BIO311C Exam 3 (Biochemistry) Review
Catabolism of lipids and carbohydrates can results in the formation of _________, which enters the Krebs cycle. What is this product?
acetyl CoA
Based on the above graph, we can tell that compound-X is a/an
activator.
The frothing of beer is due to the CO2 released during
alcohol fermentation
When a chlorophyll molecule in photosystem I traps light, it loses an electron. In noncyclic electron flow this electron is replaced
by a donation from photosystem II
When the photophosphorylation occurs during light reactions, the pH of the thylakoid interior will ______________ compared to the equilibrium state during night time.
decrease
Enzyme activity can be regulated by all the following EXCEPT
degradation
Excessive use of antibiotics leads to the evolution of bacteria that become resistant to antibiotics. Suggest possible mechanism(s) by which bacteria will develop such inheritable resistance.
develop resistance by acquiring enzyme that will detox the antibiotic
Calvin cycle needs ATP because it is a/an ___________________ process.
endergonic
The primary function of light energy in photosynthesis is to ____________________ .
excite electrons in the reaction center chlorophyll.
CH4 + 2O2 --> CO2 + 2H2O + 160 kCal/mol energy is an example of a/an
exothermic reaction
Acetoacetate synthase is a key regulatory enzyme in the beginning of the valine biosynthetic pathway. When valine accumulates above a specific concentration, it inhibits the activity of acetoacetate synthase. The mechanism of action of valine is
feedback regulation
What is an example of a reaction that is spontaneous but results in a decrease of entropy within the system?
freezing in winter
The reactions of the Calvin cycle require all of the following molecules EXCEPT
glucose
The rate limiting enzyme in Krebs cycle is __________.
isocitrate dehydrogenase
Fast-twitch muscle fibers under stress generate a quick burst of energy and regenerate NAD+ mostly through __
lactate fermentation
Enzymes are biological catalysts that can increase the rate of a biochemical reaction by
lowering the energy of activation
In C4 plants such as corn and sugarcane, carbon fixation takes place in the __________ cells, and then the CO2 is transferred as malic or aspartic acid to __________ cells where carbon dioxide is released for entry into the Calvin cycle.
mesophyll; bundle sheath
Citrate binds to the regulatory site of the key regulatory enzyme PFK to inhibit Glycolysis whereas the substrates bind to the catalytic site that is different from the regulatory site. This effect of citrate is an example of _____________
non-competitive inhibition
Both NAD+ and FAD are
organic cofactors
The metabolic process most closely associated with intracellular membranes is __
oxidative phosphorylation
More free energy is released during the Krebs cycle than during glycolysis, but only 2 moles of ATP is produced for each mole of glucose undergoing glycolysis. Most of the remaining free energy that is produced during the Krebs cycle is used to ____________________________.
reduce NAD+ and FAD.
Calvin cycle needs NADPH because it is a/an _____________________ process
reduction
In this reaction, NADH + Pyruvate NAD+ + Lactate, Pyruvate becoming Lactate, is a/an __________________ process and ___________ is the oxidizing or reducing agent.
reduction.... NADH ...reducing
ATP is utilized in driving much cellular work because it
releases free energy during hydrolysis
Synthesis and transport of sugars out of leaf occur in __________ and through _____________ respectively in plants.
stroma and phloem
The reaction shown below is a/an ___________________ and it is catalyzed by _______."Creatine-phosphate + ADP Creatine + ATP"
substrate level phosphorylation.......kinase
When a suspension of algal cells is incubated in a flask in the presence of light and CO2 and then transferred to the dark, the release of oxygen stops. This reaction stops when the algal suspension is placed in the dark because _____________.
the reaction needs light
What are the benefits of photosynthesis to other organisms?
they are a primary source of energy and provide sugar and oxygen, helps make organic molecules, provides building materials for us.
