Molecular and Cellular Biology Midterm 2 Study Guide Part 3

Chapter 11 Online Homework In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules? - 4 - 3 - 1 - 2 - 5

- 3

Chapter 11 Online Homework The plants referred to as C3 and C4 plants get this designation based on the number of carbons in the first detectable product of carbon dioxide fixation. The C3 product is ________, whereas the C4 product is ________. - glycerol; malate - triose phosphate; oxaloacetate - 3-phosphoglycerate; malate - 3-phosphoglycerate; oxaloacetate - ribose; phosphoenolpyruvate

- 3-phosphoglycerate; oxaloacetate

Chapter 10 Online Homework Aerobic respiration generates up to ________ ATP molecules per glucose molecule. - 2 - 16 - 24 - 38 - 42

- 38

Chapter 10 Online Homework In prokaryotes, aerobic respiration generates ________ ATP molecules. - 2 - 15 - 0 - 42 - 38

- 38

Chapter 10 Online Homework The overall efficiency of aerobic respiration in eukaryotes is about - 10%. - 25%. - 55%. - 75%. - 100%.

- 55%.

Chapter 11 Online Homework How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose? - 6 - 4 - 8 - 10 - 2

- 6

Chapter 11 Online Homework Which of these equations best summarizes photosynthesis? - 6 CO2 + 6 H2O → C6H12O6 + 6 O2 - C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy - 6 CO2 + 6 O2 → C6H12O6 + 6 H2O - C6H12O6 + 6 O2 → 6 CO2 + 12 H2O - H2O → 2 H+ + 1/2 O2 + 2e-

- 6 CO2 + 6 H2O → C6H12O6 + 6 O2

Chapter 11 Online Homework Each of the following is part of the energy transduction from solar energy to chemical energy except - electron flow through an electron transport system. - an electrochemical proton gradient. - unidirectional proton pumping across a membrane. - light absorption by chlorophyll. - All are involved in the energy transduction.

- All are involved in the energy transduction.

Chapter 10 Online Homework Each of the following molecules is an electron carrier in the electron transport system except - iron-sulfur proteins. - iron-containing cytochromes. - flavoproteins. - coenzyme Q. - All of the above are electron carriers.

- All of the above are electron carriers.

Chapter 11 Online Homework Plastocyanin (PC) - is a mobile electron carrier. - carries only one electron at a time. - is functionally similar to plastoquinol. - carries electrons to PSI. - All of the above are true of PC.

- All of the above are true of PC.

Chapter 11 Online Homework For which of the following reasons should glucose NOT be considered a primary product of photosynthesis? - Starch is the storage form of fixed carbon. - The carbon fixation reactions fix one CO2 at a time, not six. - The first reduced sugar formed is 3-phosphoglyceraldehyde (3 carbons). - All of the answers are correct.

- All of the answers are correct.

Chapter 11 Online Homework Which of the following explains why photosystem units contain a high proportion of antenna pigments compared to reaction centers? - Antenna pigments allow more wavelengths of light and more photons to be captured, increasing the efficiency of light capture. - Antenna pigments contain rubisco. - Antenna pigments help reduce the reaction centers. - Antenna pigments split water.

- Antenna pigments allow more wavelengths of light and more photons to be captured, increasing the efficiency of light capture.

Chapter 10 Online Homework Pyruvate dehydrogenase is regulated by all of the following except - CO2. - AMP. - NADH. - acetyl CoA. - ATP.

- CO2.

Chapter 11 Online Homework The relationship between photosystem I (PSI) and photosystem II (PSII) is correctly described by which of the following statements? - PSI precedes PSII in photosynthesis. - Electrons are excited by PSI or PSII, but not both. - Chlorophyll molecules in the reaction centers of PSI and PSII are designated P700 and P680, respectively, to reflect the wavelengths of their light absorption maxima. - PSII was discovered before PSI. - Only PSI contains a special pair of chlorophyll a molecules.

- Chlorophyll molecules in the reaction centers of PSI and PSII are designated P700 and P680, respectively, to reflect the wavelengths of their light absorption maxima.

Chapter 11 Online Homework Where does the Calvin cycle occur? - A - C - E - B - D

- E

Chapter 10 Online Homework The number of ATPs per NADH generated by the electron transport system is higher than the number generated per FADH2 because __________. - FADH2 has a lower (less negative) redox potential than NADH does - FADH2 has a higher (more negative) redox potential than NADH does - electrons from FADH2 are not oxidized all the way to water - NADH is converted to NAD+, which increases the charge gradient for ATP synthesis

- FADH2 has a lower (less negative) redox potential than NADH does

Chapter 10 Online Homework Pyruvate dehydrogenase is allosterically inhibited by ATP. Consider the picture in part A. - High ATP levels indicate adequate energy supply, so it makes sense that the enzyme responsible for providing the TCA cycle with more ATP is shut down. - High ATP levels indicate low levels of CoA−SH, so it is reasonable to shut down the reaction that consumes it. - High ATP levels indicate low levels of NAD+, so it is reasonable to shut down the reaction that consumes it. - High ATP levels indicate adequate energy supply, so it makes sense that the enzyme responsible for providing the TCA cycle with more acetyl CoA substrate is shut down.

- High ATP levels indicate adequate energy supply, so it makes sense that the enzyme responsible for providing the TCA cycle with more acetyl CoA substrate is shut down.

