1, Principal classes of
membrane proteins include all of the following except
A) receptors
B) cell surface markers
C) spectrins
D) transport proteins
2. Which of the following
are not components of the cell membrane?
A) cell surface markers
B) transmembrane proteins
C) interior protein
network
D) plasmodesmata
3. To cross the cell
membrane, water must
A) squeeze between
phospholipid molecules
B) pass through
aquaporins
C) be transported at the
expense of ATP
D) be moved by a
cotransport system
4. If a cell's contents are
greatly hypoosmotic to the surrounding environment, the cell will probably
A) expand
B) become isotonic
C) burst
D) shrivel
5. The sodium-potassium
pump passes
A) more Na+ out than K+
in
B) K+ out and Na+ in on a
one-for-one basis
C) Na+ out and K+ in on a
one-for-one basis
D) K+ and Na+ in the same
direction
6. Exocytosis is a process
by which cells
A) pass substances out of
the cell in vesicles
B) pass substances out of
the cell through the membrane by osmosis
C) release substances
directly into the extracellular fluid through a pore
D) release substances
directly into the extracellular fluid through a pit
E) identify substances
in the environment
7. A phospholipid has
A) a phosphate group in
place of one fatty acid
B) phosphate groups in
place of two fatty acids
C) phosphate groups in
place of three fatty acids
D) a phosphate group in
place of a carbon in glycerol
E) none of the above
8. Clathrin-coated pits are
used to
A) extrude bulk fluids
from the cell
B) allow desired
molecules directly into the cytoplasm
C) pass wastes in
vesicles to the outside.
D) pass information into
adjacent cells
E) bring desired
substances from the environment into the cell in vesicles
9. A lipid bilayer
A) permits water soluble
molecules to pass through it
B) facilitates the
passage of water soluble molecules through it
C) inhibits the passage
of water soluble substances through it
D) actively transports
water soluble molecules through it
E) is indifferent to the
passage of water molecules through it
10. A cell is recognized by
other tissue members as "self" by its surface
A) glycolipids
B) phosphate groups
C) glycoproteins
D) ketoglutaric acids
E) glycocarbohydrates
11. A net gain of water
tends to occur
A) in a hypoosmotic
solution from an isosmotic solution
B) in an isosmotic
solution from a hyperosmotic solution
C) in a hyperosmotic
solution from a hypoosmotic solution
D) in a hypoosmotic
solution from a hyperosmotic solution
E) in one isosmotic
solution from another isosmotic solution of the same composition
12. Red blood cells have a
characteristic concave shape because of
A) spectrin
B) dextrin
C) hemoglobin
D) hemocyanin
E) iron
13. By a mechanism called
cotransport
A.
sugar moves down its concentration gradient
while sodium moves up its concentration gradient
B.
sodium moves outward against is concentration
gradient while sugar moves inward down its concentration gradient
C.
sugar and sodium move inward down their concentration
gradient
D.
sodium moves inward down its concentration
gradient while sugar moves inward up its concentration gradient
E.
sodium and sugar move outward against their
concentration gradient
14. Many surface proteins
are anchored by
A) polar amino acids
B) hydrogen bonding amino
acids
C) nonpolar fatty acids
D) nonpolar amino acids
E) polar fatty acids
15. Transmembrane proteins
are
A) always fixed in
position
B) always abundant
C) often not fixed in
position
D) never abundant
E) none of the above
16. Cystic fibrosis results
from defective ion channels for
A) Na+
B) Cl-
C) Ca++
D) ClO3-
E) H+
17. Fluidity of
phospholipid bilayer is increased by
A) double bonds between
carbon atoms in the fatty acid tails
B) steroid lipids at
certain temperatures
C) poor alignment of the
fatty acids tails
D) cholesterol at certain
temperatures
E) all of the above
18. A cell engaged in
phagocytosis must be
A) engulfing a live
organism
B) acquiring a liquid
C) engulfing a dead organism
D) transporting bulk
dissolved nutrients
E) transporting bulk
solid material
19. A, B, and O blood
groups are marked by surface
A) glycoproteins
B) glycolipids
C) glycocarbohydrates
D) glycerol
E) gluterates
20. In each cycle the sodium-potassium
pumps transfer
A) two potassium ions in
and two sodium ions out
B) one sodium ion out and
one potassium ion in
C) three sodium ions out
and two potassium ions in
D) one potassium ion out
and two sodium ions in
E) three sodium ions in
and two potassium ions out
21. ____________________
are transported by a particular carrier or pass through a particular channel.
