1. The cell membrane (also known as the
plasma membrane) surrounding every cell
is composed primarily of ______.
A.DNA
B.Protein
C. Carbohydrates
25%
25%
25%
25%
s
ip
id
es
ra
t
Ph
os
ph
ol
bo
hy
d
Ca
r
Pr
ot
ei
n
DN
A
D.Phospholipids
A phospholipid molecule: composed of a
phosphate group and two fatty acid tails.
2. The phospholipids in the cell membrane
are arranged in a bilayer (double layer).
How are the phospholipid molecules
arranged in this bilayer?
A.The nonpolar (hydrophobic) ends of
the molecules faces inwards
B.The polar (hydrophilic) ends of the
molecules faces inwards
20% 20% 20% 20% 20%
an
d
C
B
an
d
th
Bo
th
Bo
of
ils
ta
c id
ty
a
ef
at
A
th
...
)e
...
lic
ph
i
hy
dr
o
r(
Th
ol
a
ep
Th
on
p
en
Th
E.Both B and C
ol
a
r(
hy
dr
op
ho
b
...
D.Both A and C
C
C.The fatty acid tails of the molecules
faces inward
 The hydrophilic phosphate groups facing outwards
helps the cell interact with the watery environment
on both sides of the membrane.
 The hydrophobic fatty acid tails in the interior of the
membrane help create a barrier for many molecules
to allow control of movement.
3. Channels through the phospholipid
membrane are formed by
25%
25%
25%
25%
A.Proteins
B.DNA
C.Cellulose
le
st
er
ol
Ch
o
se
lo
Ce
llu
DN
A
Pr
ot
ei
n
s
D.Cholesterol
4. The term permeability means
A.The ability of a substance to
bend
B.The ability of a substance to
allow gases or liquids to pass
through
25% 25% 25% 25%
ty
ab
ili
e
Th
c..
.
of
a
fa
yo
lit
bi
ea
Th
su
bs
ta
n
ce
...
sta
n
su
b
sta
n
su
b
fa
yo
lit
bi
ea
Th
Th
ea
bi
lit
yo
fa
su
b
sta
n
ce
...
D.The ability of a substance to
exist for a long time with out
deteriorating.
ce
...
C.The ability of a substance to
dissolve
Permeable surface
Impermeable surface
(not permeable)
5. In diffusion, molecules move
from _________________
concentration in a process that
__________________ additional
energy.
A.high to low; requires
B.high to low: does NOT
require
25% 25% 25% 25%
w
gh
to
lo
w
;r
eq
u
D.low to high; does NOT
require
ire
:d
s
oe
sN
OT
re
...
to
hi
gh
;r
eq
ui
gh
re
;d
s
oe
sN
OT
r..
.
C.low to high; requires
Additional energy is not required, because
diffusion occurs due to the random motion of
the molecules.
6. A hypotonic solution is one that
A. contains a higher
concentration of solutes
(dissolved particles)
B. contains an equal
concentration of solutes
20% 20% 20% 20% 20%
C. contains a lower
concentration of solutes.
n
er
c
co
nt
ai
ns
a
igh
ta
i
ah
co
n
co
nt
ai
ns
E. is at a lower temperature
on
ce
n.
eq
..
ua
lc
ns
on
al
ce
ow
...
er
is
at
co
a
nc
hi
en
gh
t..
er
.
is
te
at
m
pe
al
ra
ow
tu
er
re
te
m
pe
ra
tu
re
D. is at a higher temperature
Prefix reminders:
Hypo = below
Hypothermia is to have a body temperature
below normal.
Hyper= above
Hyperactive is to have high energy.
Iso= equal
An isoceles triangle has two equal sides.
7. If a cell with a 0.7 %sucrose
concentration inside is placed in a
solution that has a 0.5% sucrose
concentration, the process of osmosis
will occur. In this case,
A.sucrose will move into the cell
0.7 %
sucrose
B.sucrose will move out of the cell
O.5% sucrose
C.the cell will expand due to water
gain
17% 17% 17% 17% 17% 17%
eo
nt
o
ei
ov
ov
m
m
th
e
w
ill
ill
w
ro
se
ro
se
su
c
su
c
F.both B and D
ce
ll w
E.both A and C
th
...
ut
th
i
o
l
le
f.
e
ce
..
xp
ll w
an
d
ill
d
sh
ue
r in
..
kd
ue
t. .
.
bo
th
A
an
d
bo
C
th
B
an
d
D
D.the cell will shrink due to water
loss
Sucrose is too large to move through the
selectively membrane.
(Osmosis is occurring is a hint to this since it
means the movement of water.)
Remember that while the solutions are described
in terms of the solute concentration it is the
water that moves.
The solution that has a lower solute
concentration, has a higher water concentration.
Water will move from the hypotonic (low solute /
higher water) towards the hypertonic (higher
solute /lower water)
0.7 %sucrose
(99.7% water)
0.5% sucrose(99.5% water)
The shell-less egg in fresh water
(hypotonic) gained mass (water).
Water
Corn Syrup
Paramecium living in fresh water ponds has
to constantly pump out the water that
flows into the cell.
8. If a cell with a 0.9% salt
concentration inside is placed in a
1% salt solution, osmosis occurs.
Which of the following will happen
A.
the cell will shrink due to
water loss
B. salt will move out of the cell
C. the cell will expand due to
water gain
17% 17% 17% 17% 17% 17%
D. salt will move out of the cell
t..
.
du
e
ou
to
in
k
w
sh
r
ov
e
ec
el
l
m
ill
ill
w
ce
ll
w
t
F. both B and C
ft
ill
he
tw
ex
...
pa
ill
nd
m
ov
du
eo
e.
