Test 3, Monday, March 9, 2015. BCH 400.
Name___________________
Put Name on: First and Last Page, AND
Scantron. When done, turn in TEST and
Scantron
For questions 1 to 4, refer to the figure of
glycolysis to the right. For each numbered
arrow, indicate the most appropriate input or
output from the following choices. (Note, a letter
may be used more than once)
a. NADH goes in
b. NADH comes out
c. ATP goes in
d. ATP comes out
e. FADH2 comes out
5) Which of the following enzymes controls the
first committed step in glycolysis?
a. Glut4
b. Hexokinase
c. Phosphoglucose isomerase
d. Phosphofructokinase
e. Aldolase
6) Under conditions that favor glycolysis,
phosphogylcerate kinase catalyzes the addition
of a phosphate to which of the following?
a. pyruvate
b. phosphoenolpyruvate
c. ADP
d. Akt kinase
7) Which of the following has the lowest
phosphoryl group transfer potential (i.e., “lowest
energy”)?
a. ATP
b. Phosphoenolpyruvate
c. 1,3-Bisphosphogylcerate
d. phosphocreatine
e. Glucose 6-phosphate
1
2
3
4
8) Which of the following activities is not
directly connected to one of the many ABC
(ATP binding cassette) transporters?
a. Calcium release from the ER
b. “Multidrug resistance”
c. Chloride channel conductance
d. Lipid floppase
e. ATP hydrolysis
9) In the structures shown to the right, which ester bond is associated
with an Acyl Co-enzyme A (Acyl-CoA)? (A, B, C or D)
10) When ATP is hydrolyzed into AMP and PP (i.e., products), which
of the following is MOST likely to be true?
a. The reaction has a positive ∆G
b. Products have more intramolecular electrostatic repulsion
c. Products have greater number of resonance structures
d. The cleavage reaction breaks a glycosidic bond
Figure 2
11) In Figure 3, which enzyme is most
likely associated with step 1?
a. Pyruvate decarboxylase
b. Alcohol dehydrogenase
c. Lactate dehydrobenase
d. Acetyl-CoA carboxylase
e. Phosphoenolpyruvate
carboxlyase
Fig. 3
12) Which of the following has the LEAST oxidized carbon?
a. methane
b. methanol
c. formaldehyde
d. formic acid
e. carbon dioxide
13) Which of the following concentration relationships is the MOST likely to be wrong?
a. 300 to 500 mM Na+ = concentration in the ocean
b. 140 mM Na+ = typical concentration of Na+ in the cytoplasm of a pancreatic cell
c. 10 to 100 nM Ca++ = resting concentration of Ca++ in the cytoplasm of a pancreatic cell
d. 4 mM ATP = typical concentration in a liver cell
e. 25 mM Creatine Phosphate = typical concentration in a resting muscle cell
14) In Figure 3, which of the following
molecules corresponds to “B”?
a. Pyruvate
b. Acetaldehyde
c. Acetone
d. Oxaloacetate
Figure 4
15) When the pufferfish tetrodotoxin blocks a Na+ channel, this initially prevents Na+ from _____________.
a. moving down a concentration gradient into the cell
b. moving down a concentration gradient out of the cell
c. moving up a concentration gradient out of the cell
d. being pumped by the Na+/K+-ATPase
e. being effluxed through a Na+/Ca++ exchanger
A
16) Protein Kinase C is most activated by a direct interaction with
which of the following?
a. cAMP and DAG (diacylglycerol)
b. cAMP
c. a stimulatory G-alpha in GTP bound form
d. calmodulin
e. Ca++ and DAG (diacylglycerol)
17) Which of the two nucleotide triphosphates shown to the right is
GTP? (A or B)
18) Protein Kinase A is most activated by which of the following?
a. calmodulin
b. Ca++ and DAG (diacylglycerol)
c. DAG (diacylglycerol)
d. cAMP
e. a G-alpha in GDP bound form
A
B
19) In the Epinephrine triggered signaling pathway discussed in class, cyclic AMP is formed from ATP by a cyclase reaction
that includes which of the following nucleophilic attacks?
