Bio final exam chapter 6
How many kilocalories are captured in ATP from 1.5 moles of glucose? (see book section: Module 6.4) 420 kcal 275 kcal 138 kcal 550 kcal
420 kcal
In cellular respiration, which of the following is performed directly by the electron transport chain (or its components)? (see book section: Module 6.10) Oxygen gas is formed. A proton gradient is formed. ADP is phosphorylated to make ATP. Carbon dioxide is formed.
A proton gradient is formed.
Open Hint for Question 27 in a new window What happens to the energy that is given up by electrons as they move through the electron transport chain? (see book section: Module 6.10) It pumps H+ through a membrane. It makes NADH and FADH2. It breaks down glucose. It oxidizes water.
It pumps H+ through a membrane.
What is the purpose of embedding the electron transport chain in the membrane of a cell? (see book section: Module 6.11) 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.
NAD+ is reduced, which then oxidizes an electron acceptor in the electron transport chain
Once the citric acid cycle has been completed, most of the usable energy from the original glucose molecule is in the form of _____. (see book section: Module 6.9) CO2 acetyl CoA NADH ATP
NADH
Consider the figure below. _____ is to a mitochondrion as _____ is to a chloroplast. (see book section: Module 6.1) Sunlight ... chemical energy O2 ... CO2 ATP ... CO2 Glucose ... O2
O2 ... CO2
When pyruvate is converted to acetyl CoA, _____. (see book section: Module 6.8) CO2 and coenzyme A are formed CO2 and NADH are formed CO2 and ATP are formed one turn of the citric acid cycle is completed
CO2 and NADH are formed
In the absence of oxygen, cells need a way to regenerate which compound? (see book section: Module 6.13) ethanol NAD+ carbon dioxide lactic acid
NAD+
Open Hint for Question 11 in a new window Where does glycolysis occur in a eukaryotic cell? (see book section: Module 6.6) within the intermembrane space of the mitochondrion in the cytoplasmic fluid in the mitochondria on the inner mitochondrial membrane
in the cytoplasmic fluid
Open Hint for Question 44 in a new window 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 _____. (see book section: Module 6.13) ATP carbon dioxide lactic acid ADP
lactic acid
Open Hint for Question 9 in a new window Which of the following best describes the electron transport chain? (see book section: Module 6.5) 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. Hydrogens are added to CO2 to make an energy-rich compound.
Electrons pass from one carrier to another, releasing a little energy at each step.
Of the metabolic pathways listed below, the only pathway found in almost all organisms is _____. (see book section: Module 6.6) the electron transport chain cellular respiration the citric acid cycle glycolysis
glycolysis
A gram of fat oxidized by cellular respiration produces approximately _____ as much ATP as a gram of carbohydrate. (see book section: Module 6.15) half 10 times 4 times twice
twice
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? (see book section: Module 6.13) 0 ATP 2 ATP 38 ATP 4 ATP
2 ATP
During glycolysis, a molecule of glucose is partially oxidized. What is the net gain of ATP and NADH for each glucose molecule? (see book section: Module 6.7) 4 ATP and 10 NADH 32 ATP and 10 NADH 2 ATP and 2 NADH 6 ATP and 10 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? (see book section: Module 6.9) 2 ATP, 4 NADH, and 0 FADH2 2 ATP, 4 NADH, and 2 FADH2 2 ATP, 2 NADH, and 0 FADH2 0 ATP, 0 NADH, and 0 FADH2
2 ATP, 4 NADH, and 0 FADH2
The energy production per glucose molecule through the citric acid cycle is _____. (see book section: Module 6.9) 38 ATP 4 ATP, 8 NADH 2 ATP, 6 NADH 2 ATP, 6 NADH, 2 FADH2
2 ATP, 6 NADH, 2 FADH2
Open Hint for Question 43 in a new window 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? (see book section: Module 6.12) 6 ATP 38 ATP 2 ATP 4 ATP
4 ATP
The overall efficiency of respiration is approximately _____. (see book section: Module 6.12) 94% 40% 0.50% 2%
40%
In preparing pyruvate to enter the citric acid cycle, which of the following steps occurs? (see book section: Module 6.8) Oxygen atoms are formed into oxygen gas. Pyruvate is reduced by oxidizing an NAD+ to an NADH. A compound called coenzyme A binds to a two-carbon fragment. Carbon dioxide must be present for pyruvate to enter the citric acid cycle. End of Question 18
A compound called coenzyme A binds to a two-carbon fragment.
