Bios 302 Final Exam
You need to make 385 ml of a buffer containing 0.6M MOPS, 150 mM sodium acetate, and 12mM EDTA. The formula weight for each is as follows: MOPS=209.26, sodium acetate= 82.03g, and EDTA= 292.24g. How many grams of EDTA do you need? Round to the nearest tenth of a gram.
(0.012 mols/1 L)(292.24 g/1 mol)(0.385 L) = 1.4 grams
You need to make 385 ml of a buffer containing 0.6M MOPS, 150 mM sodium acetate, and 12mM EDTA. The formula weight for each is as follows: MOPS=209.26, sodium acetate= 82.03g, and EDTA= 292.24g. How many grams of sodium acetate do you need? Round to the nearest tenth of a gram.
(0.15 mols/1 L)(82.03 g/1 mol)(0.385 L) = 4.7 grams
You want to make 2.5L of a solution containing 1x TBE, 0.2% SDS, and 7.5% ethanol. You have stock solutions with the following concentrations: 30x TBE, 10% SDS, and 95% ethanol. How many ml of 10% SDS are added to the final solution?
(0.2%)(2.5L)/10% = 0.05L or 50ml
You wish to determine what the redox reaction involving acetate and cytochrome a3+. The two half- reactions with their standard reduction potentials are as follows: Acetate + 2H++ 2e- ---> pyruvate E0= -0.70 2 cytochrome a3+ + 2e- ----> cytochrome a2+ E0= 0.385 What is the overall ΔEo of the redox reaction?
(0.385) - (-0.70) = 1.085
You need to make 385 ml of a buffer containing 0.6M MOPS, 150 mM sodium acetate, and 12mM EDTA. The formula weight for each is as follows: MOPS=209.26, sodium acetate= 82.03g, and EDTA= 292.24g. How many grams of MOPS do you need? Round to the nearest tenth of a gram.
(0.6 mols/1 L)(209.26 g/1 mol)(0.385 L) = 48.3 grams
You want to make 2.5L of a solution containing 1x TBE, 0.2% SDS, and 7.5% ethanol. You have stock solutions with the following concentrations: 30x TBE, 10% SDS, and 95% ethanol. How many ml of 30x TBE are added to the final solution?
(1x)(2.5L)/30x = 0.083L or 83ml
You want to make 2.5L of a solution containing 1x TBE, 0.2% SDS, and 7.5% ethanol. You have stock solutions with the following concentrations: 30x TBE, 10% SDS, and 95% ethanol. How many ml of 7.5% ethanol arcaded to the final solution?
(7.5%)(2.5L)/95% = 0.197L or 197ml
You want to make 2.5L of a solution containing 1x TBE, 0.2% SDS, and 7.5% ethanol. You have stock solutions with the following concentrations: 30x TBE, 10% SDS, and 95% ethanol. Assuming water is the solvent, how many ml of water are added to the final solution?
2.5 - (0.083 + 0.05 + 0.197) = 2.17L or 2170ml
Ras is a monomeric G-protien (GTPase). In its activated form, Ras promotes cellular proliferation. You have an opportunity to do some undergraduate research in a lab that uses a cell line that grows at an extremely slow rate. You don't want to spend all your free time in the lab, so you come up with an idea to increase the proliferation rate of this cell line by making a mutant version of this cell line. Which of the following mutations would you suggest to the principal investigator as a way to increase the proliferation rate of this cell line? A. A mutation that prevents cells from making the Ras GAP (GTPase activating protein) B. A mutation that decreases the affinity of Ras for GTP C. A mutation that increases the rate of GTP hydrolysis by Ras D. A mutation that prevents the Ras GEP (guanine nucleotide exchange factor) from being made E. A mutation that increases the affinity of Ras GDP
A . A mutation that prevents cells from making the Ras GAP
Which would you expect to find buried within the protein core? (look at Exam 1 Question 30)
A.
