Đề kiểm tra môn sinh học quốc tế - Ngôn ngữ tiếng anh ( Đề 4 )

7 '
2.
1. There
are multiple versions
of the exam-
You
have version A.
Mark A for
question
1.
All
of the following compounds
are expected to make hydrogen
bonding interactions in
the cytosol, rather
than associating within
the
plasma
membrane, EXCEPT
A.
cholesterol
.Bl
Ohospholipid
head
groups
y'
glucose
't
,''
'.
D.

threonine
i
1
{xp
Which
of the following could be expected to DECREASE
the
fluidity
of a cell membrane?
A-
attaching oligosaccharides to the
polar
ends of
phospholipids
B.
increasing the
% of
phospholipids
with saturated fatty
acids
C. increasing
the temperature of the environment
D. decreasing
the
length
of
fatty
acid chains on
phospholipids
E.

decreasing the % of
phospholipids
with
saturated fatty acids
Which reaction
below,
if any, represents a catabolic
process?
A. 6CO2
+
6H2O
-
C6H12O6
+
69,
B.
Sucrose
-
fructose
+
glucose
C. amino
acids
*
protein
D. dNTPs
*
DNA
E. None ofthe
above

Which
of the following
sequences
represents
the complementary strand of
chromosomal DNA for the
seq
ue
nce
S'-AGCTGGCCTA-3'?
A.
5'-TCGACCGGAT-3'
B.
5'-UAGGCCAGCU-3'
C. 5'-ATCCGGTCGA-3'
D.
5'-TCGAGGCCAT-3'
E. 5'-TAGGCCAGCT-3'
6. The molecular formula
for
glucose
is C5H12O5.
What is the molecular
formula of
a
potymer
made
by
covalently linking
twelve

glucose
molecules
together by dehydration
reactions?
3.
4.
5.
I
t?"
(p
1'
A.
CnHuqOtz
R
C72H133051
lc)
crrH.,rro^,
D
CorHrggOor
E. CzzHr:aOao
it
Hr.0
"it-zt+
tl
CI
Lt,
Hrq.l OZz
t1-
o
b0

7. Which
of the following
statements is FALSE
about
enzyme-catalyzed reactions?
{
They
must still overcome
activation energy,
B. The
equilibrium
of the enzyme-catalyzed reaction
favors
products,
whereas
the
equilibrium for
the same reaction
in
the absence
of the enzyme favors reactants.
G: The
activation energy is
not the same as for
the un-catalyzed reaction.
-
B- The
activation
energy is lower than
that

for
the un-catalyzed
reaction.
E, The
free
energy change is
the same for the enzyme-catalyzed
reaction
as it is for
the
same reaction in
the

absence
of the enzyme.
8. According
to the fluid mosaic
model of membrane
structure,
integral membrane
proteins
are
primarily
X.
bound to the
surface of a lipid bilayer.
I
positioned
in
a continuous layer

across the entire inner
and outer
surfaces of the membrane.
(C)
oriented in
the
membrane
with a fixed inside-outside
polarity.
D:
contained
strictly within
the
hydrophobic interior
of
the membrane.
y'freelydiffusingintothesurroundingsolution.
Did
you
confirm
your
answer for
question
1,
the
version
of the
exam?
Page 1 of
8

a-
I
r
t-
,/
9.
Transmembrane
proteins
can have any of the following functions EXCEPT
/
A.
protein-protein
interactions.
B.
intercellular signaling.
C^ water channeling.
/D.)
enzyme synthesis.
)f active
transport.
10.
[hich
of the
following is NOT a characteristic of microtubules:
A
)
ffrey
associate
with myosin motor
proteins.