..
ut
of
th
e
...
bo
th
A
an
d
bo
D
th
B
an
d
C
E. both A and D
Salt is an ionic compound that can not move
through the nonpolar barrier of the
phospholipid membrane (without specialized
channels).
In osmosis, water will move in
the direction of the higher
SOLUTE (lower water)
concentration. Thus hypertonic
solutions, such as one high in
salt, causes cells to lose water.
• Drinking salt water will
dehydrate our cells
• Plants will wilt in a hypertonic
solution.
9. Which kind(s) of solution outside of
a cell could cause it to swell and
potentially lyse (burst open)?
A.
20% 20% 20% 20% 20%
a hypertonic
solution
B. a hypotonic
solution
a
d
C
an
B
bo
th
bo
th
A
an
d
ut
io
n
so
l
n
to
ni
c
ut
io
iso
an
hy
po
t
on
i
cs
ol
so
l
ni
c
yp
er
to
ah
E. both B and C
ut
io
n
D. both A and C
C
C. an isotonic
solution
10. A saline (salt) solution is used for
fluid infusions into the blood stream.
This solution needs to be ____ with
blood cells.
A. hypotonic
B. hypertonic
33%
33%
33%
to
ni
c
iso
c
on
i
hy
pe
rt
hy
po
t
on
i
c
C. isotonic
11. In an isotonic solution
A. the cell swells
25% 25% 25% 25%
B. the cell shrinks
..
w
of
m
ou
nt
la
eq
ua
an
at
o.
..
ks
th
er
e
is
NO
m
ov
em
en
t
sh
rin
th
e
ce
ll
sw
ce
ll
th
e
D. an equal amount of
water moves into the
cell as moves out
el
ls
C. there is NO
movement of water
in or out of the cell
12. When a cell is placed in an
isotonic solution,
A. there is no NET
movement of water
B. there is a dynamic
equilibrium
C. there is a static
equilibrium
D. both A and B
E. both A and C
is
th
er
e
th
er
e
is
no
NE
T
m
ov
em
a
dy
e.
th
na
.
er
m
ei
i
ce
sa
qu
st
il.
at
..
ic
eq
ui
lib
riu
m
bo
th
A
an
d
B
bo
th
A
an
d
C
20% 20% 20% 20% 20%
Net change = Inputs- Outputs. No net change
when inputs and outs are balanced.
Dynamic equilibrium= an equilibrium (balance) is
when there is motion but the inputs equal the
outputs.
13. When a substance is secreted from a
cell in a process in which a vesicle fuses
with the plasma membrane to release the
substance to the outside, it is called
25%
A. endocytosis
25%
25%
25%
B. exocytosis
C. osmosis
os
is
ha
lit
os
is
os
m
sis
yt
o
ex
oc
en
do
c
yt
os
is
D. halitosis
14. O2 is a small, nonpolar molecule. If it is
present outside the cell in high concentration
it can enter the cell by
A. Diffusion through the
membrane
20% 20% 20% 20% 20%
B. Passive transport
C. Active transport
Di
ffu
sio
n
C
d
A
an
d
an
A
ns
po
rt
tra
Ac
t iv
e
et
Pa
ss
iv
th
r
ou
gh
th
e
. ..
ra
ns
po
rt
E. A and C
B
D. A and B
15. Glucose is a larger polar molecule. If
it is present outside of the cell in high
concentration, it can enter the cell by
A. Facilitated diffusion
B. Passive transport
20% 20% 20% 20% 20%
C. Active transport
D. A and B
A
an
d
C
B
d
an
A
ns
po
rt
tra
Ac
t iv
e
ra
ns
po
et
Pa
ss
iv
Fa
c
ili
ta
t
ed
di
f fu
sio
n
rt
E. A and C
16. An amino acid (a large polar molecule) is
present outside the cell in low concentration. It
can be brought into the cell by
20% 20% 20% 20% 20%
A. Facilitated
diffusion through
specialized
channels
B. Passive transport
C
d
A
an
d
an
A
ns
po
rt
tra
et
Ac
t iv
e
ra
ns
po
.
th
r..
Pa
ss
iv
n
di
f fu
sio
ed
ta
t
ili
Fa
c
E. A and C
rt
D. A and B
B
C. Active transport
In facilitated diffusion, a channel allows the
substance to move through the membrane. But
no energy is provided, so it is a type of passive
transport and it can only move the substance
from high concentration to low concentration.
Active transport is required to move from low to
high concentration.
• High to low only
• Can move from low to
high
17. When a white blood cell engulfs a
bacterium, the process of _________
has occurred.
25%
25%
25%
25%
A.Endocytosis
B.Excocytosis
C.Osmosis
is
lys
Di
a
os
is
Os
m
cy
to
sis
Ex
co
En
do
cy
to
sis
D.Dialysis
18. What will happen for the following setup in which two different liquids are
separated by a selectively-permeable
membrane. The dots represent solute
particles that can not move through the
membrane.
A.Water will move to
the right
in
. ..
el
ys
te
m
es
Th
W
at
er
w
ill
w
m
ill
ov
e
re
m
to
ai
n
th
er
th
to
m
ov
e
ill
at
er
w
W
C.The system will
remain in
...
B.Water will move to
the left
33% 33%
ef
t
33%
(lower concentration of water)
1. D
2. D
3. A
4. B
5. B
6. C
7. C
8. A
9. B
10.C
11.D
12.D
13.B
14.D
15.D
16.C
17.A
18.A