If keq=0.594 for a certain chemical reaction, what is the ΔG for that reaction? A. 0.32 B. 0.14 C. -0.14 D. -0.32 E. Cannot be determined
A. 0.32
You have discovered a new species of yeast. You have determined that this species has doublestranded DNA and that 13% of its total DNA is made up of Guanine. How much of its DNA is cytosine? A. 13% B. 26% C. 37% D. 74% E. Cannot be determined
A. 13%
Which strand is the lagging strand? (look Exam 3 Question 2) A. A. B. B.
A. A.
Which of the following statements regarding acetylation of histone tails is NOT true? A. Acetylated amino acids recruit enzymes containing chromodomains B. Lysine residues are typically the target of this modification C. This modification is catalyzed by enzymes known as HATs D. These modified amino acid residues lose their positive upon acetylation E. These acetylated amino acids recruit enzymes containing bromodomains
A. Acetylated amino acids recruit enzymes containing chromodomains
You have just joined a lab that studies a protein known as HIF- 1α. You have been tasked with identifying mitochondrial proteins that interact with HIF-1α. In what order would you perform the following techniques to achieve your objective? (Assume you have a commercially available antibody for HIF-1α) A. SDS-PAGE B. Tissue homogenization C. Mass spectrometry D. Affinity chromatography E. Differential centrifugation A. B, E, D, A, C B. C, A, D, E, B C. B, D, E, A, C D. A, B, C, D, E E. B, C, E, D, A
A. B, E, D, A, C
The nucleotide pictured above is? (look at Exam 1 question 18) A. Cytidine triphosphate B. Uridine triphosphate C. Thymidine triphosphate D. Deoxycytidine triphosphate E. Deoxythymidine triphosphate
A. Cytidine triphosphate
In their experiment proving DNA is the genetic material, Hershey and Chase relied upon the fact that radioactive phosphorous would be specifically incorporated into which biological polymer? A. DNA B. RNA C. Proteins D. Lipids E. Monosaccharides
A. DNA
The nucleotide from the previous question would be found in which biological macromolecule? (look Exam 2 question 24) A. DNA B. RNA C. Glycogen D. Phospholipid
A. DNA
What type of chemical reaction occurs when biological monomers are linked to a growing polymer? A. Dehydration/ Condensation reactions B. Fusion reactions C. Van der Waals reactions D. Hydrolysis reactions
A. Dehydration/ Condensation reactions
The image shows the interaction between which to nucleic acid bases? (look Exam 2 Question 33) A. Guanine and thymine B. Guanine and cytosine C. Guanine and adenine D. Adenine and thymine E. Adenine and cytosine
A. Guanine and thymine
Which of the following histones play a major role in the formation of the 30 nm fiber? A. Histone 1 B. Histone 2A C. Histone 2B D. Histone 3 E. Histone 4
A. Histone 1
The purine in the diagram from the previous question is in what form? (look Exam 2 Question 34) A. Keto B. Enol C. Amino D. Imino
A. Keto
What amino acid is dedicated in figure A? (look at Exam 1 Question 32) A. Leucine B. Valine C. Isoleucine D. Asparagine E. Lysine
A. Leucine
You have discovered a new species of yeast. You have determined that this species has doublestranded DNA and that 13% of its total DNA is made up of Guanine. A phrase that refers to the amino acid sequence of a polypeptide is: A. Primary structure B. Secondary strict C. Tertiary strict D. Quaternary structure
A. Primary structure
Indicate what aspects of protein biochemistry are used to achieve separation/ purification or analysis by the following techniques Affinity chromatography A. Protein binding sites B. Protein net charge C. Protein size D. Proteins size and net charge
A. Protein binding sites
DNA replication is ____________ A. Semi-conservative B. Dispersive C. Conservative D. Insurgent E. Random
A. Semi-conservative
You have isolated a MAPK mutant that no longer catalyzes the phosphorylation of a particular substrate and have determined that this mutant enzyme is no longer active because the conserved threonine residue necessary for MAPK activation has been mutated. Which of the following amino acids is LEAST likely to be the one in your mutant? A. Serine B. Valine acid C. Tyrosine D. Arginine E. Alanine
A. Serine
The statement: Energy cannot be created nor destroyed, but may be converted from one form to another, is known as? A. The 1st law of thermodynamics B. The 2nd law of thermodynamics C. The Gibb's free energy law D. The law of coupled reactions E. Occam's razor
A. The 1st law of thermodynamics
