed to rotenone will die because they will no longer be able to perform anaerobic respiration. they will no longer be able to produce adequate amounts of ATP. they will no longer be able to absorb water and will become dehydrated. high levels of fermentation products will build up in their bodies.
they will no longer be able to produce adequate amounts of ATP.
Using the ATP generated during cellular respiration, the intermediates of glycolysis and the citric acid cycle can be siphoned off and used _____. to provide virtually all the heat needed to maintain body temperature to 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 to power the biosynthesis of amino acids, fats, and sugars to generate the ADP that is used to power biosynthetic pathways
to power the biosynthesis of amino acids, fats, and sugars
A gram of fat oxidized by cellular respiration produces approximately _____ as much ATP as a gram of carbohydrate. half 4 times twice 10 times
twice
As a scientist employed by the FDA, you've been asked to sit on a panel to evaluate a pharmaceutical company's application for approval of a new weight loss drug called Fat Away. The company has submitted a report summarizing the results of their animal and human testing. In the report, it was noted that Fat Away works by affecting the electron transport chain. It decreases the synthesis of ATP by making the mitochondrial membrane permeable to H+, which allows H+ to leak from the intermembrane space to the mitochondrial matrix. This effect leads to weight loss. The method of weight loss described for Fat Away shows that the drug is acting as a metabolic uncoupler. redox promoter. feedback inhibitor. oxygen carrier.
uncoupler
Which of the following organisms can make organic molecules from water and carbon dioxide? mushroom bear wheat crayfish
wheat
Fat is the most efficient molecule for long-term energy storage even compared to carbohydrates because _____. with their numerous hydrogen atoms, fats provide an abundant source of high-energy electrons when compacted, fat occupies less volume than an equivalent amount of carbohydrate compared to carbohydrates, fat produces fewer toxic by-products when it is metabolized fats can directly enter the electron transport chain, the phase of respiration that produces the most ATP
with their numerous hydrogen atoms, fats provide an abundant source of high-energy electrons
Fat is the most efficient molecule for long-term energy storage, even compared to carbohydrates, because _____. with their numerous hydrogen atoms, fats provide an abundant source of high-energy electrons when compacted, fat occupies less volume than an equivalent amount of carbohydrate fats can directly enter the electron transport chain, the phase of respiration that produces the most ATP compared to carbohydrates, fat produces fewer toxic by-products when it's metabolized
with their numerous hydrogen atoms, fats provide an abundant source of high-energy electrons