Why is the citric acid cycle called a cycle? (see book section: Module 6.9) NADH is recycled in the electron transport chain. Acetyl CoA binds to oxaloacetate that is restored at the end of the cycle. Glucose is cycled around and resynthesized. NAD+ and FAD are recycled.
Acetyl CoA binds to oxaloacetate that is restored at the end of the cycle.
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 _____. (see book section: Module 6.6) ATP ... cytoplasm CO2 ... mitochondria glucose ... mitochondria water ... cytoplasm
CO2 ... mitochondria
Which of the following serves primarily as a hydrogen-atom carrier molecule in cells? (see book section: Module 6.9) RNA ATP FAD CO2
FAD
As shown below, an electron carrier, such as _____, acts as an energy-storage molecule when it is _____. (see book section: Module 6.5) FAD ... oxidized FAD ... reduced FADH2 ... reduced FADH2 ... oxidized
FADH2 ... reduced
A muscle cell deprived of molecular oxygen will convert glucose to lactic acid to _____. (see book section: Module 6.13) recycle NADH through fermentation gain 2 ATP through glycolysis gain energy through chemiosmosis transition into the citric acid cycle
The membrane is impermeable to H+.
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 _____. (see book section: Module 6.12) stored in FAD and NAD+ found in NADH and FADH2 lost as heat passed to the oxygen used in the electron transport chain
They are used to form water.
Through respiration, humans breathe in O2 and breathe out CO2. However, what would happen if we did not breathe in O2? (see book section: Module 6.12) We would not make enough ATP to meet our energy requirements We would not be able to perform lactic acid fermentation. We would not have enough enzymes to catalyze reactions. We would not be able to synthesize organic molecules from inorganic molecules.
We would not make enough ATP to meet our energy requirements
Besides sugars and fats, organisms can use other molecules as fuel for cellular respiration. When protein molecules are used, _____ are produced as waste. (see book section: Module 6.15) sugar molecules molecules of lactic acid amino groups fatty acids
amino groups
During aerobic respiration, molecular oxygen (O2) is used _____. (see book section: Module 6.12) at the end of electron transport chain to accept electrons and form H2O at the end of the citric acid cycle to cycle back to oxaloacetate between glycolysis and the citric acid cycle to split a carbon from pyruvate 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
Carbon monoxide is a toxic gas because it directly _____. (see book section: Module 6.11) changes the permeability of the membrane blocks the transfer of electrons to the final electron acceptor inhibits ATP synthase inhibits the oxidation of NADH
blocks the transfer of electrons to the final electron acceptor
A small amount of ATP is made in glycolysis _____. (see book section: Module 6.7) by the transport of electrons through a series of carriers using energy from the sun to perform photosynthesis 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)
by the transfer of a phosphate group from a fragment of glucose to ADP (substrate-level phosphorylation)
Which of the following is the source of the energy that produces the chemiosmotic gradient in mitochondria? (see book section: Module 6.10) cytochrome c ATP electrons ATP synthase
electrons
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 _____. (see book section: Module 6.3) NADH water ATP carbon dioxide
carbon dioxide
Where does most of the ATP produced in cellular respiration come from? (see book section: Module 6.12) lactic acid fermentation the citric acid cycle glycolysis chemiosmosis
chemiosmosis
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 _____. (see book section: Module 6.16) citrate ATP glucose glyceraldehyde-3-phosphate
citrate
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 _____. (see book section: Module 6.12) used to make water from hydrogen ions and oxygen used directly for energy stored as fat converted to heat
converted to heat
In a eukaryotic cell, the electron transport chain is precisely located in or on the _____. (see book section: Module 6.10) cristae of the mitochondrion cytoplasmic fluid intermembrane space of the mitochondrion plasma membrane
cristae of the mitochondrion
Where in bacterial cells does the citric acid cycle occur? (see book section: Module 6.6) ribosome plasma membrane mitochondrion cytoplasm
cytoplasm
What is the mechanism of action for the enzyme ATP synthase? ATP is formed _____. (see book section: Module 6.10) in the absence of chemiosmosis due to substrate-level phosphorylation due to the potential energy of a concentration gradient of hydrogen ions across a membrane from glucose in the absence of oxygen
due to the potential energy of a concentration gradient of hydrogen ions across a membrane
The function of cellular respiration is to _____. (see book section: Module 6.3) extract usable energy from glucose synthesize macromolecules from monomers reduce CO2 extract CO2 from the atmosphere
extract usable energy from glucose
The major (but not sole) energy accomplishment of the citric acid cycle is the _____. (see book section: Module 6.9) completion of substrate-level phosphorylation formation of NADH and FADH2 formation of CO2 formation of ATP
formation of NADH and FADH2