According to the rules of the VSEPR (valence shell electron pair repulsion) theory, an atom containing covalent bonds will adopt the geometry that minimizes: A. The repulsion between paired electrons B. The distance between bonded and non-bonded electrons C. The distance between its nucleus and the nucleus of the atom it is covalently interacting with D. The attraction between atoms involved in the covalent bonds E. Van der Waals interactions
A. The repulsion between paired electrons
Heterochromatin is highly condensed and transcriptionally inactive. A. True B False
A. True
Molecules that can be dissolved in water are hydrophilic, whereas those that cannot be dissolved in water are hydrophobic. A. True B. False
A. True
Protein phosphorylation is another way to alter the conformation of an enzyme and serves exclusively as a mechanism to decrease enzyme activity. A. True B. False
A. True
The amino acid depicted in the previous question can be phosphorylated. (look Exam 2 Question 16) A. True B. False
A. True
The amino acid depicted in the previous question can form a disulfide bond. (look Exam 2 Question 19) A. True B. False
A. True
The amino acid shown in the previous question is non polar. (look Exam 2 Question 21) A. True B. False
A. True
The molecules are isomers (look at Exam 1 Form B for image question 6) A. True B. False
A. True
You have discovered a new species of yeast. You have determined that this species has doublestranded DNA and that 13% of its total DNA is made up of Guanine. Covalent modification of proteins, such as phosphorylation and acetylation are irreversible. A. True B. False
B .False
What amino acid is depicted in figure C? (look at Exam 1 Question 34) A. Asparagine B. Arginine C. Histidine D. Lysine E. Glutamine
B. Arginine
Which strand is the leading strand? (look Exam 3 Question 1) A. A. B. B.
B. B.
The pyrimidine in question 33(Exam 2) is in what form? A. Keto B. Enol C. Amino D. Imino
B. Enol
The molecules are example of monosaccharides (simple sugars). (look Exam 1 Question 8) A. True B. False
B. False
The Keq for the reversible reaction Y ---> Z is 750. When the concentration of Y in a cell is 450 uM and the concentration of Z in the cell is 12500 uM, which of the following statements are true. A. Formation of Y is favored B. Formation of Z is favored C. The reaction in this cell is at equilibrium D. None of the above are true
B. Formation of Z is favored
This image shows the interaction between which two nucleic acid bases? (Look Exam 2 Question 23) A. Guanine and thymine B. Guanine and cytosine C. Guanine and adenine D. Adenine and thymine E. Adenine and cytosine
B. Guanine and cytosine
All of the following are essential features of eukaryotic chromosomes EXPECT? A. Origin of replication B. Intron C. Telomere D. Centromere
B. Intron
Which of the following techniques are NOT used to determine or analyze protein tertiary structure? A. X-ray diffraction B. Mass spectrometry C. Bioinformatics (amino acid sequence analysis) D. Nuclear magnetic resonance
B. Mass spectrometry
The electronegativity of C is 2.5 and that of At is 2.2. A bond between C and At will most likely be this type of bond. A. Ionic B. Non-polar covalent C. Polar covalent D Hydrogen E. Barry
B. Non-polar covalent
Indicate what aspects of protein biochemistry are used to achieve separation/ purification or analysis by the following techniques Ion exchange chromatography A. Protein binding sites B. Protein net charge C. Protein size D. Proteins size and net charge
B. Protein net charge
Substrate A binds to its enzyme with a dissociation constant of 6.8 x 10^-6 M, and substrate B bonds with a dissociation constant of 2.3 x 10^-8 M. Which substrate binds more tightly? A. Substrate A B. Substrate B C. Both have the same affinity for their respective enzymes D. Cannot be determined E. Occam's razor
B. Substrate B
One of the differences between velocity centrifugation or rate-zonal centrifugation and equilibrium centrifugation is that during rate-zonal centrifugation, all of your sample will pellet or sediment to the bottom of the centrifugation tube of you allow the centrifuge to run too long, whereas this will not happen in equilibrium centrifugation. A. The density of the gradient in which the sample is centrifuged is greater than the density of all the particles being centrifuged B. The density of the gradient in which the sample is centrifuged is lower than the density of all the particles being centrifuged C. The density of the gradient in which the sample is centrifuged is equal to the density of all of the particles being centrifuged D. Rate-zonal centrifugation is done in the absence of a density gradient
B. The density of gradient in which the sample is centrifuged is lower than the density of all the particles being centrifuged.