B. They
allow cilia to
beat in an oar-like
fashion.
C.
They
are responsible
for separating chromosomes during cell division.
D. They
are composed
of
globular
monomers
that
polymerize
asymmetrically.
E. They are
involved in vesicle transport.
11. lncubation of human cheek cells
in water causes the normally
flat
cells to assume a
round
shape.
The cause
of
this
phenomenon
is
A.

destruction of the
cytoskeleton
B.
destruction of the cell
wall
C. increased
phospholipid
synthesis
D. osmotic
pressure
E. damage to the
plasma
membrane
12. Actin filaments and microtubules
are similar in all of the following EXCEPT
X
they both form long
polymeric
structures
p1
tney are both components
of the cytoskeleton
CrAhey are both
multi-subunit filaments composed of
globular protein
subunits
O:
they are both used
for movement of
macromolecules

E. they both
polymerize
from centrioles
during celldivision in
animals
13. Most fat in mice is white fat, but a subset
of fat is known
as brown
fat. Brown fat
cells have a much higher
concentrationofmitochondriathanwhitefatce]ls.Thesemitochondria@portfrom
ATP
production-yet
still
metabolize
4ifitlllGaA.
What is most likely the function
of brown
fat versus white?
,2(
to
produce
high levels of COz that can be used
for
anabolic reactions
'9-
brown fat cells should
produce
more water
per

acetyl-coA than
white fat
cells
(prevents
dehydration)
C. to help
generate
heat
D. to regulate
pH
of the tissue
Wto
regulate the
endomembrane
system via feedback inhibition
14. Which
of the following statements is TRUE about a chemical reaction whose
equilibrium constant
(K"o)
is
greaterthan
10 al25"C?
A. The reaction
is not spontaneous.
B. Substrate
concentration
will
be
higher
than

product
concentration at
equilibrium
C. AG for
the
reaction is
positive
D. AG for
the reaction is negative
E. Whether
AG for the reaction is
positive
or negative
cannot be determined from
this
information
15. The transmembrane
regions of a transporter
protein
are
likely'to have
amino acids with
which type of R-
groups
exposed
to the
interior
of the
plasma
membrane?

A.
polar
B.
non-polar
C. acidic
D.
basic
E. charged
16. A
protein
component of
the
ribosome that interacts with
RNA would be expected
to have which of the
following
properties?
A. lt would have many
basic
sidechains on its external
surface.
B. lt would have many
acidic sidechains
on its
external surface.
C. lt would
be amphipathic.
D.
lt would be allosterically regulated.
E. lt would be regulated by reversible

phosphorylation.
Page 2
of 8
\
7',
17.
18.
Which
of the following intercellular
junctions
functions
to transfer molecules between
plant
cells?
A. desmosomes
B.
plasmodesmata
C. tight
junctions
D.
gap
junctions
E. intercalated discs
The
rate of an enzyme-catalyzed
reaction is found
to be 5 x 10-2 nmol/s. After the addition of 10
pmols
of
substance

Q,
the
reaction rate is measured at 3 nmol/s. The addition of more
substrate does
not
alter the
latter rate. Which of the following
is most logically
consistent with these data?
*i Substance
Q
is
a competitive
inhibitor of the enzyme.
p".
Substance
Q
is
a substrate.
/C.)
Substance
Q
is a
prosthetic group
for the enzyme in this reaction.
\
Subslance
Q
induces a conformational
change in the active site by binding elsewhere on the enzyme

,,E.
Ihe enzyme has
quaternary
structure.
19.
Which metabolic
process
is most closely associated
with
an
intracellular membrane?
A.
substrate-level
phosphorylation.
B. oxidative
phosphorylation.
C.
glycolysis.
D. the citric acid cycle.
E. lactate fermentation
20. A substrate lipid is known to bind
in
the
hydrophobic
pocket
of an enzyme.
Which
of the
following
amino

acid sidechains would
you
typically expect
to comprise such
a
binding
pocket?
A.
Sidechain
I
only
B. Sidechain llonly
C. Sidechain lll only
D. Sidechains I and ll
E. Sidechains ll and lll
a
i
#F*
,,'
,,
t
:
.
!i
#
'$,Fts
$
}r,.,
-'i
li:=

:$Y"E
I
qf'*r
r'
R
group
I
CH,
t-
cl'r"
t*
'fIHsc*flt
R
group
ll
R
group
lll
21. What
property
of the amino acid histidine makes it
useful in many
enzymatic reactions?
A. lt is hydrophobic.
Yll
has
a
p(
near neutral
pH.

