AP BIOLOGY Review
Campbell Chapter 7
Plants that can tolerate extreme cold have a
higher percentage of phospholipids with
unsaturated
______________
fatty acid tails.
SATURATED
UNSATURATED
Cholesterol can be called a “temperature buffer”
because at higher temperatures (like body temp) it
less fluid by restraining
makes the phospholipids ________
their movements.
less
more
At lower temperatures cholesterol hinders the close
packing of phospholipids so it __________
lowers the temperature
required for membranes to solidify.
lowers raises
Proteins that penetrate the hydrophobic core of
Integral proteins
a membrane are called _________________
Membrane proteins with carbohydrates attached
are called ____________________
glycoproteins
Living things must control the balance of water
and ions in their tissues. This is called
Osmoregulation (kind of homeostasis)
_____________________
http://www.microscopy-uk.org.uk/mag/imgjun99/vidjun1.gif
If a Paramecium were to swim from a
hypotonic environment to an isotonic
one, would the activity of its contractile
vacuole increase or decrease?
Campbell Concept check 7.3
It would decrease, because less water would be entering
An environment in which the concentration of
solutes outside and inside the cell are equal is
isotonic
called _________________
An animal cell placed in this type of environment
will _____________________
stay the same size
swell & burst
shrink
stay the same size
The diffusion of water across a semi-permeable
osmosis
membrane is called _________________
An environment in which the concentration of
solutes is greater outside the cell than inside is
called _________________
hypertonic
An animal cell placed in this type of environment
will _____________________
shrink
swell & burst
shrink
stay the same size
Membrane transport that requires energy is called
ACTIVE
________________
The Na+-K+ pump in animals causes the
cytoplasm inside cells to be more ___________
negative
than the surrounding extracellular fluid
negative positive
Membrane lipids with carbohydrates attached are
called ____________________
glycolipids
In passive transport molecules always move
DOWN
___________
their concentration gradient.
down up
An environment in which the concentration of
solutes outside is less than inside the cell is
hypotonic
called _________________
An animal cell placed in this type of environment
swell and burst
will _____________________
swell & burst
shrink
stay the same size
Channel proteins that facilitate the movement of
water across cell membranes are called
aquaporins
___________________
channel
Transport proteins called _____________
proteins
function by forminng a hydrophilic tunnel that
allows charged molecules or ions to pass through
the hydrophobic portion of a cell membrane.
carrier
Transport proteins called _____________
proteins
hold on to their passenger molecules, change
shape, and shuttle them across the membrane.
As a cell grows, its plasma membrane expands
Exocytosis; when vesicles fuse with membrane
via ___________________.
endocytosis
exocytosis
they become part of the
membrane
Campbell Concept check 7.5
Name 3 kinds of passive transport
Osmosis, diffusion, facilitated diffusion
Name 3 kinds of active transport
Na+-K+ pump, co-transport, bulk transport,
endocytosis, pinocytosis, phagocytosis,
receptor mediated endocytosis, exocytosis
Ion channels that open or close in response to a
gated
signal are called ___________________
Name the kind of transport
Facilitated diffusion
with an Ion channel
Name the kind of transport
Facilitated diffusion with a
carrier
A transport protein that generates voltage across
a membrane is called an
________________________
Electrogenic pump
When nerve cells establish a voltage across their
membrane with a sodium-potassium pump,
does this pump use ATP or produce ATP?
Campbell Concept check
The pump uses ATP.
To establish a voltage, ions would have to be
pumped against their gradient,
which requires energy
http://www.biologymad.com/NervousSystem/nakpump.gif
Name this kind of transport
Sodium-potassium pump
Give an example of bulk transport
Endocytosis
(phagocytosis, pinocytosis, receptor mediated endocytosis)
Exocytosis
Animation from: http://academic.brooklyn.cuny.edu/biology/bio4fv/page/cell-movement.html
Name this kind of transport
used by bacteria to take in
food or white blood cells
to engulf bacteria
phagocytosis
http://www.accs.net/users/kriel/chapter%20nine/
If this vesicle is releasing
products outside the cell,
this type of transport is called
exocytosis
________________________
If this vesicle is bringing
small molecules & fluids
into the cell, this type
of transport is called
______________________
pinocytosis
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBooktransp.html#Vesicle-mediated%20transport
Animation from: http://www.sp.uconn.edu/~terry/images/anim/fluidmem.gif
Click here to
See Fluidity
The currently accepted model that describes cell
membranes as the arrangement of constantly moving
proteins embedded in or attached to a bilayer or
phospholipids is called the
Fluid mosaic model
______________________________________
http://academic.brooklyn.cuny.edu/biology/bio4fv/page/rectpr.htm
Name this kind of
transport that enables the
cell to acquire bulk quantities
of specific substances
Receptor mediated
endocytosis
The molecules that bind to these receptors are
ligands
called _____________________
Give an example of a molecule that moves into
Cholesterol
cells in this way _________________
LDL ligands bind receptors and attached
cholesterol is taken into cell
Name the kind of transport that moves
molecules from high concentration to low
across a membrane without using energy
and without the help of any carriers or
vesicles
DIFFUSION
To send a signal, a neuron may carry out exocytosis of
chemical signals that are recognized by a 2nd neuron. In
some cases, the 1st neuron ends the signal by taking up
the signaling molecules by endocytosis.
Would you expect this to occur by pinocytosis or by
receptor mediated endocytosis? EXPLAIN
Campbell Concept check
Receptor mediated endocytosis because in this
case one specific molecule needs to be taken up at
a particular time; pinocytosis takes up molecules
in a non-specific manner
http://www.uic.edu/classes/bios/bios100/lecturesf04am/sucrosepump.jpg
Name this kind of transport in which transport of
one substance DOWN its gradient is coupled to the
movement of another moving UP the gradient.
cotransport
http://www.biologymad.com/NervousSystem/nakpump.gif
Explain why the
sodium-potassium pump
is NOT considered a
cotransporter.