The amino acid shown here is: (look Exam 2 Question 21) A. Phenylalanine B. Tryptophan C. Proline D. Tyrosine E. Isoleucine
B. Tryptophan
Which amino acid is basic? (look at Exam 1 Question 28)
C.
The atomic number of phosphorous is 15. Phosphorous exists as a number of different isotopes. Two common isotopes are 31P, the stable, most abundant isotope, and 32P, an unstable, radioactive isotope. What is responsible for the difference between the two isotopes? A. 31P has 15 protons, whereas 32P has 17 protons B. 31P has 15 electrons, whereas 32P has 17 electrons C. 31P has 16 neutrons, whereas 32P has 17 neutrons D. 31P has 17 protons, whereas 32P has 15 protons
C. 31P has 16 neutrons, whereas 32P has 17 neutrons
You have discovered a new species of yeast. You have determined that this species has doublestranded DNA and that 13% of its total DNA is made up of Guanine. How much of its DNA is adenine? A. 13% B. 26% C. 37% D. 74% E. Cannot be determined
C. 37%
A molecule of DNA has the following sequences: 5' AATCGGCCA 3'. What is the sequence of the complementary stand of DNA? A. 5' TTAGCCGGT 3' B. 5' CCGATTAAC 3' C. 5' TGGCCGATT 3' D. 5' CAATTAGCC 3'
C. 5' TGGCCGATT 3'
What is a protein domain? A. A secondary structure like an α helix or β sheet B. A sequences of similar amino acids (polar, non polar) that mediate ligand binding C. A functional portion or module of a protein that folds into a stable characteristic 3-dimentional shape, independent of the rest of the protein D. The catalytic activity of an enzyme E. The compartment of a cell in which the protein resides
C. A functional portion or module of a protein that folds into a stable characteristic 3-dimentional shape, independent of the rest of the protein
Which of the following statements are TRUE? A. The active site of an enzyme usually occupies the entire enzyme surface B. Catalysis by enzymes never involves the formation of a covalent bond between an amino acid side chain and a substrate molecule C. Allosteric enzymes have two or more binding sites D. All of the above statements are true E. None of the above statements are true
C. Allosteric enzymes have two or more binding sites
Which amino acid(s) is/are polar? (look at Exam 1 Question 31) A. A, B, C B. A, C, D C. B, C, D D. A, D E. All of the above
C. B, C, D
Z-DNA is: A. The normal conformation of DNA in the cell B. DNA in a triple helix C. DNA with a left-handed double helix D. The conformation of dried DNA E. Only found in cells of organisms born on the planet Krypton
C. DNA with a left-handed double helix
In covalent bonds: A. Both atoms lose an electron B. One atom loses an electron while the other atom gain an electron C. Electrons are shared between two atoms D. Both atoms gain an electron E. The nuclei of the two atoms fuse together
C. Electrons are shared between two atoms
Which of the following statements is NOT true regarding enzymes. A. Enzymes speed up spontaneously occurring reactions B. Enzymes are very specific for their reaction C. Enzymes are used up during the reaction D. Enzymes lower the activation energy of a reaction E. Enzymatic reactions occur at the active site of the enzyme
C. Enzymes are used up during the reaction
