Quiz 5
Ch 5
Name________________________
Remote # ____________
4. In osmosis, water diffuses from the
side of the membrane with a higher
concentration of water to the side with a
lower concentration of water. What
determines the concentration of water in
a solution?
a. the volume of the solution
b. the amount of molecules other than
water dissolved in the solution
c. the size of the container
.
5. Which of the following processes
does a cell use to take up molecules
against their concentration gradient?
a. simple diffusion
b. facilitated diffusion
c. active transport
d. endocytosis
e. Both the c and d are correct.
1. The fluid mosaic model describes
membranes as fluid because
___________.
a. the phospholipids of membranes are
constantly moving from one layer to the
other layer
b. the membrane is composed mainly of
water
c. the phospholipid molecules are
bonded to one another, making them
more moveable
d. the phospholipids move from place to
place around the motionless membrane
proteins
e. the phospholipids and proteins move
from place to place within the bilayer
2. Which of the following types of
molecules must pass through
membranes via the aqueous pores
formed by membrane proteins?
a. gases such as carbon dioxide and
oxygen
b. small polar molecules such as water
and ethanol
c. large particles such as bacteria
d. small charged ions such as Na+ and
Ca++
6. When placed in a certain sucrose
solution, the volume of a cell decreases;
therefore, the sucrose solution is
__________ to the cell contents.
a. isotonic
b. hypertonic
c. hypotonic
d. cannot determine from given
information
3. Diffusion is the movement of
molecules from __________.
a. an area of higher concentration of
that type of molecule to an area of lower
concentration
b. an area of lower concentration of that
type of molecule to an area of higher
concentration
c. outside the cell to inside the cell
7. Choose the substance that will diffuse
most rapidly across the plasma
membrane.
a. amino acid
b. sodium ion
c. small polar molecule such as water
d. oxygen
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8. Facilitated diffusion requires
__________.
a. a membrane transport protein
b. a concentration gradient
c. energy
d. a membrane transport protein and a
concentration gradient
9. Many metabolic poisons work by
inhibiting ATP production. Which type of
transport would be most affected?
a. osmosis
b. facilitated diffusion
c. active transport
d. simple diffusion
10. Two types of connections between
cells called "gap junctions" and
"plasmodesmata" are specialized to
__________.
a. prevent the movement of molecules
between cells that are tightly joined
along ribbons of cell membrane
b. tightly hold one cell against another at
focal points, almost like a spot weld of
superglue
c. permit the passage of substances
(e.g., ions) between cells through small
passageways that directly link the
cytoplasm of one cell to the cytoplasm
of another cell
d. None of these are correct.
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