Why do plants need water?
water is an essential reactant in photosynthesis, source of hydrogen to make sugar, and to absorb nutrients from the soil
Which of the expression correctly represents the free energy (ΔG) changes?
ΔG = ΔH - TΔS
A reaction was started with 40 mM substrate and it reached equilibrium in 2 hours. At equilibrium, the product concentration was 30 mM. Assuming a 1:1 ratio of substrate to product, what is the Keq in this reaction?
3, Since the product is formed from substrate the reactant or substrate concentration at equilibrium is the remainder of 40mM - 30mM = 10 mM. Hence the Keq = 30mM/10mM at equilibrium = 3
Phosphoglucomutase catalyzes the reaction glucose 6-phophate (G6P) to fructose 6-phosphate (F6P). You are starting the reaction in a test tube with the 0.8M substrate (G6P) and you let the reaction reach equilibrium. The product (F6P) concentration at equilibrium is 0.6M. There are no intermediates in this reaction and no products at the beginning. The Keq for this reaction is
3.0
ATP Hydrolysis yields 7.3 Kcal/mol free energy and it is coupled with many enzyme reactions that would not otherwise happen. Which of the following reaction can be coupled with ATP hydrolysis to become a spontaneous reaction? A reaction with a ΔG value of _______ Kcal/mol.
5.3
How many times the Calvin-Benson cycle should occur to make a single glucose molecule?
6, It takes 6 rounds of Calvin-Benson cycle for a single glucose molecule C6H12O6 to form.
Approximately what percentage of the ATP formed by the electron transport chain is produced by substrate-level phosphorylation? 0% 2% 10% 100% 38%
A
Carbon dioxide (CO2) is released during which of the following stages of cellular respiration? oxidation of pyruvate to acetyl CoA and the citric acid cycle glycolysis and the oxidation of pyruvate to acetyl CoA glycolysis and the citric acid cycle the citric acid cycle and oxidative phosphorylation
A
Fungi can defend against bacterial infection by making _______________________ Antibiotics Antibodies Starch DNA RNA
A
In addition to ATP, what are the products of glycolysis? NADH and pyruvate H2O, FADH2, and citrate CO2 and H2O CO2 and NADH CO2 and pyruvate
A
In chemiosmosis, what is the most direct source of energy that is used to convert ADP + ℗i to ATP? energy released from movement of protons down their electrochemical gradient through ATP synthase released as electrons flow through the electron transport system energy released from substrate-level phosphorylation energy released from ATP hydrolysis
A
Under anaerobic conditions, what carbon sources can be metabolized by yeast cells to produce ATP from ADP? glucose lactic acid ethanol pyruvate
A
What compound provides the reducing power for the Calvin cycle reactions? NADPH FADH2 ATP FAD CO2
A
What is the precursor to making fats and steroids? Acetyl CoA HMG CoA Pyruvate ATP NADH
A
Where are ATP synthase complexes located in a plant cell? thylakoid membranes and inner mitochondrial membranes thylakoid membranes only plasma membranes only inner mitochondrial membranes only thylakoid membranes and plasma membranes
A
Which of the following indicates a primary path by which electrons travel downhill energetically during aerobic respiration? glucose → NADH → electron transport chain → oxygen glucose → glycolysis → electron transport chain → NADH → ATP glucose → citric acid cycle → ATP → NAD+ glucose → pyruvate → acetyl CoA → ATP → oxygen glucose → glycolysis → citric acid cycle → NADH → ATP
A
Which of the following is a strong defense mechanism of plants to prevent grazing by animals? Making secondary metabolites that are toxic to animals Making antibiotics Making antibodies against animal grazing Making sugars and proteins for animals Making chitinase
A
Which of the following metabolic processes in eukaryotic cells will proceed normally whether oxygen (O2) is present or absent? glycolysis chemiosmosis electron transport the citric acid cycle oxidative phosphorylation
A
Which of the following process breaks down lipids to make Acetyl CoA? Beta Oxidation Oxidative phopshorylation Substrate level phosphorylation Photorespiration Krebs cycle
A
Which of the following statements best represents the relationships between the light reactions and the Calvin cycle? The light reactions provide ATP and NADPH to the Calvin cycle, and the Calvin cycle returns ADP, ℗i, and NADP+ to the light reactions. The light reactions supply the Calvin cycle with CO2 to produce sugars, and the Calvin cycle supplies the light reactions with sugars to produce ATP. The light reactions provide ATP and NADPH to the carbon fixation step of the Calvin cycle, and the Calvin cycle provides water and electrons to the light reactions. The light reactions provide the Calvin cycle with oxygen for carbon fixation, and the Calvin cycle provides the light reactions with sugars to produce ATP.