What is the biochemical reaction that essentially makes DNA synthesis thermodynamically irreversible? A. Binding of dNTP in the active site of the enzyme B. Formation of the 5'-3' phosphodiester bond C. Hydrolysis of the released pyrophosphate into two molecules of Pi D. Participation of Mg++ ions in the active site
C. Hydrolysis of the release pyrophosphate onto two molecules of Pi
The polysaccharide in the picture to the right is a? (look Exam 1 Question 3) A. Nucleoside B. Aldose C. Ketose D. Fatty acid E. Zymolyase
C. Ketose
The three letter abbreviation for the pictured amino acid is: ( look Exam 2 Question 18) A. Ala B. Cys C. Met D. The E. Val
C. Met
A molecule that does not structurally resemble the substrate of a particular enzyme, is found to bind that enzyme at a location outside of the active site. When this molecules is added to an in vitro reaction containing the enzyme and its substrate, the km for the reaction is uncharged, but the max of the reaction is significantly decreased. The effect of this substance cannot be overcome by increasing the concentration of the substrate used in the reaction. The molecule describe is a? A. Semi-competitive inhibitor B. Uncompetitive inhibitor C. Non-competitive inhibitor D. Competitive inhibitor
C. Non-competitive inhibitor
Indicate what aspects of protein biochemistry are used to achieve separation/ purification or analysis by the following techniques Gel filtration chromatography A. Protein binding sites B. Protein net charge C. Protein size D. Proteins size and net charge
C. Protein size
Indicate what aspects of protein biochemistry are used to achieve separation/ purification or analysis by the following techniques SDS-PAGE A. Protein binding sites B. Protein net charge C. Protein size D. Proteins size and net charge
C. Protein size
To convert a liquid vegetable oil (remember, vegetable oils are composed of kinked lipids) to a solid, such as lard (composed of tightly packed lipids) one needs to: A. Use longer fatty acids B. Use shorter fatty acids C. Remove all double bonds between the carbon atoms in the fatty acids D. Add more double bonds between the carbon atoms in the fatty acids E. Replace one fatty acid with a polar head group
C. Remove all double bonds between the carbon atoms in the fatty acids
Elements are: A. Two atoms held together by ionic bonds B. The monomers used to build polypeptides C. Substances that cannot be broken down or interconverted by chemical means D. All of the above E. None of the above
C. Substances that cannot be broken down or interconverted by chemical means
An increase in the intracellular concentration of a positive allosteric regulator of a protein A. Has no effect on the activity of the protein B. Will decrease the activity of the protein C. Will increase the activity of the protein D. Causes the protein to be degraded
C. Will increase the activity of the protein
You wish to determine what the redox reaction involving acetate and cytochrome a3+. The two half- reactions with their standard reduction potentials are as follows: Acetate + 2H++ 2e- ---> pyruvate E0= -0.70 2 cytochrome a3+ + 2e- ----> cytochrome a2+ E0= 0.385 Write the full reaction
Cytochrome a3+ + pyruvate ----> cytochrome a2+ + acetate
Which amino acid above contains an amide group? (look at Exam 1 Question 27)
D.
