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
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
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
Fumarate (you can look up structure) (four points)
8. The name of the enzyme of the citric acid cycle that utilizes lipoic acid Alpha-keto-glutarate 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
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. SphingolipidA. Phosphatidyl serine
__L__ 2. Acetyl cholineB. Ion passing through complex V
__M_ 3. CopperC. Proton pumper
__G_ 4. Thiamine pyrophosphate (TPP)D. Peripheral membrane protein
__C_ 5. Complex IE. Mitochondrial membrane infolding
__A_ 6. GlycerophospholipidF. Cerebroside
__Q_ 7. Farnesyl pyrophosphateG. Activated acetaldehyde carrier
__D_ 8. Cytochrome cH. Mammalian NADH shuttle component
__H_ 9. AspartateI. Citrate synthase substrate
__B_ 10. ProtonsJ. Contains four carbons
__T_ 11. CyanideK. Contains iron-sulfur proteins
__E_ 12. CristaeL. Neurotransmitter
__R_ 13. Na+/K+ ATPaseM. Complex IV component
__No answer__ 14. H2ON. Complex V product
__I__ 15. Acetyl-CoAO. 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 1 of 51