a. P in the alpha phosphate 2 is the nucleophile that attacks the O in Carbon 2
b. P in the alpha phosphate 2 is the nucleophile that attacks the O in Carbon 3
c. 0 linked to Carbon 3 is the nucleophile that attacks the P in the alpha phosphate
d. 0 linked to Carbon 2 is the nucleophile that attacks the P in the alpha phosphate
20) Which of the following membrane lipids shows an asymmetric distribution between the inner and outer monolayers of the
erythrocyte plasma membrane?
a. Phosphatidylethanolamine
b. Phosphatidylcholine
c. Sphingomyelin
d. Phosphatidylserine
e. All of the above
21) Which of the following is least likely to result from insulin stimulation of the insulin receptor on a muscle cell?
a. Tyrosine phosphorylation of the receptor
b. Activation of the phosphatidylinositol-3,4,5-triphosphate dependent protein kinase
c. Activation of the Akt protein kinase
d. Activation of a phosphoinositide 3 kinase
e. Turning on gluconeogenesis
22) In liver, which of the following would most likely stimulate glycolysis?
a. Allosteric inhibition of phosphofructo-kinase activity by ATP
b. Increase from 0 to 1 micromolar of Fructose-2,6 bisphosphate (F-2,6-BP)
c. Increased levels of ATP
d. Increased activity of PKA (protein kinase A)
23) In active muscles, which of the following would most likely stimulate glycolysis?
a. Increasing AMP levels
b. Allosteric activation of phosphofructokinase-1
c. Inhibition of Hexokinase
d. a and b
e. all of the above
24) In fermentation of pyruvate to ethanol, pyruvate decarboxylase utilizes
thiamine pyrophosphate (TPP) in a nucleophilic attack on pyruvate. Which
atom functions as the electron poor electrophile (see structures to right)?
a) A
b) B
c) 1
d) 2 e) 3
25) When glucose levels in the blood are low ( ~ 5 mM), which of the
following glucose transporters is most likely to have a higher
rate of glucose transport?
a. Glut2 (KM = 15 mM)
b. Glut4 (KM = 5 mM)
c. Both Glut 2 and 4 will transport at the same rate at this
concentration
26) Which structure to the right most closely resembles
Vitamin E?
27) Which structure to the right most closely resembles
Riboflavin (Vitamin B2)?
28) Which of the following peptides would have more positive
charges at a pH typically found in the cytosol of a eukaryotic
cell.
a. Lys-Arg-Asp (KRD)
b. Lys-Glu-Asp (KED)
c. Lys-Gln-Asp (KQD)
d. Lys-Cys-Asp (KCD)
e. Lys-Asn-Asp (KND)
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29) Which of the following pairings between a molecule and its effect is most likely incorrect?
a. IP3 (inositol triphosphate) ………… stimulates release of Ca2+ from endoplasmic reticulum
b. caffeine /theobromine ………. stimulates cAMP phosphodiesterases
c. stimulatory G-alpha with GTP ………… activates Phospholipase C
d. choleocystokinin CCK
…………stimulates a G-protein coupled (7TM) receptor
e. Cholera Toxin ………inhibits the GTPase activity of a G-alpha
30) Which of the following is LEAST likely to be a feature associated with the EGF (epidermal growth factor receptor)
signaling pathway?
a. The receptor catalyzes the phosphorylation of tyrosine residues
b. Includes the exchange of GTP for GDP in a GTPase called Ras
c. Includes a Ras activated serine threonine protein kinases
d. Includes activation of a RUBISCO activase
31) Which of the following does not directly activate a G-protein coupled receptor?
a. Glucagon
b. Vasopressin
c. CCK (Cholecystokinin)
d. Morphine
e. Gleevec
32) Which the following best describes important features of HIF-1?
a. HIF-1 is activated under conditions of hypoxia
b. HIF-1 promotes blood vessel growth to tumors
c. HIF-1 promotes the expression of genes encoding glycolytic enzymes
d. A and B
e. All of the above
33) Which of the following membrane potentials would be most typical for an animal cell plasma membrane?