A
CAM plants can keep stomata closed in daytime, reducing water loss. This is possible because they __________. A) fix CO2 into organic acids during the night by PEP carboxylase B) use photosystems I and II during day and night. C) use the enzyme phosphofructokinase, to fix CO2 more effectively D) fix CO2 into sugars in the bundle-sheath cells. E) fix CO2 into pyruvic acid in the mesophyll cells.
A, PEP carboxylase has no O2 affinity and allows for C4 reactions to occur at night
The following reaction, with reference to FAD, is a __________________ process and FAD is a/an ______________(oxidizing or reducing) agent. FAD + X-H2 --> FADH2 + X A) reduction.... ...oxidizing B) oxidation........reducing C) reduction... ...reducing D) oxidation.... ...oxidizing E) oxidation ...oxidizing
A, This is the correct answer. FAD is gaining H+ and e- (being reduced by X-H2) and it is oxidizing X-H2
Which of the following is not an output of oxidative phosphorylation? A) CO2 B) ATP C) NAD+ D) FAD E) Water
A, WCO2 is released in acetyl CoA formation and Krebs cycle only and not during oxidative phosphorylation.
Which of the following are products of the Calvin cycle and are utilized in the light reactions of photosynthesis?
ADP, Pi, and NADP+
Which of the following is a precursor of steroids?
Acetyl CoA
Which of the following is not made as a net output during either alcohol or lactate fermentation?
Acetyl CoA
Which of the following molecule plays a central role in the metabolism of carbohydrates and lipids?
Acetyl CoA
Which of the following statements is true about the enzyme used in the above study?
All of the above
In an oxidation-reduction reaction, how is the reducing agent changed? It loses electrons and gains potential energy. It loses electrons and loses potential energy. It gains electrons and gains potential energy. It gains electrons and loses potential energy.
B
In liver cells, the inner mitochondrial membranes are about five times the area of the outer mitochondrial membranes. What purpose must this serve? It increases the surface area for the citric acid cycle. It increases the surface area for oxidative phosphorylation. It increases the surface area for substrate-level phosphorylation. It increases the surface area for glycolysis.
B
Photorespiration occurs when rubisco combines RuBP with which of the following molecules? H2O O2 glyceraldehyde 3-phosphate CO2
B
What is the primary function of the pigment molecules in a light-harvesting complex? to split water and release oxygen to the reaction-center chlorophyll to transfer light energy to the reaction-center chlorophyll to transfer electrons to the primary electron acceptor to synthesize ATP from ADP and ℗i
B
What is the primary role of oxygen in cellular respiration? to donate high energy electrons to the electron transport chain to serve as an acceptor for electrons and protons, forming water to serve as an acceptor for released carbon, forming CO2 to donate high energy electrons to NAD+, forming NADH
B
Which of the following molecules donates electrons directly to the electron transport chain at the highest energy level? ATP NADH FAD NAD+ FADH2
B
Yeast cells grown anaerobically can obtain energy by fermentation, which results in the production of ATP and lactate. ATP, CO2, and ethanol. ATP, NADH, and pyruvate. ATP, CO2, and lactate. ATP, CO2, and acetyl CoA.