C.
lt
can react covalently with substrates in
the transition state.
Pa
lt binds
to
ATP.
E. lt
stabilizes
protein
structure.
22. How
are enzyme-substrate complexes stabilized
during the
transitional
phase
(transition
state) of a chemical
reaction?
A. Weak
chemical forces
provide
sufficient binding
energy to reduce
G of the transition state
j<
,The
enzyme binds irreversibly to the transition
state structure

E Covalent bond(s)
provide
the binding energy necessary
to increase
G of the transition
state
-P1tne
enzyme
binds
rigidly
to the substrate in a
"lock-and-key"
type
interaction
E: The
enzyme accommodates
water molecules
that are hydrogen-bonded
to the
substrate surface
23. What
prevents
the spontaneous depolymerization of
polypeptides
into
amino acids?
A. Digestive
enzymes
are only
active at low

pH
B. Disulfide
bridges
C. The high
amino acid concentration
in healthy cells
D. The
activation energy of
peptide
bond hydrolysis
E. The negative free
energy
of
peptide
bond hydrolysis
Page 3 of 8
4
s
-ll
n' /'\'
''tru.
o=L-o,
Li.o
i i
o
I
}\J
{]!l
I
OH

0'i
Nl.rr
il
i ,I ,r'\m
o:iu
{u-Al
a ivo-l
\7
H
H
ogu
P
Hoo
a
25. Prokaryotes have a
proton
concentration
gradient
established across
their inner membrane. ln a bacterium
growing
anaerobically by
fermentation of
glucose
to ethanol,
what energy source is used to maintain that
from NADH
to oxygen
from Photosystem lto NADH
Which

A.
of the
following molecules
would
you
expect to be a competitive inhibitor of amylase?
B.
C.
E.
D.
{ E
""
r
tt*'#
p*,'g;
yu".*,H
*"
l{
u"l;{_
";";
o1roi1_r,,-,
cogcentration
gradient?
{,
Hign
energy
electrons tra nsferred
E.
Uign energy electrons transferred
/.

Arc
produced
by chemiosmosis
\./
"k
N/x
\C
\*1 \
)
*,"-*/
o,
Fo
,Fo
HN
/
'-lN\J'oH
il*11
./z\
-J
\ l'\
t"r u
\*/
)
-J
(-)
A
GTP
produced
by succinyl-CoA
synthetase

tF )
ATP
produced
by substrate
level
phosphorylation
26. What is
the
purpose
of establishing a concentration
gradient
across a biological membrane?
A. lt
provides
the energy for enzymatic reactions
B. lt
stabilizes the structure of
the lipid bilayer
C. lt
provides
a means of doing
work
D. lt reduces
the amount of
ATP in the cell
E. lt
stimulates
intercellular communication
27. The drug nocodazole destabilizes
microtubules. Actively

dividing human intestinalepithelialcells
grown
in
tissue culture can be treated with
nocodazole. Which
of the following effects would
you
expect to see fairly
immediately in actively dividing human
intestinal
cells in tissue treated with nocodazole?
A. inability
to divide
properly
B.
disrupted
vesicle
transport
C. inability to synthesize
DNA
D. AandC
E. AandB
_ $|,
N$+
"jta
li
-
^.4*
-J
*

't
r'x
gw
Y
ff 1-"*"_.
*rr
oo**L"x'*J,
q{-
{tti
I
'
'.,n-\
'J
n,
\-]d
rn!
r3*
Page 4
of 8
7
28. Animal cells often communicate
with their neighbors by transferring small
molecules from
one cell's cytosol
to the cytosol of another cell.
This exchange requires which of the following:
A.
tight
junctions
B.

gap
junctions
C. nuclear
pore
complexes
D.
plasmodesmata
E. desmosomes
29.
ln
the absence of oxygen,
the bacterium Geobacter
metallireducens can transfer an electron
from
cytoplasmic NADH to extracellular
ferric iron
(Fe3*)
through the electron transport
chain in its
ptasma
membrane. The free energy of this transfer
is used to
pump protons
into
the
periplasmic
space.
This is an
example of
what form of metabolism?