Chapter 10 Online Homework The dehydrogenases that oxidize isocitrate, αα-ketoglutarate, and malate (reactions TCA-3, TCA-4, and TCA-8) are all allosterically inhibited by NADH.Consider the picture in part A. - High NADH levels mean adequate oxidized coenzymmean adequate levels of this oxidized coenzymee for the generation of more ATP, so it makes sense to shut down the catabolic machinery of the cell. - High NADH levelsmean adequate levels of this reduced coenzyme for the generation of more ATP, so it makes sense to shut down the catabolic machinery of the cell. - High NADH levels indicate low pH of the mitochondrial matrix, so it makes sense to shut down the metabolic pathway responsible for the formation of more H+ ions. - High NADH levels indicate high pH of the mitochondrial matrix, so it makes sense to shut down the metabolic pathway responsible for the formation of more H+ ions.

- High NADH levelsmean adequate levels of this reduced coenzyme for the generation of more ATP, so it makes sense to shut down the catabolic machinery of the cell.

Chapter 10 Online Homework Phosphofructokinase (Reaction Gly-3) is allosterically inhibited by citrate. - High citrate levels are indicative of a insufficient supply of acetyl CoA, so it is reasonable that the key regulatory enzyme of the pathway leading to pyruvate and acetyl CoA is increased in activity. - High citrate levels are indicative of a sufficient supply of acetyl CoA, so it is reasonable that the key regulatory enzyme of the pathway leading to pyruvate and acetyl CoA is decreased in activity. - High citrate levels are indicative of a sufficient supply of oxaloacetate, so it is reasonable that the key regulatory enzyme of the pathway leading to oxaloacetate is decreased in activity. - High citrate levels are indicative of a sufficient supply of isocitrate, so it is reasonable that the key regulatory enzyme of the pathway leading to isocitrate is decreased in activity.

- High citrate levels are indicative of a sufficient supply of acetyl CoA, so it is reasonable that the key regulatory enzyme of the pathway leading to pyruvate and acetyl CoA is decreased in activity.

Chapter 10 Online Homework Isocitrate dehydrogenase (Reaction TCA-3) is allosterically activated by ADP - High levels of ADP mean low levels of ATP, so it is to the advantage of the cell to activate the metabolic pathway responsible for coenzyme (FAD and NAD+) oxidation, which can in turn give rise to ATP synthesis by electron transport. - High levels of ADP mean high levels of ATP, so it is to the advantage of the cell to activate the metabolic pathway responsible for coenzyme (FAD and NAD+) reduction, which can in turn give rise to ATP synthesis by electron transport. - High levels of ADP mean high levels of ATP, so it is to the advantage of the cell to activate the metabolic pathway responsible for coenzyme (FAD and NAD+) oxidation, which can in turn give rise to ATP synthesis by electron transport. - High levels of ADP mean low levels of ATP, so it is to the advantage of the cell to activate the metabolic pathway responsible for coenzyme (FAD and NAD+) reduction, which can in turn give rise to ATP synthesis by electron transport.

- High levels of ADP mean low levels of ATP, so it is to the advantage of the cell to activate the metabolic pathway responsible for coenzyme (FAD and NAD+) reduction, which can in turn give rise to ATP synthesis by electron transport.

Chapter 10 Online Homework Pyruvate dehydrogenase kinase is allosterically activated by NADH. - High levels of NADH mean adequate levels of this reduced coenzyme for the generation of ATP, so it makes sense to convert PDH to the inactive (phosphorylated) form, which is what PDH kinase does. - High levels of NADH mean adequate levels of this oxidized coenzyme for the generation of ATP, so it makes sense to convert PDH to the active (phosphorylated) form, which is what PDH kinase does. - High levels of NADH mean adequate levels of this oxidized coenzyme for the generation of ATP, so it makes sense to convert PDH to the inactive (phosphorylated) form, which is what PDH kinase does. - High levels of NADH mean adequate levels of this reduced coenzyme for the generation of ATP, so it makes sense to convert PDH to the active (phosphorylated) form, which is what PDH kinase does.

- High levels of NADH mean adequate levels of this reduced coenzyme for the generation of ATP, so it makes sense to convert PDH to the inactive (phosphorylated) form, which is what PDH kinase does.

Chapter 10 Online Homework α-ketoglutarate dehydrogenase (Reaction TCA-4) is allosterically inhibited by succinyl CoA. Consider the picture in part A. - High levels of succinyl CoA signal low levels of CoA−SH, so it seems reasonable to shut down the reaction that consumes it. - High levels of succinyl CoA signal adequate levels of NADH, so it seems reasonable to shut down the anabolic machinery of the cell. - High levels of succinyl CoA signal adequate levels of α-ketoglutarate, so it is reasonable to decrease in activity an enzyme that is responsible for formation of α-ketoglutarate. - High levels of succinyl CoA signal adequate levels of TCA-cycle intermediates, so it seems reasonable to shut down further TCA cycle activity.

- High levels of succinyl CoA signal adequate levels of TCA-cycle intermediates, so it seems reasonable to shut down further TCA cycle activity.

Chapter 11 Online Homework What is the advantage to having various types of chlorophylls and accessory pigments for the photosynthetic process? - It allows light to be harvested specifically in a step-wise manner. - It allows for light in many wavelengths to be utilized for photosynthesis. - It shifts the equilibrium of photosynthesis toward the formation of products. - It allows for a variation in color amongst plants. - It allows light to be harvested specifically in a step-wise manner and it shifts the equilibrium of photosynthesis toward the formation of products.

- It allows for light in many wavelengths to be utilized for photosynthesis.

Chapter 11 Online Homework Each of the following statements accurately describes the Calvin cycle except - It involves ribulose-1,5-bisphosphate (RuBP). - Its products enter a variety of metabolic pathways including sugar and starch biosynthesis. - It is confined to the cytoplasm in plants and algae. - It is found in all oxygenic and most anoxygenic phototrophs. - Carbon dioxide is fixed by reduction to form organic sugars.

- It is confined to the cytoplasm in plants and algae.