a) 6mV b) 6
0mV c) 120mV d) 160 mV e) 600 mV
34) Which of the following is least likely to be a feature associated with the activity of a K+ selective ion channel in a
mammalian cell plasma membrane?
a. A positive ∆G will be associated with removal of the hydration shell surrounding a K atom
b. A negative ∆G will be associated with binding of the K atom within the channel domain
c. Movement through the channel involves ionic repulsion between a K+ and K+ ions in the channel domain
d. The membrane potential (negative inside) drives K efflux (out of the cell)
35) Which of the following is most likely incorrect for pairings between a vitamin and a coenzyme/reaction type/deficiency
symptom?
a. Thiamine B1——— TPP/aldehyde transfer/Beriberi
b. Riboflavin B2 ——- FAD/oxidation reduction/dermatitis
c. Pantothenic acid —- Coenzyme A/acyl-group transfer/hypertension
d. Niacin —————– Lysin adducts/Carboxyl-group transfer/muscle pain
For 36 to 39, match each enzyme with the most appropriate phosphorylation modification involved in the enzyme mechanism
or activity of the protein (note, each letter can be used more than once)
.
36) Protein Kinase C
a) Phospho-Histidine
37) Vascular endothelial growth factor (VEGF) Receptor
b) Phospho-Tyrosine
38) Phospho-glycerate mutase
c) Phospho-Serine/Threonine
39) Calmodulin-activated Calcium Pumps (Ca-ATPases)
d) Phospho-Aspartate
40) In a fun fact provided by Riley Kellermeyer, it was noted that high concentrations of a Nerve Growth Factor (NGF) are
found in mouse saliva. When mice lick a wound, this NGF has been found to increase the rate of healing by 2-fold. The
receptor kinase that is triggered by NGF is similar to the Epidermal Growth Factor (EGF) Receptor, which was discussed in
class. Given your knowledge of the EGF receptor, which of the following is most likely phosphorylated by this kinase?
a. Histidines
b. Membrane lipids
c. Aspartates
d. Tyrosines
e. P-type ATPases
Please put your name on this page.
Name___________________ ________________________________
Please provide drawings on this page (on back is ok), as well as answer numbered questions on the scantron.
Remember, no drawing …….“no points”.
Draw the structure of pyruvate and answer
questions 41 to 43 on the scantron.
41) How many C-C bonds are in pyruvate?
a) 1 b) 2 c) 3 d) 4 e) 5
42) How many Os are in pyruvate?
a) 1 b) 2 c) 3 d) 4 e) 6
43) In the cytosol, pyruvate is expected to
ionize and have what charge?
a) +1 b) 0 c) -1 d) -2 e) -3
Draw the structure of glyceraldehyde 3phosphate and answer questions 44 and
45 on the scantron.
44) How many Os are in this molecule?
a) 3 b) 4 c) 5 d) 6 e) 7
45) How many Hs are covalently attached to
Carbons in this molecule?
a) 3 b) 4 c) 5 d) 6 e) 7
Draw the structure of the product resulting
from the incorporation of an Arsenate (As)
(instead of Phosphate) in a reaction
catalyzed by glyceraldehyde-3 phosphate
dehydrogenase and answer questions 46
and 47 on the scantron.
46) Which C position would the Arsenate
modification be attached to in this molecule?
a) 1 b) 2 c) 3 d) 4 e) 6
47) How many Os are in this molecule?
a) 6 b) 8 c) 10 d) 12 e) none of the above
Draw the structure of fructose 1,6 bisphosphate and answer questions 48 to 50
on the scantron.
48) How many Os are in this molecule?
a) 6 b) 8 c) 10 d) 12 e) 14
49) How many Hs are covalently attached to
Carbons in this molecule?
a) 3 b) 4 c) 5 d) 6 e) 7
50) In the kinase reaction that adds a P to make
fructose 1,6 bis-phosphate, which of the
following ions is most likely involved in the
reaction mechanism?
a) Zn2+ b) Mg2+ c) Ca2+ d)As2+ e) Cu2+