A. anaerobicfermentation
B. aerobic oxidation
C.
aerobicfermentation
D. anaerobic
ferridation
E. anaerobic
respiration
30.
One reason for the difficulty
in estimating
the total ATP
yield
of
eukaryotic
oxidative
phosphorylation
is:
A.
glycolysis produces
a
variable amount of
FADH2
P:
.lhe
electron
transport chain
can only oxidize Oz under
certain conditions
-

C. in some cell types, the transporter
that shuttles
electrons
from NADH
across
the mitochondrial membrane
transfers them to
FADH2
E
f nourhas morb free energy
that NADH
E
itdepends on which type
of
glucose
is
broken down
31.
For
the conversion
of acetyl-phosphate
to acetate and
inorganic
phosphate
(shown
below), a AG" of
-
8.5
kcal/mole has been
measured:

What would
ttre AGo
be for the reaction shown below,
where acetyl-phosphate is serving as the
phosphate
donor for the synthesis of
ATP?
Acetyl-phosphate
+
ADP
>
Acetate
+
ATP
A.
+
7.3 kcal/mole
@1
-
t.2 kcal/mole
Y 73kcallmole
D.
+
2.5 kcal/mole
E.
None of the above is correct
32. Choose the correct
path
of electrons during
photosynthesis:

kl Water )
Sugars ) Glycolysis
)
Calvin
cycle ) Electron
transport chain
fE)
Water ) Electron
transport chain
) NADPH )
Calvin cycle
)
Sugars
-G
_sugars
> NADPH ) Calvin cycle ) Electron transport chain ) Water
'p-NnOeH
) Electron transport chain
)
Calvin cycle ) Water ) NADP* ) Sugars
E Calvin cycle ) Electron transport chain
) Water ) NADPH
)
Sugars
33.
You
are collecting soil samples
from various
locations in order to determine which
types of bacteria are

present
using DNA
sequencing.
ln which of the following locations would
you
be most likely to find bacteria
known
to be obligate anaerobes?
{Topsotl
/
Sort
from
a fertile
garden
C, Soil from an isolated, undisturbed location
@
Sludge from
the bottom
of a lake
j<'Soil thatcontains a
lotof
organic
molecules
-
s.5
+
1.3
Page 5 of 8
ouf
34.

The
sodium-potassium
pump:
Po
A. Makes use of a
protein pump
that
could
be entirely composed of
polar
amino acids
lL
I
n
B. Pumps sodium ions from the outside to the
inside
of the cell
e1
,ls
an example of
facilitated diffusion
Operates
without
any
net energy
gain
or loss
Relies on conformational changes brought about by
phosphorylation
and later,

dephosphorylation, of the
protein
pump
35. You add labeled HzO in the form of
H218O to a mixture of isolated chloroplasts. After about
30
seconds
you
find
all of the
label
has been
incorporated and
you
isolate various molecules
as
listed.
Select the best
choice for
the expected^labeled
products.
A. only
'oO2
B. only H2180
c.
H2180
and
18o2
D. C6H121806and
H2180

