Biochemistry CHEM 3500 Summer 2020 Exam 4 Name: ______________________________
Dr. Meades XXXXXXXXXXpossible points For questions 1-36, choose the one best answer (1 point each). You may keep the exam questions.
1.) A non-redox step in oxidation of fatty acids utilizes _____, concu
ently shortening the chain by _____ ca
on atoms.
A) NADH / 0 B) CoA / 2 C) H2O / 4 D) FADH2 / 2 E) H2O / 2 F) CoA / 3 G) FMN / 2
2.) Individuals with Andersen disease are unable to construct normal glycogen granules, instead forming the low water solubility molecules seen below, which precipitate in liver cells resulting in ci
hosis. Which enzyme is defective in these individuals?
A) glycogen synthase B) glycogen phosphorylase C) de
anching enzyme D)
anching enzyme
E) glycogenin F) phosphoglucose isomerase G) phosphorylase kinase
3.) The ester shown to the right is derived directly from methanol and what biochemical molecule? (Look at it carefully!)
A) citrate B) isocitrate C) succinate D) acetyl-CoA E) pyruvate F) oxaloacetate G) malate
4.) _____ transport mainly triacylglycerols in the blood from the liver to other cells.
A) chylomicrons B) VLDLs C) LDLs D) HDLs E) albumins F) insulins G) midichlorians
5.) The enzyme in the reaction depicted below belongs to what class? (Think about this one carefully!)
A) hydrolase B) isomerase C) lyase D) transferase E) ligase F) kinase XXXXXXXXXXG) oxidoreductase
6.) What is the name of the enzyme whose mechanism is depicted in the previous question?
A) enolase B) hexokinase C) aldolase D) pyruvate ca
oxylase E) aldolase F) RuBisCO G) ribose ca
oxylase
7.) The product formed in step 2 of the enzymatic reaction depicted above has become unstable primarily because _____.
A) the phosphate negative charges are now closer B) it now contains exactly three double bonds C) both A & B
D) it is now a β-keto acid E) it is a peroxide F) both D & E G) It is actually stable as an α-keto acid.
8.) The same enzyme can also utilize O2 in place of CO2 as the substrate by mistake. What makes the result of step 2 below unstable?
A) the phosphate negative charges are now closer B) it now contains exactly three double bonds C) both A & B
D) it is now a β-keto acid E) it is a peroxide F) both D & E G) It is actually stable as an α-keto acid.
9.) Which of the following is NOT involved in the synthesis of fatty acids?
A) acetyl-CoA B) NADPH C) biotin D) malonyl-CoA E) ACP F) CO2 G) All of the above ARE involved.
10.) Almost all of the nitrogen waste in the form of uric acid originates from _____.
A) CO2 B) inhaled N2 C) glucose D) purines E) fructose F) water G) pyrimidines
11.) The ultimate electron donor in photosynthesis is _____.
A) O2 B) H2O C) NADP+ D) NADPH E) CO2 F) N2 XXXXXXXXXXG) photons of light
12.) Which of the following amino acids is (are) strictly ketogenic upon degradation?
A) isoleucine B) leucine C) lysine D) valine E) tyrosine F) A & C only G) B & C only
13.) Partial oxidation of a 20:0 fatty acid could yield which of the following in addition to an acyl-CoA longer than 5 ca
ons?
14.) Complete oxidation of a 10:1Δ7 fatty acid yields which of the following?
15.) Complete oxidation of an 11:1Δ7 fatty acid yields which of the following in addition to propionyl-CoA (3:0)?
A) 4 acetyl CoA + 3 FADH2 + 4 NADH + 4 H+ B) 4 acetyl CoA + 4 FADH2 + 4 NADH + 4 H+
C) 5 acetyl CoA + 3 FADH2 + 4 NADH + 4 H+ D) 5 acetyl CoA + 4 FADH2 + 5 NADH + 5 H+
E) 6 acetyl CoA + 5 FADH2 + 6 NADH + 6 H+ F) 6 acetyl CoA + 5 FADH2 + 5 NADH + 5 H+
G) 6 acetyl CoA + 4 FADH2 + 5 NADH + 5 H+
16.) Which labeled monosaccharides are NOT removed as glucose-1-phoshate during glycogen degradation? (choose all that apply)
17.) Which TWO labeled monosaccharides could be acted upon by the
anching enzyme at this point in time?
18.) Which TWO labeled monosaccharides would be moved by the de
anching enzyme during glycogen degradation?
19.) Which TWO labeled monosaccharides were added by glycogenin during glycogen synthesis?
20.) Which of the following requisite metal ions or metal ion clusters is matched with the appropriate enzyme or pathway for which it serves as a cofactor?
A) Mn2+ - glycolysis B) Mg-Ca - photosynthesis C) Mo-Fe - RuBisCO D) Ti-Al - nitrogenase
E) Co2+ - cholesterol synthesis F) Fe-Ni - amino acid synthesis G) none of the above
21.) The major site for the action of acyl-CoA synthetase is which of the following?
A) inner mitochondrial mem
ane B) cytoplasm C) thylakoid mem
ane D) matrix
E) outer mitochondrial mem
ane F) stroma G) chloroplastic intermem
ane space
22.) In preparation for glycogen synthesis, the enzyme UDP-glucose pyrophosphorylase uses substrates containing _____ and _____ phosphates.