B
Which of the following animal cells produce antibodies? A) A cells B) B cells C) T cells D) Stem cells E) Liver cells
B B cells gain memory of a particular antigen and develop antibodies.
Which of the following would slow down or inhibit key enzymes of Krebs cycle and glycolysis? A) Excess amount of ADP and Pi B) Excess amount of ATP C) Excess amount of NAD+ D) Excess amount of citrate E) Limited amount of FADH2.
B and D, Excess ATP would slow down the key enzymes in both process as that is a major output.
Which of the following process does not directly make any ATP? A) Glycolysis B) Acetyl CoA formation C) Krebs Cycle D) Oxidative phosphorylation E) Fermentation
B, Acetyl CoA formation only makes, CO2, and NADH besides Acetyl CoA. It does not produce any ATP during this process.
More free energy is released during the Krebs cycle than during glycolysis, but only 2 moles of ATP is produced for each mole of glucose undergoing glycolysis. Most of the remaining free energy that is produced during the Krebs cycle is used to _______________________ A) synthesize GTP. B) reduce NAD+ and FAD. C) release as heat. D) oxidize pyruvate. E) make ethanol.
B, Krebs cycle produces NADH and FADH2, which is used for oxidative phosphorylation
Which output of Glycolysis will enter the next step of Acetyl CoA formation? A) ATP B) Pyruvate C) ADP D) NADH E) Ethanol
B, Pyruvate enters mitochondrion and gets converted to Acetyl CoA
Overall, respiration is a/an____________________ and _______________________ A) oxidative........endergonic B) oxidative.....exergonic C) reductive.....endergonic D) reductive....exergonic E) endergonic.....redox process
B, Respiration is a break down process of extracting electrons from the food we eat and releasing free energy.
When we exercise for a long time without rest, the muscle cells become deprived of oxygen. Which of the following is not produced in a muscle cell under such conditions? A) NADH B) Ethanol C) ATP D) Pyruvate. E) Lactate.
B, We do not make ethanol because we cannot perform alcohol fermentation.
During photophosphorylation, the pH of the thylakoid interior will be _______________ A) higher than the pH of stroma since protons move into thylakoid B) lower than the pH of stroma since protons move into thylakoid space. C) same as the the pH of stroma since protons go in and out of thylakoid space D) higher than the pH of stroma since protons move into stroma from thylakoid space E) lower than the pH of stroma since protons move into the intermembrane space from stroma
B, protons are concentrated in the thylakoid space and the pH is lower than stroma
If plants are grown with H2O containing a radioactive isotope of oxygen (18O), subsequent analysis will show that 18O first appears in which of the following molecules produced by the plants? CO2 glyceraldehyde 3-phosphate (G3P) O2 ribulose bisphosphate (RuBP)
C
Living organisms increase in complexity as they grow, resulting in a decrease in the entropy of an organism. How does this relate to the second law of thermodynamics? The complexity is actually associated with greater disorder than the level of disorder associated with the organism at early stages of development. Living organisms are able to transform energy into entropy. As a consequence of growing, organisms cause a greater increase in entropy in their environment than the decrease in entropy associated with their growth. Living organisms do not obey the second law of thermodynamics, which states that entropy must increase with time.
C
Photosynthesis reactions are summarized below in the given equation. 6CO2 + 6H2O + light → C6H12O6 + 6O2 Which of the following changes will occur in this process with respect to free energy, enthalpy, and entropy. A) +ΔG, +ΔH, +ΔS B) +ΔG, -ΔH, +ΔS C) +ΔG, +ΔH, -ΔS D) -ΔG, +ΔH, +ΔS E) -ΔG, +ΔH, -ΔS
C
The ∆G for a particular enzyme-catalyzed reaction is -20 kcal/mol. If the amount of enzyme in the reaction is doubled, what will be the ∆G for the new reaction? -40 kcal/mol +20 kcal/mol -20 kcal/mol 0 kcal/mol +40 kcal/mol
C
Which of the following statements about enzyme-catalyzed reactions is true? Energy from ATP is required to activate the enzyme before it can catalyze the reaction. The free-energy change of the reaction is greater than when the same reaction occurs in the absence of an enzyme. The rate of the reaction is greater than when the same reaction occurs in the absence of an enzyme. The activation energy required for the reaction to proceed is greater than when the same reaction occurs in the absence of an enzyme.