A) All water soluble ions
or molecules
B) Certain water soluble
molecules or ions
C) All insoluble
molecules or ions
D) Certain insoluble ions
or molecules
E) Only the smallest
molecules or ions
22. Equilibrium is reached
in an aqueous solution when
A) random motion stops
B) water molecules and
dissolved molecules are moving at the same rate
C) the dissolved
molecules or ions are equally distributed throughout the solution
D) molecular motion stops
E) there are the same
number of water molecules as dissolved molecules
23. Substances transported
by facilitated diffusion
A) move passively through
specific channels from an area of greater concentration to one of lower
concentration
B) are limited to
solvents
C) must have movements
coupled to those of other substances
D) may flow to a region
of higher concentration by the expenditure of energy
E) are restricted to only
one direction through the membrane
24. In a lipid bilayer the
lipids have
A) their water repelling
heads facing inward
B) their water repelling
tails facing inward
C) their hydrogen bond
forming heads facing inward
D) their hydrogen bond
forming tails facing inward
E) no relationship to
water
25. A lipid bilayer is held
together by
A) surface tension
B) double bonds in their
fatty acid tails
C) the attraction of the
phospholipid heads to each other
D) hydrogen bonding with
water
E) the electrostatic
attraction of phosphate groups for each other
26. The glycocalyx is a
"sugar coating" on the surface of a cell resulting from the presence
of polysaccharides on glycolipids and glycoproteins embedded in the outer layer
of the plasma membrane.
A) True
B) False
27. Threonine, an amino
acid, and arabinose, a monosaccharide, cross the cell membrane down their
concentration gradients by:
A) diffusion.
B) endocytosis.
C) phosphorylation.
D) facilitated diffusion.
E) osmosis.
28. A contractile vacuole
is an organelle that pumps excess water out of many freshwater protozoan cells.
A freshwater protozoan was placed in solution A and observed to form
contractile vacuoles at a rate of 11 per minute. The same protozoan was then
placed in solution B and observed to form contractile vacuoles at a rate of 4
per minute. Based on this information, which of the following statements is
correct?
A) Solution A is
hyperosmotic to solution B.
B) Solutions A and B are
isosmotic.
C) Solution B is hyperosmotic
to solution A.
D) Solutions A and B are
isosmotic to the protozoan cell.
E) Both a and b.
29. The net movement of
uncharged, polar molecules across a semipermeable membrane from a low
concentration to a high concentration occurs by facilitated diffusion.
A) True
B) False
30. The membrane transport
mechanism used when an amoeba engulfs a bacterial cell is called:
A) exocytosis
B) pinocytosis
C) facilitated diffusion
D) active transport
E) phagocytosis
31. Continuing from the
previous question, once the bacterial cell has been digested, the amoeba will
dispose of indigestible materials by which of the following processes?
A) facilitated diffusion
B) through gated channels
in membrane proteins
C) exocytosis
D) active transport
E) by any of the above
processes
32. ATP is required in the
transport of
A) water molecules
B) all molecules across a
membrane
C) molecules to areas of
lower concentrations
D) molecules to areas of
higher concentrations
E) molecules through a
protein channel
33. The sodium-potassium
pump establishes concentration gradients
A.
of higher sodium concentrations inside the cell
and higher potassium concentrations outside the cell
B.
of sodium and potassium but the area of their
concentrations (inside or outside) depends on the needs of the cell
C.
of higher potassium concentrations inside the
cell and higher sodium concentrations outside the cell
D.
of ATP inside the cell where it is needed
E.
by pumping sodium outside the cell and potassium
is cotransported out as well
34. In cotransport
processes, sugars can be brought into the cell against their concentrations
gradients
A) because ATP powers the
pump that brings them in
B) because they follow
sodium ions into the cell which are traveling down their concentration
gradients
C) because they follow
potassium in through the sodium-potassium pump
D) through endocytosis
E) sugar enters the cell
by all of the processes listed above
35. The methods of membrane
transport that don't require protein channels or carriers are
A) osmosis
B) diffusion
C) phagocytosis
D) exocytosis
E) all of the above
ANSWER
- 1. C 2. D 3. B 4. D 5. A 6.A 7. A 8. E 9. C 10. C
- 11. D 12. A 13. D 14. D 15. E 16. B 17. E 18. E 19. B 20. C
- 21. B 22. C 23. A 24. B 25. D 26. A 27. D 28. C 29. B 30. E
- 31. C 32. D 33. C 34. B 35. E