A) 0, 4 B) 1, 2 C) 2, 0 D) 1, 3 E) 2, 3 F) 3, 3 G) 2, 4
23.) Conversion of glycogen to glucose for export by a muscle cell involves which of the following enzymes?
A) phosphoglucose isomerase B) glucose-1-phosphorylase C) glycogen synthase D) aldolase
E) phosphoglycerate mutase F) glucose-6-phosphatase G) none of the above
24.) In the synthesis of a single cholesterol molecule, _____ ATP’s are utilized directly and _____ methyl groups are removed.
A) 3, 9 B) 9, 4 C) 10, 3 D) 17, 4 E) 18, 3 F) 6, 6 G) 36, 6
25.) Which of the following statements about β-oxidation of fatty acids is CORRECT?
A) Not all fatty acids must be activated to acyl-CoAs before entering the pathway.
B) Thiolytic cleavage releases acetyl-CoA and a shortened acyl-CoA in the final step of the cycle.
C) Both dehydrogenation reactions produce a C=O double bond.
D) Both dehydrogenation reactions use FAD as the electron acceptor.
E) For an odd-length fatty acid containing a C=C double bond, the location of the C=C double bond alternates even/odd.
F) For an even-length fatty acid containing a C=C double bond, the location of the C=C double bond alternates even/odd.
G) The first oxidation step is favorable because it eliminates an unstable α-keto a
angement.
26.) The reactions catalyzed by acyl-CoA synthetase and DNA polymerase share what feature driving them forward energetically?
A) loss of CO2 B) oxidation of NADPH C) elimination of an α-keto acid D) elimination of a β-keto acid
E) subsequent hydrolysis of pyrophosphate by pyrophosphatase F) hydrolysis of ATP G) all of the above
27.) The sources of the five nitrogen atoms of adenine in de novo synthesis can be described by which of the following?
A) 2 from glycine, 2 from glutamate, 1 from aspartate B) 2 from glutamate, 2 from aspartate, 1 from glycine
C) 3 from glycine, 2 from glutamate D) 1 from glycine, 1 from glutamate, 1 from aspartate, 2 from ammonia
E) 3 from aspartate, 1 from glutamate, 1 from glycine F) 4 from aspartate, 1 from glutamate
G) Adenine only has four nitrogen atoms, not five: 2 from glutamate, 1 from aspartate, 1 from glycine.
28.) The sources of the three nitrogen atoms of cytosine in de novo synthesis can be described by which of the following?
A) 2 from aspartate, 1 from glutamate B) 1 from aspartate, 2 from glutamine C) all 3 from aspartate
D) 1 from aspartate, 1 from glutamine, 1 from CO2 E) 3 from aspartate, 1 from glutamate, 1 from glycine
F) 1 from aspartate, 2 from ATP G) 2 from glutamate, 1 from glycine.
29.) _____ rounds of the Calvin cycle are required for the net production of a hexose sugar.
A) 1 B) 2 C) 4 D) 6 E) 9 F) 12 G) 36
30.) What is the equivalent functional component or space in mitochondria to the chloroplastic outer mem
ane?
A) mitochondrial outer mem
ane B) mitochondrial inner mem
ane C) mitochondrial intermem
ane space
D) matrix E) stroma F) thylakoid mem
ane G) none of the above
31.) During the linear flow of electrons through PS I and II, how many photons are needed per electron to complete the entire trip?
A) 0 B) 0.5 C) 1 D) 1.5 E) 2 F) 2.5 G) 3
32.) During the Kok cycle of PS II, the cubane cluster of one Ca and four Mn ions ha
ors its largest total charge at what stage?
A) S0 B) S1 C) S2 D) S3 E) S4 F) S5 G) All of the stages contain the same total charge.
33.) The substrates for the pentose phosphate shunt enzymes transketolase or transaldolase may contain a total of _____ ca
on atoms for each individual reaction.
A) 3 B) 5 C) 7 D) 9 E) 10 F) 12 G) D or E
34.) The major metabolite regulating the activity of glycogen phosphorylase is _____ in liver cells, and _____ in muscle cells.
A) glucose / ATP B) AMP / ATP C) ATP / glucose D) UTP / AMP
E) insulin / Ca2+ F) UTP / CTP G) glucagon / insulin
35.) If glucose-6-phosphatase was e
oneously abundantly expressed in muscle cells, which of the following effects would occur?
A) elevated blood concentration of glycogen B) elevated blood concentration of cholesterol
C) elevated blood concentration of epinephrine D) lowered blood concentration of bica
onate
E) decreased concentration of ATP in the muscle cytoplasm F) all of the above G) none of the above
36.) Effectively, how many protons of the gradient across the chloroplastic inner mem
ane are depleted when ATP synthase completes one full turn (360°) forming molecule(s) of ATP and relocating it(them) to the cytoplasm?
A) 0 B) 3 C) 4 D) 6 E) 9 F) 12 G) 14
Biochemistry CHEM 3500 Summer 2020 Exam 4 Name: ______________________________
Dr. Meades XXXXXXXXXXpossible points For questions 1-36, choose the one best answer (1 point each). You may keep the exam questions.
TURN IN THIS PAGE ONLY
Print, fill out by hand, take photo or scan ensuring choices can be read clearly, and email image/pdf of this answer sheet to: XXXXXXXXXX before 6:15pm. Late or non-hand written submissions will not be accepted.