C
Why might a severe fever result in death if it is not brought under control? It may destroy the primary structure of cellular enzymes. It may increase the rate of cellular chemical reactions. It may alter the tertiary and quaternary structures of cellular enzymes. It may result in consumption of excess ATP.
C
Zinc, an essential trace element for most organisms, is required in the active site of the enzyme carboxypeptidase in order for the enzyme to function properly. The zinc most likely functions as a(n) coenzyme derived from a vitamin. noncompetitive inhibitor of the enzyme. cofactor necessary for enzyme activity. allosteric activator of the enzyme. competitive inhibitor of the enzyme.
C
Most of the antibiotics are derived from ______________________ A) Algae B) Bacteria C) Fungi D) Plants E) Animals
C Penicillin, ampicillin and streptomycin all are derived from fungi.
Which of the following is an anabolic process that is endergonic and endothermic? A) ATP + H2O → ADP + Pi B) C6H12O6 + 6O2 → 6CO2 + 6H2O + energy C) CO2 + H2O + light → CH2O + O2 D) FADH2 → FAD + H2 E) CH4 + 2O2 → CO2 + 2H2O
C This is a summary of photosynthesis making carbohydrate from CO2 using light energy. Hence endergonic, endothermic and anabolic.
Vaccines protect the animals by ___________________________ A) Preventing viruses infecting the body B) Preparing enzymes to degrade the virus C) Helping to produce antibodies that will mark virus for degradation D) Mutating the human skin cells to resist viral infection E) Activate the killer T cells to kill the infections.
C Vaccines are proteins of viruses or weakened viruses that is recognized by the antibody producing cells. The antibodies made then recognize the real virus and mark them for degradation by macrophages or killer T cells.
Which of the following is an exergonic process that directly helps the endergonic process of ATP synthesis in oxidative phosphorylation? A) Acetyl CoA formation B) Ethanol fermentation C) Chemiosmosis D) Glycolysis E) Substrate level phosphorylation
C, ATP synthase actually uses the movement of the protons from the intermembrane space back into the matrix (chemiosmosis) as energy to allow it to make ATP from ADP and Pi.
If the Keq of a reaction is 10, when you increase the substrate concentration 2 fold, the Keq will _______________________ A) increase 2 fold also B) decrease by 2 fold C) stay the same D) increase by 20 fold E) decrease by 20 fold
C, Keq is a constant. When you increase substrate concentration, the product concentration will also increase proportionately if the conditions are optimal.
What is the purpose of oxygen in aerobic respiration? A) It is used to burn carbohydrates in each cell B) It is used to reduce the NAD+ and FAD C) Oxygen accepts electrons in the oxidative phosphorylation process. D) Oxygen combines with glucose and releases water E) Oxygen is neutral and hence works as a buffer
C, Oxygen is the ultimate acceptor of electrons and thus drive the entire process.
When a suspension of algae is incubated in a flask in the presence of light and CO2 and then transferred to the dark, the reduction of 3-phosphoglycerate to glyceraldehyde 3-phosphate is blocked. This reaction stops when the algae are placed in the dark because A) the reaction requires CO2. B) the reaction is exergonic. C) the reaction requires ATP and NADPH D) the reaction requires O2. E) chlorophyll is not synthesized in the dark.
C, These are made during the light reactions and are used in the Calvin cycle. ATP needed because the reaction is endergonic and NADPH is needed for reduction.