Chapter 11 Online Homework Which of the following minerals are directly involved with light absorption in photosynthesis? - Zn - Na - Fe - Mg - Ca

- Mg

Chapter 11 Online Homework A house plant seems to be growing slowly and lacks its normal bright green color. You call a botanist for advice. She suggests that the plant may be deficient in magnesium (Mg2+). Why are these symptoms associated with Mg2+ deficiency? - Cytochromes require Mg2+ to function properly. - Lack of Mg2+ in the soil allows pathogenic bacteria to grow. - Mg2+ is an important component in chlorophyll. - Mg2+ is important in the structure of many amino acids. - Mg2+ is required before NADPH can function.

- Mg2+ is an important component in chlorophyll.

Chapter 11 Online Homework Your house plant is growing slowly and lacks its normal bright green color, so you call a botanist for advice. She suggests that the plant may be deficient in magnesium (Mg2+). Why are these symptoms associated with Mg2+ deficiency? - Lack of Mg2+ in the soil allows pathogenic bacteria to grow. - Mg2+ is an important component in chlorophyll. - Mg2+ is important in the structure of many amino acids. - Cytochromes require Mg2+ to function properly. - Mg2+ is a cofactor for NADPH function.

- Mg2+ is an important component in chlorophyll.

Chapter 10 Online Homework Why are mitochondria so prevalent in skeletal muscle? - Mitochondria are primarily involved in repairing damage accumulated during exercise. - More mitochondria are required in tissues where blood flow is restricted. - Mitochondria provide energy for muscle contraction. - Mitochondria produce energy anaerobically. - Mitochondria provide the muscle elasticity to contract.

- Mitochondria provide energy for muscle contraction.

Chapter 11 Online Homework Which of the following statements correctly characterizes the relationship between NADP+/NADPH and NAD+/NADH? - Both are used extensively during photosynthesis in oxygenic phototrophs. - NADP+/NADPH has an extra phosphate compared to NAD+/NADH. - Only NAD+/NADH is used to transport electrons and protons. - NADP+/NADPH is used primarily for catabolic reactions. - Neither are helpful to oxygenic phototrophs.

- NADP+/NADPH has an extra phosphate compared to NAD+/NADH.

Chapter 11 Online Homework After 3-PGA is phosphorylated, it is reduced by _____. - ATP - CO2 - NADP+ - ADP - NADPH

- NADPH

Chapter 11 Online Homework Which of the following molecules is the primary product of photosystem I? - NADPH - ATP - Carbon dioxide - Oxygen

- NADPH

Chapter 11 Online Homework Which of the following statements correctly describes cyclic electron flow pathways? - Both PSI and PSII are required. - Water molecules are split. - No exogenous electron source is required. - Proton gradients are never formed. - O2 is released.

- No exogenous electron source is required.

Chapter 11 Online Homework Which of the following statements is correct regarding cyclic photosynthetic pathways? - Both PSI and PSII are required. - Proton gradients are not formed. - Water molecules need to be split. - No exogenous electron source is required. - all of the above

- No exogenous electron source is required.

Chapter 10 Online Homework Each of the following statements about the citric acid cycle is true except - Acetate enters the citric acid cycle and joins a four-carbon acceptor molecule to form citrate. - Oxidation by transfer of electrons to coenzymes occurs at two steps. - Decarboxylation to release CO2 occurs at two steps. - Substrate-level phosphorylation generates ATP/GTP at one step. - The cycle involves the ordered activity of eight enzymes.

- Oxidation by transfer of electrons to coenzymes occurs at two steps.

Chapter 10 Online Homework Which of the following statements is not true of the TCA cycle? - Oxidation occurs at three steps in the TCA cycle. - FAD is an electron acceptor in the cycle. - ATP/GTP is generated at one point by substrate-level phosphorylation. - Acetate enters the TCA cycle and joins a four-carbon acceptor molecule to form citrate. - Decarboxylation occurs at two steps in the TCA cycle.

- Oxidation occurs at three steps in the TCA cycle.

Chapter 10 Online Homework The chemiosmotic model of ATP synthesis is based on several lines of experimental evidence. Which of the following statements is not correct experimental evidence to support the chemiosmotic model? - Uncoupling agents abolish both the proton gradient and ATP synthesis. - Electron transport causes protons to be pumped out of the mitochondrial matrix. - Oxidative phosphorylation does not require a membrane-enclosed compartment. - Artificial proton gradients established by addition of acid can drive ATP synthesis in the absence of electron transport. - The proton gradient established by electron transport has enough energy to drive ATP synthesis.

- Oxidative phosphorylation does not require a membrane-enclosed compartment.

Chapter 11 Online Homework The relationship between photosystem I (PSI) and photosystem II (PSII) is correctly described by which of the following statements? - The absorption maximum of PSI is 680 nm. - PSI absorbs only short wavelengths of light. - The absorption maximum of PSII is 700 nm. - PSI is designated P700, whereas PSII is designated P680. - Electrons are excited by PSI or PSII, but not both.

- PSI is designated P700, whereas PSII is designated P680.

Chapter 11 Online Homework Which process produces oxygen? - Cellular respiration - Photosynthesis

- Photosynthesis

Chapter 11 Online Homework Which of the following reactions ensures that the Calvin cycle can make a continuous supply of glucose? - Carbon fixation - Regneration of RuBP - Production of G3P - Production of 3-phosphoglycerate Submit

- Regneration of RuBP

Chapter 11 Online Homework Carbon fixation involves the addition of carbon dioxide to _____. - RuBP - G3P - NADPH - Rubisco - 3-PGA

- RuBP

Chapter 10 Online Homework During which of the following steps of the TCA cycle does substrate-level phosphorylation take place? - TCA-4 - TCA-6 - TCA-2 - TCA-3 - TCA-5

- TCA-5

Chapter 11 Online Homework The reactions of the Calvin cycle are NOT directly dependent on light, but they usually do NOT occur at night. Why? - Carbon dioxide concentrations decrease at night. - The Calvin cycle depends on ATP and NADPH, which are most readily available from the light reactions. - It is often too cold at night for these reactions to take place. - Plants usually open their stomata at night.