E. only C6H121806
36.
Which statement below
is FALSE?
*)
(uilrio.t4,
HrO
f
0z
$.o
f
C)t
A. DNA
and
RNA
polymerize
in
one
direction as
incoming nucleotides are added to the 3' end
B. The DNA double helix
is formed by two complementary strands that
run antiparallelto each other
Q
Adenine and
guanine
have
purine
nitrogenous bases
while cytosine and thymine have

pyrimidine
bases
Q.
)
Phosphotriester
bonds
link the adjacent
nucleotides in DNA
and RNA
E. DNA and RNA synthesis and degradation
are catalyzed by specific
kinds
of
enzymes
37.
An increase in
the
amount of cholesterol
in an animal celt membrane is expected to
have what
effect
on the
cell's function?
A. increase
the number
of membrane
proteins
anchored to the extracellular
matrix
B. increase

the
hydrophilic character of the
membrane, leading
to enhanced
ion
transport
C. decrease
membrane fluidity at low temperature and
increase membrane fluidity
at
high
temperatures
@
increase membrane fluidity at low temperature and decrease
membrahe fluidity
at
high
temperatures
E. decrease the
amount of active transport
the cell can carry out
38.
Rurines
and
pyrimidines
are and
,
respectively
t/
two ring, one ring; nitrogenous bases

B.
polar,
non-polar, amino acids
C. one ring,
two
ring, nitrogenous bases
D. non-polar,
polar,
amino acids
E. ribose
and deoxy
ribose
sugars
39.
When
fatty acids are metabolized to
produce
ATP, they enter the
process
of cellular respiration at the level of
A.
succinyl-CoA
B.
citrate
C.
glucose
@
acetyl-CoA
H
pyruvate

40. Substrate-level
phosphorylation
in the Krebs cycle
depends directly on the energy
of the
Q)
thioester
bond of succinyl-CoA
B. oxidative
decarboxylation of
isocitrate
to o-ketoglutarate
C. thioester
bond of acetyl-CoA
D. NAD*-dependent
oxidation of malate to oxaloacetate
E. FAD-dependent
oxidation of succinate to fumarate
Page
6 of 8
r
(B)
'f'r-*
2. I
al
10.5+
GI
I
()
Time

2t
E-
o.sl
t
u1
I
-t
-I+
I
t
'tim.:
41.
For
the
enzyme-catalyzed
reaction
S

1)
p,
lGc
=
2. Which of the
following best represents
the
change
in
[S]
that
occurs over

time
when S is aidded to a
solution
containing the appropriate
enzyme?
I
z
to.:
,;.
{)
@
fi
ll
t\
Time
(A)
2"
ia:
?o
t?
/
/z
-
al
(l
rl
iE)
42. Which of the
following statements
about chloroplasts

and mitochondria
is FALSE?
.K
goicr.
organelles are
descended
from bacteria.
B. Both organelles can
synthesize
ATP using chemiosmosis.
f=Aotn
org anel
les contai
n ribosomes.
\
Aotn organelles contain a
membrane-bound
electron transport system.
(E.
)
Both organelles use
organic
molecules as a source of
high-energy electrons to
pump protons.
43. As the oxygen concentration
increases ina
C3
plant,
A. the rate of

photorespiration
increases.
-
B tne
rate
of
NAD+
oxidation
increases.
.{
tne
amount of
glyceraldehyde-'3-phosphate
that
is synthesized
increases.
D.
Only
A
and
B are correct.
E.
A,
B and C are
correct.
44. Which of the following
statements
regarding C-4
plants
is TRUE?

A. They contain both
mesophylland bundle-sheath
cells.
B.
They
grow
in
cooler
climates
with low amounts of sunlight.
C.
They
use
pyruvate
kinase for their
initial fixation of COz
D. They are uncommon
in nature.
E. They have no Rubisco.
Exam continues
Page
7
of 8
45. Which
of
the following
statements
about chlorophyll
is
FALSE?