Which of the following statement is not true of glycolysis? A) ATP is used to prime the process B) ATP is made in this process. C) Acetyl CoA is an output of glycolysis D) NADH is produced E) Pi from cytoplasm is used to make ATP
C, This is a recall question. Know the products involved in glycolysis. Acetyl-CoA is formed after glycolysis from pyruvate oxidation. It is not an output of glycolysis.
All of the following are directly associated with photosystem II except __________________________.
CO2 fixation by RuBisCO.
Protists such as algae and diatoms are protected by _________________________
Cell wall, 1. Block the entry 2. Degrade the antibiotic 3. Mutation of target enzyme
Energy is stored in the form of ________ in the food we eat.
Covalent bonds
The complete reactions of cellular respiration in the presence of oxygen (C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + energy) result in which of the following? reduction of CO2 and oxidation of O2 oxidation of O2 and reduction of H2O reduction of C6H12O6 and oxidation of CO2 oxidation of C6H12O6 and reduction of O2
D
What is the primary function of the Calvin cycle? to produce oxygen by oxidizing water to produce carbon dioxide for use in the light reactions of photosynthesis to regenerate ATP for use in the light reactions of photosynthesis to produce simple sugars from carbon dioxide
D
Which of the descriptions below is an example of an exergonic reaction? formation of a peptide bond synthesis of ATP from ADP and ℗i a dehydration reaction between two monosaccharides to produce a disaccharide hydrolysis of glycogen to release glucose monomers
D
Which outputs of light reactions enter Calvin-Benson cycle? A) ATP B) NADPH C) O2 D) A and B E) A, B and C
D
Melting of ice at room temperature results in the following changes in free energy, enthalpy, and entropy. A) +ΔG, +ΔH, +ΔS B) +ΔG, -ΔH, +ΔS C) +ΔG, -ΔH, -ΔS D) -ΔG, +ΔH, +ΔS E) -ΔG, +ΔH, -ΔS
D Ice melting consumes energy from the surroundings to melt. Also, the energy in liquid water is more than the ice.
How does bacteria protect itself from viral infection? A) By having a strong cell wall, it blocks the entry of virus B) Bacterial cell capsule protects it from viral infection C) Plasma membrane will block the virus from entering the cell D) Restriction enzymes degrade the viral DNA once it enters the bacterial cell E) Using a viral protein that competes with any new viral infection.
D Restriction and methylation enzymes modify their own DNA to mark them and then degrade any foreign DNA if that enters
The first law of thermodynamics includes all the following except ___________________________ A) The total energy of the universe is constant B) Energy can neither be created nor destroyed C) Energy can be transferred or transformed D) Entropy increases in the universe with every energy transfer or transformation.
D This is part of second law of thermodynamics
When RuBisCO enzyme was modified to reduce the binding of oxygen to minimize photorespiration, the enzyme activity to fix CO2 to carbohydrate was also decreased. A possible explanation to this result is _______________. A) carbon fixation reaction requires O2. B) modified enzyme prefers O2 and not CO2. C) modified enzyme prefers CO2 and not O2. D) modified enzyme lost the binding to both O2 and CO2. E) carbon fixation reaction requires light and water.
D, CO2 decreases as it is fixed in the Calvin cycle. O2 increases as a result of light reactions (PS II). RUBISCO has the same active (binding) site for O2 and CO2. When you decrease O2 binding, you also reduce CO2 binding
When mice were fed with radioactive carbon in glucose (C6H12O6) all the 6 CO2 molecules will be released during which of the following process A) Krebs cycle and Oxidative phosphorylation B) Glycolysis and acetyl CoA formation C) Glycolysis and Krebs cycle D) Acetyl CoA formation and Krebs cycle E) Glycolysis and oxidative phosphorylation
D, Take a look at the respiration-flowchart from class. Acetyl CoA is formed from 2 pyruvates and in the process 2 CO2 molecules are released. During Krebs, 4 molecules are released.