- The Calvin cycle depends on ATP and NADPH, which are most readily available from the light reactions.

Chapter 11 Online Homework Which set of reactions uses H2O and produces O2? - The light-dependent reactions - The light-independent reactions

- The light-dependent reactions

Chapter 11 Online Homework Which of the following statements best describes the relationship between the light-dependent and light-independent reactions of photosynthesis? - The light-dependent reactions produce ATP and NADPH, which are then used by the light-independent reactions. - The light-dependent reactions pass electrons through an electron transport chain to the light-independent reactions. - The light-dependent reactions produce carbon dioxide, which is then used by the light-independent reactions. - The light-independent reactions release energy, and the light-dependent reactions require energy. Submit

- The light-dependent reactions produce ATP and NADPH, which are then used by the light-independent reactions.

Chapter 11 Online Homework What is the importance of the light-independent reactions in terms of carbon flow in the biosphere? - The light-independent reactions turn glucose, a sugar, into CO2 gas. - The light-independent reactions turn CO2, a gas, into usable carbon in the form of sugars. - The light-independent reactions use CO2 to make ATP. - The light-independent reactions turn sugar into ATP for energy.

- The light-independent reactions turn CO2, a gas, into usable carbon in the form of sugars.

Chapter 10 Online Homework If pyruvate-2-14C14C (pyruvate with the middle carbon atom radioactively labeled) is provided to actively respiring mitochondria, most of the radioactivity will be incorporated into citrate. Trace the route whereby radioactively labeled carbon atoms are incorporated into citrate, and indicate where in the citrate molecule the label will first appear. - The middle carbon atom of pyruvate in the TCA cycle becomes the carboxyl carbon of acetate and hence the newly added (upper) carboxyl group in citrate. - The middle carbon atom of pyruvate in the TCA cycle becomes the carboxyl carbon of acetate and hence the newly added (middle) carbonyl group in citrate. - The middle carbon atom of pyruvate in the TCA cycle becomes the carboxyl carbon of acetate and hence the newly added (middle) carboxyl group in citrate. - The middle carbon atom of pyruvate in the TCA cycle becomes the carboxyl carbon of acetate and hence the newly added (upper) carbonyl group in citrate.

- The middle carbon atom of pyruvate in the TCA cycle becomes the carboxyl carbon of acetate and hence the newly added (upper) carboxyl group in citrate.

Chapter 10 Online Homework Why are mitochondria so prevalent in skeletal muscle? - They are needed to provide energy for muscle contraction. - They are needed to repair damaged tissue that accumulates during exercise. - Bones and muscles require a great deal of energy to prevent them from separating. - They give the muscle enough elasticity to contract. - The flow of blood is greatest in skeletal muscle.

- They are needed to provide energy for muscle contraction.

Chapter 11 Online Homework What is the biological significance of the light-independent reactions of photosynthesis? - They convert carbon dioxide to sugar. - They convert ATP to sugar. - They generate ATP and NADPH. - They make oxygen.

- They convert carbon dioxide to sugar.

Chapter 11 Online Homework Bacteria do not have organelles. How are they able to carry out photosynthesis? - They are parasites of plants that do have organelles. - 70S ribosomes function as photosystems. - They interact in a symbiotic relationship with eukaryotic plants. - They use their cell membrane to carry out photosynthesis. - DNA in the nucleoid captures solar energy.

- They use their cell membrane to carry out photosynthesis.

Chapter 11 Online Homework True or false? The light-dependent reactions of photosynthesis use water and produce oxygen. - True - False

- True

Chapter 11 Online Homework In a chloroplast, the stroma is - a connection between the grana. - the region between in the inner and outer membranes. - a stack of thylakoids. - a pore in the outer membrane. - a gel-like matrix between the inner chloroplast membrane and the thylakoid membrane.

- a gel-like matrix between the inner chloroplast membrane and the thylakoid membrane.

Chapter 11 Online Homework All of the following are true regarding anoxygenic photosynthesis except - NADPH is regenerated by photoreduction. - absorbed light energy is typically in the near ultraviolet and far red ranges of the light spectrum. - sulfide or thiosulfate can act as electron donors. - a water molecule is split. - it is a light-driven oxidation-reduction process.

- a water molecule is split.

Chapter 10 Online Homework Which of the following is not a product of the TCA cycle? - acetyl CoA - NADH - FADH2 - ATP - CO2

- acetyl CoA

Chapter 10 Online Homework Which of these enters the citric acid cycle? - pyruvate - NADH + H+ - glucose - acetyl CoA - G3P

- acetyl CoA

Chapter 10 Online Homework Which of these is NOT a product of the citric acid cycle? - FADH2 - ATP - acetyl CoA - NADH + H+ - CO2

- acetyl CoA

Chapter 10 Online Homework Each of the following is a product of the citric acid cycle except - FADH2. - NADH. - ATP. - acetyl CoA. - CO2.

- acetyl CoA.

Chapter 11 Online Homework Which of the following statements accurately describes the Calvin cycle? - In this process, carbon dioxide is reduced to organic sugars. - It occurs in the chloroplast stroma. - It is a carbon assimilation process. - The Calvin cycle is a means of carbon fixation. - all of the above

- all of the above

Chapter 11 Online Homework Having various types of chlorophylls and accessory pigments for the photosynthetic process - allows light to be harvested specifically in a stepwise manner. - allows for a variation in color among plants. - shifts the equilibrium of photosynthesis toward the formation of products. - increases the efficiency of the Calvin cycle. - allows many wavelengths of light to be captured to provide energy for photosynthesis.

