Download BB 451/551 Exam 1 - Oregon State University

BB 451/551 Exam 1
Name______________________________
Please note that this is a practice exam. The exam you take will have the same
instructions, so you may want to familiarize yourself with these instructions before
going to your exam. Please note that the topics for exams vary from one exam to
another, so you may well see questions here that don’t relate to what has been talked
about this year in class.
General Instructions: This exam is worth 100 points total. Read the instructions for
each question carefully. If you do not understand the instructions for any section of the
exam, raise your hand. Do not spend too much time on any one question. Do not use
abbreviations for names of compounds or enzymes that we have not used in class. You
may, however, use any abbreviations that have been used by me in class. No one will be
permitted to work on the exam longer than 50 minutes. Budget your time
appropriately.
Section 1 __________
Section 2 __________
Section 3 __________
Total
__________
Do not open the exam until you are instructed to begin
BB 451/551 Exam #1, Page 1 of 6
Section I: (20 points total) The statements in this section can be completed by any of
the lettered responses following it. Each statement may have more than one answer
that is correct, one answer that is correct, or no answers that are correct. Students
should clearly circle only those responses that complete the sentence to make a
correct statement. Points will be awarded for each circled response that makes a
correct statement and for each uncircled response that makes an incorrect statement.
For example, the practice question below has three correct answers (b,c,d). You
would receive four points if you circled ‘b’,’c’, and ‘d’. You would receive one point
if you circled ‘a’ and ‘b’. You would receive no points if you circled only ‘a’. If we
have uncertainty about whether or not an answer is marked, it will automatically be
counted as a wrongly answered question. Be clear in your markings.
Practice question #A: Oregon State University
A. is a Bolivian factory
B. is located in Corvallis, Oregon
C. has a mascot named Benny Beaver
D. has students from all over the world.
Answers that should be circled are in BLUE BOLD
1. With respect to the reaction catalyzed by the pyruvate dehydrogenase complex,
A. Decarboxylation occurs prior to oxidation
B. NADH is produced by transfer of electrons form FADH2 to NAD+
C. Sulfurs assist by carrying electrons
D. A thioester bond is formed
2. With respect to metabolic control,
A. Tight coupling will destroy it
B. Shortage of ATP will stop complex V (ATP synthase)
C. The citric acid cycle will stop if the electron transport system stops
D. The proton gradient will increase as oxygen decreases
3. With respect to the lipid bilayer of cells,
A. Unsaturated fatty acids increase the Tm
B. Cholesterol broadens the range over which Tm is measured
C. Transverse diffusion rarely occurs spontaneously
D. Lateral diffusion requires enzymes called flipases
4. With respect to transmission of nerve signals,
A. ATP is the ultimate energy source for the Na+/K+ gradient formation
B. Movement of a neurotransmitter across the synaptic cleft stimulates release
+
of K ions
C. ATPase pumps move sodium in and potassium out
D. Ions only travel one way across the membrane
BB 451/551 Exam #1, Page 2 of 6
5. In the Q cycle,
A. Electrons are moving from coenzyme Q through Complex III to cytochrome
C
B. Incoming coenzyme Q donates one electron to cytochrome C and one to
another coenzyme Q
C. Protons are pumped into the mitochondrial matrix
D. Oxygen is the electron acceptor
Section II: (50 points total) Each sentence below in this section is missing a word or
phrase to complete it. Fill in the blank as appropriate to complete the sentence with a
correct statement. Each correctly filled in blank below will be awarded two points.
1. Under anaerobic conditions, the first effect in mitochondria will be stoppage of what
process? Electron transport
2. What type of bond in fatty acids favors fluidity of membranes at low temperatures?
Unsaturated
3. In the ATP synthase, what is the function of the T state? Make ATP from ADP +Pi
4. What is the name of the bond the oxygen molecule forms between the iron and
copper atoms of Complex IV? Peroxide bridge What is the charge on each of those
atoms at that time? Fe+++ and Cu++
5. What is the energy source of passive transport? Diffusion
6. What does a symport do? Move two molecules in same direction across a
membrane
7. The structure and name of the molecule produced in the citric acid cycle as a result of
oxidation of succinate is
BB 451/551 Exam #1, Page 3 of 6
Fumarate (you can look up structure) (four points)
8. The name of the enzyme of the citric acid cycle that utilizes lipoic acid Alpha-ketoglutarate dehydrogenase
9. Name the only molecule common to both the citric acid cycle and cholesterol
biosynthesis Acetyl-CoA
10. Name the only lipoprotein complex to travel in the lymph system Chylomicron
11. Name the cycle in bacteria and plants that enables them to synthesize glucose in net
amounts from acetyl-CoA Glyoxylate
12. What enzyme does lovastatin inhibit? HMG-CoA Reductase
13. Draw the structure of the molecule in the citric acid cycle that is produced by
oxidation of isocitrate Alpha-keto-glutarate (you can look up structure)
14. What is cellular complex is deficient in people with familial hypercholesterolemia?
LDL receptor
15. What effect does activation of uncoupling protein (UCP) have on cells in which it is
active? Increases temperature (decreases proton gradient)
16. What will happen to oxygen consumption in cells with UCP active? Increase
17. What class of molecules do aromatases catalyze the formation of? Estrogens
BB 451/551 Exam #1, Page 4 of 6
18. Name one five carbon building block of isoprenoids isopentenyl pyrophosphate or
dimethyallylpyrophosphate
19. Name an allosteric inhibitor of cholesterol synthesis cholesterol
20. In what process described in class is endocytosis important? LDL uptake by cells
21. Ultraviolet light is important for formation of a molecule in which biosynthetic
pathway described in class Vitamin D synthesis
22. What family of proteins described in class uses oxygen to perform hydroxylations?
Monooxygenases (P450)
23. What is the name of the linear 30 intermediate in cholesterol biosynthesis? squalene
Section III: (30 points total) 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/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 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 once, or not at all. If we cannot read your writing or if you put
two letters in any blank on the left, your answer will be counted wrong
automatically. Each correctly matched pair is worth two points.
__F__ 1. Sphingolipid
__L__ 2. Acetyl choline
__M_ 3. Copper
__G_ 4. Thiamine pyrophosphate (TPP)
__C_ 5. Complex I
__A_ 6. Glycerophospholipid
__Q_ 7. Farnesyl pyrophosphate
__D_ 8. Cytochrome c
__H_ 9. Aspartate
__B_ 10. Protons
__T_ 11. Cyanide
__E_ 12. Cristae
A. Phosphatidyl serine
B. Ion passing through complex V
C. Proton pumper
D. Peripheral membrane protein
E. Mitochondrial membrane infolding
F. Cerebroside
G. Activated acetaldehyde carrier
H. Mammalian NADH shuttle component
I. Citrate synthase substrate
J. Contains four carbons
K. Contains iron-sulfur proteins
L. Neurotransmitter
BB 451/551 Exam #1, Page 5 of 6
__R_ 13. Na+/K+ ATPase
__No answer__ 14. H2O
__I__ 15. Acetyl-CoA
M. Complex IV component
N. Complex V product
O. Passive transport channel
P. LDL component
Q. Cholesterol synthesis intermediate
R. P type ATPase
S. Complex V activator
T. Complex IV inhibitor
U. Malate decarboxylase substrate
Extra credit (2 points) – Why is eating puffer fish a potential hazard to your health?
It contains tetrodotoxin, a neurotoxin
BB 451/551 Exam #1, Page 6 of 6