Final Exam Key (BB 451/551) 2.

With respect to movement of compounds across biological

membranes,
A. active transport requires ATP
Section I: (40 points total) The statements in this section can be
B. water cannot readily cross membranes
completed by any of the lettered responses following it. Each
C. a proton gradient is required
statement may have more than one answer that is correct, one
D. protons generally require a protein to move across
answer that is correct, or no answers that are correct. Students
membranes
should clearly circle only those responses that complete the
sentence to make a correct statement. Points will be awarded
3. In tightly coupled mitochondria,
for each circled response that makes a correct statement and for
A. oxidative phosphorylation will speed up to make up for
each uncircled response that makes an incorrect statement. For
an oxygen deficit
example, the practice question below has three correct answers
B. low ADP levels will have the same overall effect as
(b,c,d). You would receive four points if you circled ‘b’,’c’, and
low oxygen levels
‘d’. You would receive one point if you circled ‘a’ and ‘b’. You
C. increasing intermembrane space pH will reduce ATP
would receive no points if you circled only ‘a’. If we have
production
uncertainty about whether or not an answer is marked, it will
D. cyanide will reduce both ATP production and the
automatically be counted as a wrongly answered question. Be
proton gradient
clear in your markings.
4. With respect to the Q cycle,
These are basically True/False questions. True answers are
A. it explains how electrons arrive in pairs, but are
marked below in RED
converted to moving singly
B. it involves coenzyme Q in three different forms
Practice question #A: Oregon State University
C. Cytochrome C carries electrons to complex III
A. is a Peruvian factory
D. each QH2 sends electrons to two different things
B. is located in Corvallis, Oregon
C. has a mascot named Benny Beaver
5. With respect to fatty acid oxidation,
D. has students from all over the world.
A. it occurs in the cytoplasm and the peroxisomes
B. it produces FADH2 and NADH
1. With respect to the citric acid cycle,
C. it only occurs on fatty acids shorter than 16 carbons
A. GDP is required
D. it occurs when the fatty acid is bound to ACP
B. lipoic acid has no role
C. oxygen is not a substrate in the reactions of the cycle
D. oxidative decarboxylation does not occur

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6. With respect to fatty acid synthesis, Section II: (80 points total) Each sentence below in this section
A. it is allosterically activated by palmitate/palmitoyl-CoA is missing a word or phrase to complete it. Fill in the blank as
B. it occurs in the cytoplasm and endoplasmic reticulum appropriate to complete the sentence with a correct statement.
C. it uses malonyl-ACP Each correctly filled in blank below will be awarded two points.
D. it requires a carboxylation and a decarboxylation
1. What coenzyme named in class does arsenate react with?
7. With respect to prostaglandins, lipoamide (lipoic acid)
A. aspirin is a COX inhibitor
B. inhibiting phospholipase A2 will stop release of
fatty acids from membranes 2. Which enzyme of the citric acid cycle catalyzes a reac-
C. they are precursors of cholesterol tion that produces FADH2?
D. they are pain relievers
succinate dehydrogenase
8. With respect to nucleotide metabolism,
A. it uses ribonucleotide reductase to convert all dNDPs to
3. What is the definition of an antiport?
dNTPs
B. it uses CTP to make UTP a membrane transport protein that moves two molecules in
C. it uses dTMP to make dUMP opposite directions across the membrase
D. it uses DHFR to make dNDPs from NDPs

9. With respect to transcription, 4. Which enzyme of the citric acid cycle catalyzes a reac-
A. it occurs at a structure called a replication fork tion that pulls the one preceding it?
B. the coding strand is complementary to the RNA being
made citrate synthase
C. it makes RNA in the 3’ to 5’ direction
D. it requires a ribosome 5. What amino acid is alpha-keto-glutarate readily con-

10. With respect to gene expression, verted to in an anaplerotic reaction?

A. attenuation involves early transcriptional termination glutamic acid
B. the lac repressor binds to DNA when it binds allo-lactose
C. CAP binds to DNA when it binds to cAMP
D. IRE-BP binds to DNA when it does not bind iron 6. Name one enzyme unique to the glyoxylate cycle
malate synthase or isocitrate lyase

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7. You take a heart cell that was treated with digitoxigenin 13. A cell (and its mitochondria) are treated with 2,4 dinitro-
and remove the digitoxigenin. What happens to the concen- phenol (2,4 DNP). What happens to the citric acid cycle
tration of calcium outside of the cell? in this cell?
increases speeds up

8. Name a specific sphingolipid named in class that con- 14. Name one of the two isoprenes described in class
tains a phosphate isopentenyl pyrophosphate or dimethylallyl pyrophosphate
sphingomyelin
15. Complex V has a rotating complex that makes ATP. It
9. Name the class of lipid described in class that contains has three different configurations. What is the form of
complex carbohydrates the configuration where ATP is released?
gangliosides the O configuration