- allows many wavelengths of light to be captured to provide energy for photosynthesis.

Chapter 10 Online Homework Because the TCA cycle is associated with degradation and synthesis, the pathway is said to be - anabolic. - amphipathic. - amphibolic. - bipolar. - catabolic.

- amphibolic.

Chapter 10 Online Homework Because the citric acid cycle links degradation and synthesis, the pathway is classified as - catabolic. - amphibolic. - anabolic. - amphipathic. - bipolar.

- amphibolic.

Chapter 11 Online Homework When a photon is absorbed by a pigment (light-absorbing molecule), such as chlorophyll, the energy of the photon is transferred to - D1 protein to activate PSII. - NADP+ to make NADPH. - ATP synthase to make ATP. - Plastocyanin to be passed on to PSI. - an electron to move it from a low to a high energy orbital.

- an electron to move it from a low to a high energy orbital.

Chapter 11 Online Homework Most reactions involving NADP+ are ________ reactions, whereas most reactions involving NAD+ are ________ reactions. - anabolic; both catabolic and anabolic - catabolic; anabolic - both catabolic and anabolic; catabolic - anabolic; catabolic - metabolic; anabolic

- anabolic; catabolic

Chapter 11 Online Homework NADP+ is the coenzyme of choice in ________ reactions, while NAD+ is the coenzyme of choice in ________ reactions. - catabolic; anabolic - anabolic; both catabolic and anabolic - both catabolic and anabolic; catabolic - metabolic; anabolic - anabolic; catabolic

- anabolic; catabolic

Chapter 10 Online Homework In comparing beta -oxidation to glycolysis, it can be said that __________. - beta-oxidation bypasses acetyl co-A - beta-oxidation produces more energy per carbon because all carbons go through the TCA cycle, whereas only two-thirds of carbons from glucose do - both occur in the cytosol - beta-oxidation releases carbon dioxide and glycolysis does not

- beta-oxidation produces more energy per carbon because all carbons go through the TCA cycle, whereas only two-thirds of carbons from glucose do

Chapter 11 Online Homework In a chloroplast, the stroma is the - cytochromes associated with the thylakoids. - central semifluid region. - region between in the inner and outer membranes. - connection between the grana. - stack of thylakoids.

- central semifluid region.

Chapter 11 Online Homework Which of the following initially traps solar energy in the process of photosynthesis? - triose phosphate - water - chlorophyll - NADP+ - ATP

- chlorophyll

Chapter 11 Online Homework The proplastids associated with giving flowers and fruits their distinctive colors are the - elaioplasts. - chromoplasts. - amyloplasts. - chloroplasts. - plastids.

- chromoplasts.

Chapter 10 Online Homework Of the following electron carriers of the electron transport system, which transfers protons in addition to electrons? - cytochrome a - cytochrome b - iron-sulfur proteins - iron-copper proteins - coenzyme Q

- coenzyme Q

Chapter 11 Online Homework Which of the following is not an essential feature of electron transfer from water to NADP+? - cytochrome b6/f complex - plastocyanin (PC) - photosystem I complex - coenzyme Q - photosystem II complex

- coenzyme Q

Chapter 11 Online Homework Each of the following is an essential feature of electron transfer from water to NADP+ except - plastocyanin (PC). - PSII. - cytochrome b6/f complex. - PSI. - coenzyme Q.

- coenzyme Q.

Chapter 10 Online Homework In electron transport, which respiratory complex is not involved in the flow of electrons from FADH2? - complex I - complex II - complex III - complex IV - all of the above

- complex I

Chapter 10 Online Homework When electrons flow through the electron transport system from NADH to oxygen, what is the sequence of molecules through which they move? - complex I, coenzyme Q, complex III, cytochrome c, complex IV, O2 - complex I, cytochrome c, complex III, coenzyme Q, complex IV, O2 - complex I, coenzyme Q, complex IV, cytochrome c, O2 - complex II, coenzyme Q, complex III, complex IV, O2 - complex I, coenzyme Q, complex III, complex IV, O2

- complex I, coenzyme Q, complex III, cytochrome c, complex IV, O2

Chapter 10 Online Homework Of the following sequences, which shows the correct molecules through which electrons flow when delivered to the electron transport system by NADH? - complex I, coenzyme Q, complex III, complex IV, oxygen - complex I, cytochrome c, complex III, coenzyme Q, complex IV, oxygen - complex I, coenzyme Q, complex IV, cytochrome c, oxygen - complex II, coenzyme Q, complex III, complex IV, oxygen - complex I, coenzyme Q, complex III, cytochrome c, complex IV, oxygen

- complex I, coenzyme Q, complex III, cytochrome c, complex IV, oxygen

Chapter 10 Online Homework In electron transport, each of the following respiratory complexes is involved in the flow of electrons from FADH2 to O2 except - complex III. - complex II. - complex IV. - complex I. - All are involved in the flow of electrons from FADH2.

- complex I.

Chapter 10 Online Homework In electron transport, which respiratory complex is not involved in the flow of electrons from NADH? - complex I - complex II - complex III - complex IV - all of the above

- complex II

Chapter 10 Online Homework Each of the following complexes pumps protons out of the matrix to generate the proton gradient except - complex II. - coenzyme Q. - complex I. - complex IV. - complex III.

- complex II.

Chapter 10 Online Homework In electron transport, each of the following respiratory complexes is involved in the flow of electrons from NADH to O2 except - complex III. - complex IV. - complex I. - complex II. - All are involved in the flow of electrons from NADH.

- complex II.