C3H8 + 5O2 ---> 3CO2 + 4H20 ( look at exam 1 question 21) What is the ΔHrxn for this reaction? A. -2770 B. -1290 C. 1290 D. 2770
D. 2770
Why is the detergent SDS used in polyacrylamide gel electrophoresis? A. To denature proteins B. To impact a net negative charge to all sample proteins C. To ensure that proteins migrate according to their true size (length) D. All of the above E. None of the above
D. All of the above
Which of the following are examples van der Waals interactions? A. Weak interaction between two permanent dipoles B. An interaction between a permanent dipole and an induced dipole C. An interaction between an instantaneous dipole formed by a non-polar molecule D. All of the above are van der Waals interactions E. None of the above are van der Waals interactions
D. All of the above are van der Waals interactions
If the conserved Lys residue was changed to another amino acid, which mutation would have the best chance of producing functional enzyme? A. Glutamic acid B. Cysteine C. Tyrosine D. Arginine E. Alanine
D. Arginine
What amino acid is depicted in figure D? (look at Exam 1 Question 35) A. Glutamine B. Arginine C. Valine D. Asparagine E. Histidine
D. Asparagine
The reaction as written is: (look at Exam 1 Question 22) A. Geothermic B. Isothermic C. Endothermic D. Exothermic
D. Exothermic
Although all protein structures are unique, there are common structural building blocks that are referred to as regular secondary structures. Some proteins have α helices, some are β sheets, and still others have a combination of both. What makes it possible for proteins to have the common structural elements? A. Hydrogen bonding between R groups B. Specific amino acid sequences C. Hydrogen bonding between R groups and the polypeptide backbone D. Hydrogen bonds along the polypeptide backbone E. Hydrophobic core interactions
D. Hydrogen bonds along the polypeptide backbone
Which of the following statements are FALSE? A. Cancer ca result from the accumulation of mutations on somatic cells B. In the absence of DNA repair, genes are unstable C. The error rate of DNA replication is reduced both by proofreading by DNA polymerase and by DNA mismatch repair. D. Okazaki fragments are removed by a nuclease that degrades RNA E. All of the above are false
D. Okazaki fragments are removed by a nuclease that degrades RNA
Indicate what aspects of protein biochemistry are used to achieve separation/ purification or analysis by the following techniques 2D PAGE A. Protein binding sites B. Protein net charge C. Protein size D. Proteins size and net charge
D. Proteins size and net charge
This force or principle eliminates nearly 3/4 of all theoretically possible polypeptide conformations and is also the reason why almost all α helices are right handed. A. Van der Waals interactions B. London Dispersion Forces C. Electronegativity D. Steric Hinderance/ exclusion E. Sheldon Cooper Ambiguity Theory
D. Steric Hinderance/ exclusion
The one letter abbreviation for the pictured amino acid is: (look Exam 2 Question 16) A. F B. L C. S D. T E. Y
D. T
A major source of mutation during DNA replication is caused by the rapid switching of base configurations. The name of the process for the switching of bases between their different configurations is called (blank). A. Base flipping B. Reconciliation C. Oxidation D. Tautomerization
D. Tautomerization
Feedback inhibition involves interactions between: A. An enzyme and its substrate B. An enzyme and its product C. The substrate and the product but not the enzyme D. The product of a biochemical pathway and an enzyme near the beginning of the pathway E. The product of a biochemical pathway and an enzyme near the end of the pathway
D. The product of a biochemical pathway and an enzyme near the beginning of the pathway
Which amino acid is acidic (look at Exam 1 Question 29)
E.