Which of the following poison dissipate Δ [H+]? A) A poison that would inhibit ATP synthase B) A chemical that would inhibit citrate synthase C) A chemical that would block the substrate level phosphorylation D) A chemical that would make the inner mitochondrial membrane leaky to ions E) A chemical that mimics glucose but is not metabolized by hexokinase
D, The inner mitochondrial membrane is where the proton gradient is produced, which provides the energy for ATP synthase to make ATP. Making this leaky prevents the gradient from forming and no ATP can be made.
When does cyclic electron flow (at Photosystem I) occur instead of non-cyclic electron flow? A) When there is abundant ATP. B) When there is shortage of NADPH. C) When there is shortage of ATP. D) When there is abundance of NADPH. E) When there is equal amount of ATP and NADPH.
D, With a lot of NADPH, no need for non-cyclic photophosphorylation, plant can use cyclic electron flow to make ATP
In chemiosmosis in mitochondria, protons flow from the intermembrane space into the matrix. In what direction do protons flow during chemiosmosis in chloroplasts? from the stroma into the cytosol from the stroma into the thylakoid space from the intermembrane space into the stroma from the matrix into the stroma from the thylakoid space to into the stroma
E
What is the relation between exergonic and exothermic reactions? A) They are typically unrelated, but can be coupled with ATP hydrolysis B) Every exothermic reaction leads to a subsequent exergonic one C) Every exergonic reaction is also an exothermic one D) Both result in a reduction of entropy in the universe E) Exothermic reactions may be endergonic or exergonic processes
E
Plants can defend against grazers by producing ______________________ A) carbohydrates B) proteins C) lipids D) hormones E) secondary metabolites
E These are volatile and organic compounds that smell or taste bad.
Migratory birds store or carry limited amounts of stored energy or food but fly over long distances. Which of the following process is most utilized in such situations to make the most amount of ATP for their flying? A) Glycolysis B) Ethanol fermentation C) Lactate fermentation D) Krebs cycle E) Oxidative phosphorylation
E, 32-34 ATP made per glucose. So this will produce the most amount of energy for the bird. You should be able to calculate how much ATP is made with each of these processes.
The reaction shown below is a/an ___________________ and it is catalyzed by _______. Phosphoenolpyruvate + ADP --> Pyruate + ATP A) reduction.... kinase B) phosphorylation.....phosphatase C) oxidative phosphorylation.......ATP synthase D) substrate level phosphorylation.......ATP synthase E) substrate level phosphorylation.......kinase
E, ATP synthase adds inorganic phosphate (Pi) to ADP.
When one consumes excess amounts of carbohydrates, they gain weight and store excess energy as fat. Conversion of carbohydrates to fat will involve the intermediate _________. A) ATP. B) Starch. C) Citrate. D) NADH. E) Acetyl CoA.
E, Look at the respiration flowchart from class (on canvas). Excess carbohydrates results in more glycolysis so acetyl-CoA will build up. Instead of going on to Krebs, the acetyl-CoA can be converted into fatty acids and fat-storage.
Which of the following are essential for glycolysis? A) Glucose B) NAD+ C) ADP, Pi D) A and B E) A, B and C
E, Net inputs of glycolysis includes glucose, NAD+, ADP and Pi
The energy is stored in the form of ________ in the food we eat. A) acetyl CoA B) fructose C) proteins D) ATP E) covalent bonds
E, The covalent bonds provide the energy needed to produce ATP in the body that can be used as energy.
Suppose a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will have the most direct effect on which of the following processes? A) the absorption of light energy by chlorophyll B) the splitting of water C) the flow of electrons from photosystem II to photosystem I D) the reduction of NADP+ E) the synthesis of ATP
E, With no separation, no proton gradient will be generated, so ATP synthase will not function, inhibiting production of ATP
The outputs of oxidative phosphorylation that returns to Krebs Cycle are _____________ and _____________.
FAD and NAD+
The outputs of the Krebs cycle that transfer energy to the electron transport system are ___.
