1.
The cell membrane:
allows some substances to pass into and out of the cell
prevents all substances from passing into and out of the cell
is composed of a protein bilayer
is composed of a lipid bilayer
2.
When a human red blood cell is placed in a hypotonic environment, it will:
shrink (get smaller)
swell (get bigger)
stay the same
none of the above
3.
Exocytosis is a:
mechanism by which cells ingest other cells
transport process in which vesicles are formed from pouches in the cell membrane
a way for cells to release large molecules and wastes
none of the above
4.
How are cell membrane’s best described? (READ choices carefully!)
a double layer of phospholipid molecules with hydrophobic tails directed towards the cytoplasm of the cell
a single layer of phospholipid molecules with water molecules attached along one side
a double layer of phospholipid molecules with hydrophilic heads directed towards each other.
A double layer of phospholipid molecules with hydrophobic tails oriented towards each other.
5.
For diffusion to occur, there must be:
a gradient
energy
ATP
water
6.
In reference to diffusion, “passive” really means:
energy IS required
without a membrane
energy is NOT required
in the air
7.
Solutes (like salt) assisted by a carrier or peripheral protein may cross a semipermeable membrane by which process?
facilitated diffusion
osmosis
simple diffusion
endocytosis
8.
The diffusion of water molecules across a semipermeable membrane is termed:
simple diffusion
facilitated diffusion
hydrolysis
osmosis
9.
If a red blood cell is taken from the body and placed in a hypertonic solution, what happens to the cells?
The cell swells (gets bigger) and burst because water is moving into the cell
The cell shrivels up (gets smaller) because water is leaving the cell
The cell remains unchanged due to equal solute concentrations inside and outside the cell
They become white blood cells
10.
What is active transport?
diffusion of molecules within a cell
movement of molecules into or out of a cell against a concentration gradient
movement of molecules into or out of a cell down a concentration gradient
rapid movement of molecules in solution
11.
A cell is placed in an isotonic solution. Which statement is TRUE about water movement?
net water movement will be into the cell because there is more water outside than inside
net movement will be out of the cell because there is more solutes outside the cell
no water will move into or out of the cell
water will move into and out of the cell at equal rates
12.
Solutions that cause water to enter cells by osmosis are termed:
isotonic
hypertonic
hypotonic
homeostasis
13.
What does a cell use exocytosis for?
to move away from danger
to release or remove substances from the cell
to bring nutrients in
to create new cells
14.
A cell controls what enters and leaves itself in order to maintain:
communication with other cells
move through its environment
create new cells
homeostasis
15.
During the “egg lab” what happened to the egg after we let it sit in vinegar for a day?
the egg became cooked
the egg broke into pieces
the shell was removed
syrup went into the egg
16.
During the “egg lab”, what happened after the egg sat in water overnight?
the egg got bigger
the shell was removed
the egg shrunk
there was more water in the cup
17.
During the “egg lab”, what happened after the egg sat in syrup overnight?
the syrup got runny (more watery)
the egg lost mass
the egg gained mass
both A and B
18.
The “water loving” portion of the cell membrane:
contains the lipids
contains the phosphates
contains the "tails"
none of these
19.
The “water fearing” portion of the cell membrane:
contains the lipids
contains the phosphates
contains the "heads"
none of these
20.
A ___________ is the difference between the concentration of a particular molecule in one area and the concentration in an adjacent area.
semipermeable membrane
bulk transport
osmosis
concentration gradient
21.
The cell membrane is described as a fluid mosaic. It is said to be a mosaic because:
individual phosphates and proteins can move freely
because of the pattern produced by the scattered proteins
because of the “water fearing” ends
because of the “water loving” ends
22.
Look at the picture below, in which direction will diffusion take place?

solutes will move into the cell
solutes will move out of the cell
water will not move
water will move out of cell


HELP TEST