Chapter 10 Online Homework Proton gradients are generated by all of the following complexes except - coenzyme Q. - complex III. - complex I. - complex IV. - complex II.

- complex II.

Chapter 10 Online Homework Which of the numbered respiratory complexes is not correctly paired with its name? - complex I: NADH dehydrogenase complex - complex II: succinate-coenzyme Q oxidoreductase complex - complex III: coenzyme Q-cytochrome c oxidoreductase complex - complex IV: cytochrome c reductase complex - none of the above

- complex IV: cytochrome c reductase complex

Chapter 10 Online Homework Which of the following molecules is not a carrier of electrons in the electron transport system (ETS)? - coenzyme Q - copper-nickel compounds - iron-sulfur proteins - flavoproteins - cytochromes

- copper-nickel compounds

Chapter 10 Online Homework Of the carrier molecules in the electron transport chain, which has heme as part of its prosthetic group? - flavoproteins - iron-sulfur proteins - cytochromes - coenzyme Q - copper-containing cytochromes

- cytochromes

Chapter 11 Online Homework Biosynthesis of sucrose occurs in the - stroma thylakoids. - intermembrane space. - cytoplasm. - thylakoid lumen. - stroma.

- cytoplasm.

Chapter 11 Online Homework Biosynthesis of sucrose occurs in the - vacuole. - chloroplast intermembrane space. - stroma. - thylakoid lumen. - cytosol.

- cytosol.

Chapter 11 Online Homework Which two triose phosphates are produced during the Calvin cycle and are the starting points for starch and sucrose synthesis? - dihydroxyacetone phosphate and glyceraldehyde-3-phosphate - 3-phosphoglycerate and glyceraldehyde-3-phosphate - ribulose-1,5-bisphosphate and glycerol phosphate - dihydroxyacetone phosphate and glycerate-1,3-bisphosphate - 3-phosphoglycerate and ribulose-1,5-bisphosphate

- dihydroxyacetone phosphate and glyceraldehyde-3-phosphate

Chapter 11 Online Homework Which of the following enzymes represents the link between the light and dark reactions of photosynthesis? - rubisco - photosystem I - photosystem II - ferredoxin-NADP+ reductase

- ferredoxin-NADP+ reductase

Chapter 11 Online Homework Photoheterotrophs are best described as organisms that obtain energy to make ATP - and organic compounds from sunlight. - from some forms of chemicals. - from sunlight but cannot make organic compounds from CO2. - from organic compounds but use sunlight to produce carbon sources. - from organic compounds.

- from sunlight but cannot make organic compounds from CO2.

Chapter 10 Online Homework Of the following enzymes associated with the TCA cycle, which of the following enzymes is not under allosteric regulation? - malate dehydrogenase - isocitrate dehydrogenase - α-ketoglutarate dehydrogenase - pyruvate dehydrogenase complex - fumarate hydratase

- fumarate hydratase

Chapter 10 Online Homework Each of the following citric acid cycle enzymes is subject to allosteric regulation except - fumarate hydratase. - isocitrate dehydrogenase. - pyruvate dehydrogenase. - malate dehydrogenase. - α-ketoglutarate dehydrogenase.

- fumarate hydratase.

Chapter 11 Online Homework Which molecule in the Calvin cycle is used to synthesize starch and sucrose? - ribulose-1,5-bisphosphate - ribulose-5-phosphate - 3-phosphoglycerate - glyceraldehyde-3-phosphate - 1,3-bisphosphoglycerate

- glyceraldehyde-3-phosphate

Chapter 11 Online Homework The NADPH required for CO2 fixation is produced __________. - by the reduction of O2 - by cyclic photophosphorylation - by the hydrolysis of ATP - in direct proportion to the amount of O2 produced

- in direct proportion to the amount of O2 produced

Chapter 10 Online Homework In eukaryotes, pyruvate is converted to acetyl CoA - during passage through the mitochondrial outer membrane. - in the intermembrane space. - during passage through the inner mitochondrial membrane. - in the cellular cytosol. - in the mitochondrial matrix.

- in the mitochondrial matrix.

Chapter 10 Online Homework In eukaryotes, pyruvate is converted to acetyl CoA - when passing the mitochondrial cristae. - in the intermembrane space. - in the cellular cytosol. - in the mitochondrial matrix. - when passing through the mitochondrial outer membrane.

- in the mitochondrial matrix.

Chapter 10 Online Homework Thermogenin in the inner membrane of brown fat cell mitochondria does all of the following except - decrease ATP synthesis. - decrease the proton gradient. - increase ATP synthesis. - uncouple ATP synthesis from electron transport. - generate heat.

- increase ATP synthesis.

Chapter 10 Online Homework Electron transport and oxidative phosphorylation are metabolic functions of the __________ of the mitochondrion. - intermembrane space - inner membrane - outer membrane - matrix

- inner membrane

Chapter 11 Online Homework Plastocyanin (PC) - is a mobile electron carrier. - is also called plastoquinol. - carries only a single electron at a time. - is a mobile electron carrier and carries only a single electron at a time. - is a mobile electron carrier, it is also called plastoquinol and it carries only a single electron at a time.

- is a mobile electron carrier and carries only a single electron at a time.

Chapter 10 Online Homework β-oxidation - is a process used to oxidize fatty acids. - occurs in the cytoplasm. - is the second step in the oxidation of glucose. - lengthens fatty acids by addition of two carbons. - is a process used to digest some polysaccharides.

- is a process used to oxidize fatty acids.

Chapter 10 Online Homework β-oxidation - occurs in the cytoplasm. - is a process used to oxidize fatty acids. - is the second step in the oxidation of glucose. - is a process used to digest some polysaccharides. - is a process used to oxidize fatty acids and occurs in the cytoplasm.