A.
lt is
a
photosynthetic
pigment.
B.
lt is
green
in
color.
C. Only
one form
is found in
CAM
plants.
D. lt
absorbs
light in
the blue
and
red
regions
of the
spectrum.
E.
lt has
sufficient hydrophobicity
to associate
with
the thylakoid

membranes.
46. Which
of
the following is/are
TRUE
about the
movement
of cilia
and flagella
in Eukaryotes?
y-
Dynein"walks"
across a microfi
lament.
8
Because
of the wavelike
motion of
successive molecular
movements,
no energy input
is necessary.
C.
Cross-linking
proteins
cause cilia and flagella
to
bend instead
of sliding
past

each
other.
D.
None
of the above
statements are
true.
)dnn
of the above
statements are true.
47. During
the Calvin
cycle,
A.
ATP is
synthesized by substrate-level
phosphorylation
SlO,
is reduced
to
glyceraldehyde-3-phosphate
by Rubisco
C. lysosomes
degrade oxidized
chlorophyll molecules
D- ribulose-bisphosphate
reacts with
Oz
(e)
runoPH

is oxidized
to NADP*
\_-/
48. Which
of the following
is NOT
a difference between
photosynthesis
and cellular respiration?
A
Photosynthesis
produces
02, respiration
produces
CO2
p.
Photosynthesis
consumes
CO2; respiration
consumes
02
Q.)nf
e is
produced
during
photosynthesis
but not
during respiration
pZehotosynthesis
is

powered'by
light
energy; respiration
is
powered
by
the chemical
energy of reduced
organic
molecules
JAne
principle
electron carrier in
respiration is
NAD*;
the
principle
electron
carrier in
photosynthesis
is NADp*
49. ln
yeast
cells living in
an oxygen-free
environment,
A.
glucose
is
produced

from
CO2
B.
ethanol
is
produced
during
the citric
acid cycle
(C)
ethanol is
produced
after
glycolysis
D. lactate
is
produced
during
glycolysis
E. lactate
is
produced
during
anaerobic
respiration
50. ln C4
plants,
carbon fixation
takes
place

in
the
using
and
then is
transferred
to the
where
it
enters the Calvin
cycle.
qA)
Mesophyll
cells, PEP
carboxylase,
bundle-sheath
cell
B.
Stomata, PEP
carboxylase,
mesophyllcell
C. Bundle-sheath
cell, Rubisco,
mesophyll
cell
D.
Mesophyll
cells, Rubisco,
bundle-sheath
cell

E.
Stomata,
Rubisco,
bundle-sheath
cell
51. Evolution
of
biological
order is
consistent
with
the second
law
of thermodynamics
in
that
filving
systems
are closed
systems
and
cannot
exchange
energy
and matter
with
their
surroundings.
($)
living

systems
maintain
order
by increasing
the
entropy
of their
surroundings.
C. living
systems
escape
the
consequences
of
the second
law
of thermodynamics
by
transforming
energy.
D. A,
B,
and C are
allcorrect
statements.
E.
B and
C are
correct.
END

OF THE
EXAM
Page
8 of
8
to35lA
to36lD
lo37lD
to38lA
lo3el
D
lo4olA
lQ41lC->B
lo42lE
lo43lA
lo44lA
lo45lc
lQ46lD->C
lo47lE
lo48lc
lo4elc
tosolA
tollA
lQ2l
D*>A
to3lB
to4l
B
tosl
E

to6lc
IOTI
B
toBIC
loel
D
lo10lA
to11lD
lo12l
E
lo13lc
lo14lD
lo15l
B
lo16lA
lQlBlC:>D
tolel
B
lo20l
D
lQ21lE->B
to22l
A
lo23l
D
lo24lc
lo2slE
1026lc
lo27l
E

lo28l
B
lo2elE
lo3olc
to31lB
lo32l
B
to33l
D
As rnentioned on the
syllabus we
guarantee
a score of
90 %
or above
is
some
fioJ,ff
of an
A, a score of 80-89%
is some form of a8,70-79%
is some
form of a C,60-69%
is
some
form of a D. The
grades
reflect this.
There
are

more Bs
than we
typically
give
(in
a curved situation).
There are two versions of the exam with
the same
questions
and the
same answer
selections butthe
two versions of the
exam
have the
questions
and
the
answers in different orders.
Thus
you
will
need to
go
log on to bSpace
for
a
key for
your
version

of
the exam,
Version A or Version B.
Please be sure to
put
your
name on
your
exam and to
fully
bubble
in
your
SID and
section numbep for exam
2.