FADH2 and NADH
Each FADH2 produces less ATP when compared to NADH in oxidative phosphorylation because _________________
FADH2 gives electrons at a lower energy level to the ETC and hence makes less ATP.
What is directly responsible to generate the proton concentration gradient in photophosphorylation?
Flow of electrons from photosystem II to photosystem I Score: 0 out of 1
Which of the following process occurs under both aerobic and anaerobic conditions?
Glycolysis
The ultimate source of electrons used and oxygen released in the light reactions is _____.
H20
Which of the following is the key regulatory enzyme of steroid biosynthesis and is the target of cholesterol-lowering drug statins?
HMG CoA Reductase
Which of the following are common defense mechanisms among most of the organisms across the 3 domains?
Having a physical barrier such as cell wall and/or plasma membrane
An example of an exergonic and endothermic reaction is _______________.
Ice melting at room temperature
Which of the following is NOT TRUE of ribulose biphosphate carboxylase?
It catalyzes a phosphorylation reaction
Why visible light (wavelength of 400 to 700 nm) alone is useful in photosynthesis and not the high energy UV or long wavlength IR spectrucm of light?
It is the optimal energy level and safe range of visible light spectrum. Also, it is the most abundant wavelength of light.
Roundup herbicide is a competitive inhibitor of the enzyme EPSP-synthase in an amino acid biosynthesis pathway. Roundup can alter the
Km for its substrate(s).
The metabolic pathway that makes FADH2 and occurs in mitochondria is _
Krebs cycle
The C4 plants are efficient in using water because they _______________ _____________________________ (two words).
Minimize photorespiration.
RuBisCo is regulated by all the following except by______________.
NAD+
The outputs of glycolysis include ATP, ________ and _________.
NADH and pyruvate.
Which outputs that are/is common to glycolysis, acetyl CoA formation and Krebs cycle will enter oxidative phosphorylation?
NADH is a common output of both glycolysis and Krbs cycle whereas FADH2 is produced only in Krebs cycle.
The end products of glycolysis under aerobic conditions are __________.
NADH, ATP, and pyruvate
Which of the following enables the generation of Δ [H+]?
Oxidation of NADH and FADH2 resulting in electron transfer
Which of the following is the key regulatory enzyme in glycolysis inhibited by ATP and citrate?
Phosphofructokinase
What is a common mechanism to prevent any infection in all domains?
Physical barriers such as cell wall or capsule or skin.
Which of the following enzymes is probably the most abundant protein in the world that fixes atmospheric CO2 into organic molecules?
RuBP carboxylase/oxygenase (RuBisCO)
Where does the Calvin cycle of photosynthesis take place?
Stroma of the chloroplast
What is the general name of the process shown below and catalyzed by a kinase?
Substrate-level phosphorylation
How does the reduction of pyruvate to lactate during fermentation allow glycolysis to continue in the absence of oxygen? A) Water is formed during this reaction. B) This reaction is an endergonic reaction. C) This reaction is coupled to the oxidation of NADH to NAD+. D) This reaction is coupled to the formation of ADP and Pi. E) This reaction is coupled to the reduction of NAD+ to NADH.
Take a look at figure 9.9 on lactic acid fermentation. NADH is used as a reducing agent to reduce pyruvate to lactate. In the process, NAD+ is generated which can be used in glycolysis.
The action spectrum is broader than the absorption spectrum because ________________________________________________________.
The action spectrum is the result of all the pigments harvesting the light energy. The absorption spectrum depicts the relative amount of light absorbed by the individual pigments.
The second law of thermodynamics states that the energy
The energy transfer or transformation results in increased entropy
What is/are the main purpose(s) of respiration?
The main purpose of respiration is to make ATP. In addition, the metabolites generated in respiration are used to make other molecules needed by the organism.
Why do we eat?
We consume molecules by eating food. These molecules are broken down to make ATP and also to build our body.