- is a process used to oxidize fatty acids.

Chapter 10 Online Homework Which molecule is incorrectly matched with the number of carbon atoms it possesses? - malate-5 - acetyl group of acetyl CoA-2 - isocitrate-6 - citrate-6 - α-ketoglutarate-5

- malate-5

Chapter 10 Online Homework Which of the following molecules is incorrectly matched with the number of carbon atoms it possesses? - isocitrate; 6 - acetyl CoA; 2 - citrate; 6 - α-ketoglutarate; 5 - malate; 5

- malate; 5

Chapter 10 Online Homework As pyruvate is prepared for the TCA cycle, it undergoes a process of - CoQ reproduction. - reductive decarboxylation. - oxidative carboxylation. - oxidative decarboxylation. - reductive carboxylation.

- oxidative decarboxylation.

Chapter 10 Online Homework As pyruvate is prepared for the citric acid cycle, it undergoes a process of - reductive carboxylation. - oxidative carboxylation. - oxidative decarboxylation. - substrate level phosphorylation. - reductive decarboxylation.

- oxidative decarboxylation.

Chapter 11 Online Homework The ATP synthase complex associated with the thylakoid membrane - contains a CF1 proton channel and a CFo ATPase complex. - accepts electrons from PSI. - is identical to the FoF1 complex of mitochondria. - performs photophosphorylation in oxygenic phototrophs. - is a soluble enzyme complex peripherally associated with PSI.

- performs photophosphorylation in oxygenic phototrophs.

Chapter 11 Online Homework The ATP synthase complex in the thylakoid membrane - contains an embedded CF1 component and a protruding CFo component. - performs photophosphorylation in oxygenic phototrophs. - is identical to the FoF1 complex of mitochondria. - contains an assembly of hydrophobic polypeptides that function in ATP synthesis. - all of the above

- performs photophosphorylation in oxygenic phototrophs.

Chapter 11 Online Homework Which of the following products cannot be used in the Calvin cycle? - CO2 - ribulose-1, 5-bisphosphate - NADPH - 3-phosphoglycerate - phosphoglycolate

- phosphoglycolate

Chapter 11 Online Homework Based on the comparisons of anoxygenic and oxygenic photosynthesis, the entry of oxygen into the atmosphere is most directly attributed to - PSI activity. - Q cycle activity. - Hatch - Slack pathway activity. - photophosphorylation. - Calvin cycle activity.

- photophosphorylation.

Chapter 11 Online Homework The process by which photosynthetic organisms use light energy for ATP production is known as - photosynthesis. - photoligase - phototaxis. - photophosphorylation. - photorespiration.

- photophosphorylation.

Chapter 11 Online Homework The process by which photosynthetic organisms use light energy for ATP production is known as - photosynthesis. - photophosphorylation. - photorespiration. - phototaxis. - photoreduction.

- photophosphorylation.

Chapter 11 Online Homework Plastoquinol transfers electrons from - cytochrome b6/f to plastiquinone. - cytochrome b6/f complex to coenzyme Q - water to photosystem II. - photosystem II to photosystem I. - light harvesting complex II to photosystem II.

- photosystem II to photosystem I.

Chapter 11 Online Homework Which is the correct order of flow of electrons through the thylakoid membrane during energy transduction reactions? - cytochrome complex, photosystem I, photosystem II - cytochrome complex, photosystem II, photosystem I - photosystem II, cytochrome complex, photosystem I - photosystem II, photosystem I, cytochrome complex

- photosystem II, cytochrome complex, photosystem I

Chapter 11 Online Homework Based upon the comparisons of anoxygenic and oxygenic photosythesis, the entry of oxygen into the atmosphere is most directly attributed to - photoreactivation. - bacteriorhodopsin. - photosystem I. - photosystem II. - the Calvin cycle.

- photosystem II.

Chapter 11 Online Homework Which of the following is not an accessory pigment used to absorb photons that cannot be captured by chlorophyll? - beta-carotene - phycochlorophyll - a phycobilin - lutein - phycocyanin

- phycochlorophyll

Chapter 11 Online Homework Which of the following pigments is found exclusively in red algae? - phycoerythrin - lutein - β-carotene - chlorophyll a - chlorophyll c

- phycoerythrin

Chapter 10 Online Homework In prokaryotes that carry out aerobic respiration, the ________ serves the same purpose as the inner mitochondrial membrane and the ________ serves the same purpose as the mitochondrial matrix. - ribosomes; plasma membrane - cytoplasm; cell wall - cytoplasm; plasma membrane - cytoplasm; nucleoid - plasma membrane; cytoplasm

- plasma membrane; cytoplasm

Chapter 11 Online Homework Which process in photosynthesis will be most directly compromised by inhibition of the cytochrome b6f complex? - NADP+ reduction - proton pumping - water splitting - carbon dioxide fixation

- proton pumping

Chapter 11 Online Homework The endosymbiotic theory states that mitochondria originated from - a routine step in evolution. - the fusion of several prokaryotes. - the slow evolution of various organelles over millions of years, particularly during the time of the dinosaurs. - purple bacteria entering and remaining in the cytoplasm of another cell. - a long, intense period of lightning.

- purple bacteria entering and remaining in the cytoplasm of another cell.

Chapter 10 Online Homework Pyruvate is converted to acetyl CoA by a unique enzyme known as - multiplex enzyme system. - pyruvate decarboxylase. - pyruvate dehydrogenase complex. - pyruvate CoA transferase. - transitionase system.

- pyruvate dehydrogenase complex.

Chapter 10 Online Homework Pyruvate is converted to acetyl CoA through the action of - pyruvate dehydrogenase complex. - citrate synthase. - pyruvate decarboxylase. - aconitase. - pyruvate CoA transferase.