Fat is the most efficient molecule for long-term energy storage, even compared to carbohydrates, because _____. (see book section: Module 6.15) when compacted, fat occupies less volume than an equivalent amount of carbohydrate with their numerous hydrogen atoms, fats provide an abundant source of high-energy electrons 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
found in NADH and FADH2
In the equation shown below, during cellular respiration _____ is oxidized and _____ is reduced. (see book section: Module 6.12) glucose ... oxygen carbon dioxide ... water oxygen ... ATP ATP ... oxygen
glucose ... oxygen
During cellular respiration, glucose is oxidized. However, an intermediate, _____, can be siphoned off and used to synthesize fats. (see book section: Module 6.16) glucose glyceraldeyhyde-3-phosphate pyruvate ATP
glyceraldeyhyde-3-phosphate
What is the name of the process in which glucose is converted to pyruvate? (see book section: Module 6.7) glycolysis chemiosmosis fermentation oxidative phosphorylation
glycolysis
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 _____. (see book section: Module 6.7) glycolysis produces so little ATP that the drug will have little effect bacteria are facultative anaerobes; they usually don't need to perform glycolysis bacteria do not perform glycolysis human cells also perform glycolysis; the drug might also poison them End of Question 16
human cells also perform glycolysis; the drug might also poison them
Open Hint for Question 8 in a new window A molecule is oxidized when it _____. (see book section: Module 6.5) gains a hydrogen ion (H+) gains an electron loses a hydrogen ion (H+) loses an electron
loses an electron
In humans, oxygen and carbon dioxide are exchanged with the atmosphere via the _____. (see book section: Module 6.2) kidneys liver lungs pancreas
lungs
Open Hint for Question 1 in a new window Primarily, cellular respiration serves to _____. (see book section: Module 6.3) break down toxic molecules produce cell structures from chemical building blocks make ATP to power the cell's activities make food
make ATP to power the cell's activities
The electron transport chain is a series of electron carrier molecules. In eukaryotes, where can this structure be found? (see book section: Module 6.6) mitochondria rough endoplasmic reticulum plasma membrane smooth endoplasmic reticulum
mitochondria
The principal molecules involved in transporting electrons to the electron transport chain are composed of _____. (see book section: Module 6.5) fatty acids nucleotides sugars amino acids
nucleotides
Bacteria have no membrane-enclosed organelles. However, some still generate ATP through cellular respiration. Where is the electron transport chain found in these organisms? (see book section: Module 6.6) plasma membrane nucleoid region cytoplasm mitochondria
plasma membrane
Using the ATP generated during cellular respiration, the intermediates of glycolysis and the citric acid cycle can be siphoned off and used _____. (see book section: Module 6.16) 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 generate the ADP that is used to power biosynthetic pathways to power the biosynthesis of amino acids, fats, and sugars
recycle NADH through fermentation
In eukaryotes, most of the high-energy electrons released from glucose by cell respiration _____. (see book section: Module 6.9) reduce NAD+ to NADH, which then delivers them to the electron transport chain are used for synthesizing lactic acid are bound to FAD to be sent through the process of oxidative phosphorylation are used to form ATP by the citric acid cycle
reduce NAD+ to NADH, which then delivers them to the electron transport chain
Muscle tissues make lactic acid from pyruvate so that you can _____. (see book section: Module 6.13) get rid of toxic pyruvate regenerate (oxidized) NAD+ utilize the released CO2 utilize the energy in pyruvate
regenerate (oxidized) NAD+
Most of the NADH that delivers high-energy electrons to the electron transport chain comes from _____. (see book section: Module 6.9) glycolysis the citric acid cycle the cytoplasm chemiosmosis
the citric acid cycle
Which of the following directly requires molecular oxygen (O2)? (see book section: Module 6.12) glycolysis chemiosmosis the citric acid cycle the electron transport chain
the electron transport chain
The ATP synthase in a human cell gets energy for making ATP directly from _____. (see book section: Module 6.10) the movement of electrons through a series of carriers the flow of H+ through a membrane 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? (see book section: Module 6.6) the mitochondrion the folds of the inner mitochondrial membrane the cytoplasmic fluid the intermembrane space of the mitochondrion
the mitochondrion
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 _____. (see book section: Module 6.10) the movement of FADH2 from the cytoplasm to the mitochondria the fermentation of pyruvate to form lactic acid 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
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 _____. (see book section: Module 6.11) they run out of NAD+ and FAD they run out of ATP electrons are no longer available from the electron transport chain the buildup of unused oxygen interferes with glycolysis and the citric acid cycle
they run out of NAD+ and FAD