Which of these types of interactions are responsible for stabilizing tertiary protein structure? A. Disulfide bonds B. Hydrogen bonds C. Electrostatic interactions D. Van der Waals ineractions E. All of the above
E. All of the above
Which of the following statements are FALSE? A. The specificity of an antibody molecule is contained exclusively in loops on the surface of the folded light-chain domain B. Nonycovalent bonds are too weak to influence the three-dimensional structure of macromolecules C. A large dissociation constant (Kd) indicates strong affinity between a ligand and a protein D. Upon centrifugation, smaller organelles sediment faster than larger ones E. All of the above are false
E. All of the above are false
Which of the following statements are true? A. An atomic nucleus contains protons and neutrons B. Both fatty acids and polysaccharides can be important energy stores in the cell C. Hydrogen bonds are weak and can be important energy, yet they contribute significantly to the specificity of interactions between macromolecules D. The number of neutrons determines whether the nucleus of an atoms is stable radioactive E. All of the above is true
E. All of the above is true
Which of the following chemical groups is present in these molecules? (look at Exam 1 Question 7) A. Hydroxyl B. Carbonyl C. Carboxyl D. Both a and b are present E. Both a and c are present
E. Both a and c are present
An amphipathic molecule is? A. Hydrophobic B. Hydrophilic C. Negatively charged D. Composed of both carbohydrates and nucleic acids E. Both hydrophilic and hydrophobic
E. Both hydrophilic and hydrophobic
The nucleotide shown here is: (Look Exam 2 Question 24) A. Adenosine diphosphate B. Guanosine diphosphate C. Urine diphosphate D. Deoxyguanosine diphosphate E. Deoxyadenosine diphosphate
E. Deoxyadenosine diphosphate
Based on the size and polarity (or lack thereof) of proline, insertion of which amino acid instead of proline in the substrate will have the best chance of interacting with the active site of the MAPK? A. Glutamine B. Glycine C. Alanine D. All of the above E. None of the above
E. None of the above
Which of the following statements are TRUE? A. The large and small subunit of an individual ribosome always stay together and never exchange partners B. Because the two strands of DNA are complementary, the mRNA of a given gene can be synthesized using either strand as a template. C. An mRNA may contain the sequence: ATTGACCCCGGTCAA D. The amount of protein present in a cell depends on iterate of synthesis, its catalytic, and iterate of degradation E. None of the above are true
E. None of the above are true
Which of the following statements are true? A. Proteins are remarkably diverse because each is made from a unique mixture of amino acids that are linked in random order B. The hydrophilic tails of phospholipid molecules are repelled from water C. DNA contains four different bases A, G, U, and C D. All of the above are true E. None of the above are true
E. None of the above are true
The nucleotide would most likely be found in which macromolecule? A. Triacylglycerol B. Glycogen C. Hemoglobin D. DNA E. RNA
E. RNA
All of the following except __________, are examples of non covalent interactions that help molecules adopt their final confirmation and promote intermolecular binding. A. Hydrogen bonds B. Electrostatic interactions C. Hydrophobic interactions D. Van der Waals interactions E. Random collision interactions
E. Random collision interactions
What amino acid is depicted in figure B? (look at Exam 1 Question 33) A. Leucine B. Lysine C. Threonine D. Serine E. Tyrosine
E. Tyrosine
You wish to determine what the redox reaction involving acetate and cytochrome a3+. The two half- reactions with their standard reduction potentials are as follows: Acetate + 2H++ 2e- ---> pyruvate E0= -0.70 2 cytochrome a3+ + 2e- ----> cytochrome a2+ E0= 0.385 Which of the half-reactions is more likely to gain electrons?
Reaction 2. Electrons move towards the reaction with the most positive standard reduction potential.
You wish to determine what the redox reaction involving acetate and cytochrome a3+. The two half- reactions with their standard reduction potentials are as follows: Acetate + 2H++ 2e- ---> pyruvate E0= -0.70 2 cytochrome a3+ + 2e- ----> cytochrome a2+ E0= 0.385 In the full reaction, which molecule is oxidized?
We know reaction one is going to be the oxidation reaction. However, it is given as a reduction reaction, so the products and the reactants need to be flipped. Therefore, pyruvate is being converted into acetate in the whole reaction. Pyruvate is the molecule being oxidized, not acetate.
You wish to determine what the redox reaction involving acetate and cytochrome a3+. The two half- reactions with their standard reduction potentials are as follows: Acetate + 2H++ 2e- ---> pyruvate E0= -0.70 2 cytochrome a3+ + 2e- ----> cytochrome a2+ E0= 0.385 In the full reaction, which molecule is reduced?
cytochrome a3+ is being reduced to cytochrome a2+