- pyruvate dehydrogenase complex.

Chapter 11 Online Homework The transfer of energy directly from a photoexcited electron in a pigment molecule to another electron in an adjacent pigment molecule occurs by - photorespiration. - resonance energy transfer. - photochemical reduction - photoexcitation. - photophosphorylation.

- resonance energy transfer.

Chapter 11 Online Homework The transfer of energy from a photoexcited electron to another electron of an adjacent pigment molecule is known as - quantum leap. - photoexcitation. - resonance energy transfer. - photophosphorylation. - photorespiration.

- resonance energy transfer.

Chapter 10 Online Homework Multiple protein complexes associated with the cellular respiration are known as - synthesomes. - chemiosmotic coupling complexes. - Fe-S centers. - Q cycles. - respirasomes.

- respirasomes.

Chapter 11 Online Homework NADPH contains the pentose sugar ________ and the nitrogenous base ________. - deoxyribose; cytosine - glucose; thymine - ribose; adenine - deoxyribose; nicotinamide - ribose; nicotinamide

- ribose; adenine

Chapter 11 Online Homework In the Calvin cycle, the enzyme that catalyzes the capture of carbon dioxide and the formation of 3-phosphoglycerate is - phosphoribulokinase. - glyceraldehyde-3-phosphate dehydrogenase. - triose phosphate isomerase. - phosphoglycerokinase. - ribulose bisphosphate carboxylase/oxygenase (rubisco).

- ribulose bisphosphate carboxylase/oxygenase (rubisco).

Chapter 11 Online Homework The regeneration of what CO2 acceptor molecule allows for continuous carbon assimilation in the Calvin cycle? - ribulose-1,5-bisphosphate - 3-phosphoglycerate - dihydroxyacetone phosphate - glyceraldehyde-3-phosphate - glycerate-1,3-bisphosphate

- ribulose-1,5-bisphosphate

Chapter 11 Online Homework In the Calvin cycle, the enzyme that catalyzes the capture of carbon dioxide and the formation of 3-phosphoglycerate is - ferredoxin-NADP+ reductase. - phosphoglycerokinase. - glyceraldehyde-3-phosphate dehydrogenase. - triose phosphate isomerase. - ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco).

- ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco).

Chapter 11 Online Homework Continuous carbon assimilation in the Calvin cycle is made possible by the regeneration of - glycerate-1,3-bisphosphate. - 3-phosphoglycerate. - ribulose-1,5-bisphosphate. - dihydroxyacetone phosphate. - glyceraldehyde-3-phosphate.

- ribulose-1,5-bisphosphate.

Chapter 11 Online Homework Carbon dioxide generally enters the plant through pores called - stomata. - the cuticle. - bacteriochlorophylls. - connexons. - mesophyll.

- stomata.

Chapter 11 Online Homework The Calvin cycle occurs in the ________ region of the chloroplast. - thylakoid membrane - grana - outer membrane - stroma - thylakoid lumen

- stroma

Chapter 11 Online Homework The Calvin cycle occurs in the chloroplast - thylakoid lumen. - grana. - stroma. - thylakoid membrane. - outer membrane.

- stroma.

Chapter 10 Online Homework In the citric acid cycle, ATP molecules are produced by _____. - photosynthesis - photophosphorylation - oxidative phosphorylation - cellular respiration - substrate-level phosphorylation

- substrate-level phosphorylation

Chapter 10 Online Homework NADH concentrations serve to regulate oxidative decarboxylation and the TCA cycle. Which of the following enzymes is not regulated by NADH? - succinate dehydrogenase - malate dehydrogenase - α-ketoglutarate dehydrogenase - pyruvate dehydrogenase - isocitrate dehydrogenase

- succinate dehydrogenase

Chapter 10 Online Homework High NADH concentration regulates pyruvate oxidative decarboxylation and the citric acid cycle by allosterically inhibiting interacting with each of the following enzymes except - succinate dehydrogenase. - malate dehydrogenase. - isocitrate dehydrogenase. - α-ketoglutarate dehydrogenase. - pyruvate dehydrogenase.

- succinate dehydrogenase.

Chapter 10 Online Homework The sequential process of fatty acid catabolism to acetyl CoA is called - the oxidative phosphorylation pathway. - the citric acid cycle. - the β-oxidation pathway. - the Cori cycle. - the glyoxylate cycle.

- the β-oxidation pathway.

Chapter 10 Online Homework In brown fat, ________ present in the inner mitochondrial membrane uncouples ATP synthesis from electron transport in infants and other newborn mammals. - coenzyme A - respirasomes - fluorocitrate - submitochondrial particles - thermogenin

- thermogenin

Chapter 10 Online Homework When one pyruvate is oxidized, the products created specifically by the TCA cycle are __________. - oxygen, ATP, NADH, and FADH2 - two carbon dioxide, one ATP, three NADH, and one FADH2 - oxygen, ATP, NAD+, and FAD - three carbon dioxide, one ATP, four NADH, and one FADH2

- two carbon dioxide, one ATP, three NADH, and one FADH2

Chapter 10 Online Homework In the electron transport system, hydrogen atoms removed from NADH ultimately end up as part of __________. - carbon dioxide - NADH - water - ATP

- water

Chapter 11 Online Homework The light reactions of photosynthesis use _____ and produce _____. - carbon dioxide ... sugar - water ... NADPH - carbon dioxide ... oxygen - NADPH ... NADP+ - NADPH ... oxygen

- water ... NADPH

Chapter 10 Online Homework The sequential process of fatty acid catabolism to acetyl CoA is called - oxidative phosphorylation. - β-oxidation. - the glyoxylate cycle. - the Cori cycle. - hydrogenation.

- β-oxidation.