10. A gradient of which ion is used as an energy source to 16. Describe precisely the catalytic activity of DNA Po-
remove calcium ions from heart cells? lymerase I that removes RNA primers.
sodium 5’ to 3’ exonuclease

11. What is the criterion we use to determine if a transport 17. Precisely what does telomerase copy to make a telo-
mechanism is active versus passive? mere?
active transport always has at least one molecule/ion moved a strand of RNA it carries
against a concentration gradient
18. How does one completely inhibit PRPP amidotransfe-
12. In what class of membrane transporters does phos- rase?
phoaspartate appear? with high amounts of both AMP and GMP
P-type ATPases

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19. What is the name of the molecules that donate single car- 25. Name a covalent modification of an enzyme in fatty acid
bons in nucleotide metabolism (hint – I’m not looking for metabolism and the effect of that covalent modification
carbon dioxide or bicarbonate) ? Enzyme modified = acetyl-CoA carboxylase
folates Modification = phosphorylation / dephosphorylation
Effect of modification = reduce activity / increase activity
20. What molecule does aspirin prevent from being acted
on by COX? 26. Name the enzyme used in DNA footprinting
arachidonic acid DNAse

21. In fatty acid synthesis, describe the chemical step after 27. Name the specific catalytic entity that forms phosphodi-
deyhdration (all I need is a name describing the chemical ester bonds between ribonucleotides.
reaction) RNA Polymerase
hydrogenation
28. Name the specific catalytic entity that forms peptide
22. Name the enzyme that catalyzes conversion of fatty ac- bonds between amino acids in bacteria
ids with a cis double bond between carbons 3/4 to a 23S rRNA
trans double bond between carbons 2/3?
enoyl-CoA isomerase 29. Define the term “template strand”
the strand of DNA that is “read” by RNA Polymerase during
23. What causes gout? transcription. It is complementary to the RNA that is made
overproduction of uric acid arising from purine catabolism
30. Name the protein described in class that unwinds DNA
24. Where does one find acyl-CoA dehydrogenases that act at 6000 rpm
on fatty acids of 20 carbons? helicase
peroxisomes

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31. In attenuation of the trp operon, what is the function of Section III: Matching. Each term on the left has a phrase or term on the
right which best describes or matches it. Place the letter of the term/
the structure in the mRNA that only forms when there is phrase on the right in the blank before the term on the left that it best
matches. Only one letter is appropriate in the blank. Note that there are
abundant tryptophan in the cell? more terms on the right than there are blanks, so not every term on the
right has a best match. Terms on the right may be used once, more than
termination of transcription once, or not at all. If we cannot read your writing or if you put two letters in
32. What does tamoxifen prevent the estrogen receptor any blank on the left, your answer will be counted wrong automatically.
Each correctly matched pair is worth two points.
from interacting with?
M 1. TPP A. Peptide bond catalyst(s)
co-activators N 2. Intron B. Purine breakdown product(s)
33. In elongation, which direction is the ribosome moving I 3. Transducin C. Binds retinal
P 4. Gyrase D. Hydrogenation byproduct(s)
relative to the mRNA? U 5. dATP E. tRNA component(s)
5’ to 3’ H 6. Inducer F. Spingolipid(s)
J 7. Thiolase G. Lagging strand synthesis product(s)
34. Name the 7TM of vision that is bound to Vitamin A
V 8. Statin H. IPTG
rhodopsin L 9. Active transporter I. G protein(s)
35. Name the G protein involved in the sense of smell X 10. Tamoxifen J. Ketone body enzyme(s)
D 11. Trans fat K. Prostaglandin enzyme(s)
Golf G 12. Okazaki fragments L. Na/K ATPase
36. Describe the unusual bond in a lariat structure T 13. Carnitine M. Pyruvate dehydrogenase complex
component(s)
5’ to 2’
E 14. Anti-codon N. pre-mRNA component(s)
37. Describe what rho does and how it does it A 15. Ribozyme O. Reverse transcriptase(s)
P. Topoisomerase(s)
termination of transcription - “climbs” the RNA and “lifts”
Q. Helicase(s)
the RNA Polymerase off of the DNA it is copying R. Translation chain terminator(s)
38. Precisely where is the wobble base of the anticodon S. Copper
T. Mitochondrial membrane crosser(s)
found ? U. Ribonucleotide reductase inhibitor(s)
5’ end of the anticodon V. HMG-CoA reductase inhibitor
W. Fatty acid synthase end product(s)
X. Estrogen receptor binder(s)

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