Campbell concept check 7.4
Each ion is being transported
against its gradient. If either ion were flowing DOWN its
electrochemical gradient, this would be Co-transport.
Co-transport couples the movement
of one substance down its gradient with one moving up.
Name the kind of transport used by Golgi bodies
in secretory cells to export their products.
exocytosis
Name the kind of transport used by cholesterol
to enter cells
Receptor mediated endocytosis
Name the molecule that provides energy for
active transport
ATP
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBooktransp.html#Vesicle-mediated%20transport
The swelling and bursting of animal cells when placed in a
cytolysis
hypotonic environment is called _________________
The shrinking and shriveling up of animal cells when placed
in a hypertonic environment is called ___________________
crenation
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBooktransp.html#Vesicle-mediated%20transport
The swelling of plant cells when placed in a hypotonic
increase
environment ______________
the osmotic pressure inside
the cell
increases decreases
turgid
We would say the cell is ___________
turgid
flaccid
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBooktransp.html#Vesicle-mediated%20transport
The pulling away of the cell membrane from the cell wall in
plant cells when placed in a hypertonic environment is
plasmolysis
called _______________________
A plant cell that has lost water and is “limp” is called
_____________________
flaccid
Carrier proteins
like this one are
______________proteins.
integral
Integral
peripheral
Carbon dioxide and oxygen move
across membranes in cells by
Diffusion
_________________
Kind of endocytosis used to take in
large particles or whole cells.
phagocytosis
The voltage across a membrane is
called __________________
membrane potential
When you sit in the
bathtub, your fingers
get wrinkly because
of the water entering
your skin cells. The
bathtub water is a
____________
hypotonic
solution compared to
your skin cells
Hypotonic
isotonic
hypertonic
A membrane that lets certain molecules
pass through and not others is called
_______________
Semi permeable OR
selectively permeable
Name a kind of transport that uses
vesicles to move substances across
a membrane
Pinocytosis, phagocytosis,
Exocytosis, endocytosis
Name the kind of transport that
moves WATER across cell membranes
OSMOSIS
A freshwater fish has
about 1% salt in his
body. Freshwater is
close to 0% salt.
Will water move into or
out of this kind of
fish?
More solute
molecules inside
the fish’s cells
than in the
freshwater.
(HYPOTONIC)
Water will move
INTO the fish
Which of the following factors would tend to increase
membrane fluidity?
A A. a greater proportion of unsaturated phospholipids
B. a greater proportion of saturated phospholipids
C. a lower temperature
D. a relatively high protein content in the membrane
E. a greater proportion of relatively large glycolipids
compared to lipids having smaller molecular masses
Campbell Concept check
Which organelle
makes the
ATP used to
run the Na + K+ pump?
mitochondria
Type of endocytosis in which cells
take in small molecules or fluids
pinocytosis
The white circles
stand for oxygen
molecules.
Use what you know
about diffusion of
molecules to predict
which way the
oxygen will move.
Diffusion moves molecules from
high concentration to low so…
from the lungs into the blood
Based on the model of sucrose uptake in the figure below, which of the
following experimental treatments would increase the rate of sucrose transport
into the cell?
A. decreasing extracellular sucrose concentration
B B. increasing extracellular pH
C. decreasing cytoplasmic pH
D. adding an inhibitor that block the regeneration of ATP
E. adding a substance that make the membrane more permeable to
hydrogen ions
Campbell Concept check
This type of transport which opens
in response to a signal and forms a
“tunnel” through the membrane to let
ions in and out is called a(n)
___________________
Gated ion channel
Tell if the transport is ACTIVE or PASSIVE
PASSIVE
Facilitated diffusion ___________________
Osmosis ____________________
PASSIVE
Na + - K+ pump ____________________
ACTIVE
Diffusion ____________________
PASSIVE
Endocytosis _______________________
ACTIVE
ACTIVE
Exocytosis ________________________
Ion channels ________________________
PASSIVE
Proton pumps ______________________
ACTIVE
Aquaporins _____________________
PASSIVE
Match the picture with the kind of
transport
FACILITATED
DIFFUSION
(carrier)
DIFFUSION
Match the picture with the kind of
transport
EXOCYTOSIS
INSIDE
CELL
OUTSIDE
CELL
Substance is put in a
vesicle and transported
up to the cell membrane
and released OUTSIDE
Name an organelle that uses this
kind of transport Golgi Bodies
In what way do the various membranes of a eukaryotic cell
differ?
A. Phospholipids are found only in certain membranes
B B. Certain proteins are unique to each membrane
C. Only certain membranes of the cell are selectively
permeable.
D. Only certain membranes are constructed from
amphipathic molecules
E. Some membranes have hydrophobic surfaces
exposed to the cytoplasm; while others have
hydrophilic surfaces facing the cytoplasm.
Campbell Concept check
Match the picture with the kind of
transport
Na+ - K + pump
Energy from ATP is used to move 3 Na + ions OUT of
the cell and carry 2 K + ions INTO the cell
This pump is the main electrogenic
pump used in ______________
cells.
animal
plant
animal
Which of the following processes includes all the others?
A. osmosis
B. diffusion of a solute across a membrane
C. facilitated diffusion
D. passive transport
E. transport of an ion down its electrochemical gradient
D; diffusion, osmosis, facilitated diffusion, ion
channels are all kinds of passive transport
Campbell Concept check
Match the picture with the kind of
transport
ENDOCYTOSIS
Substance is transported
INTO cell inside a vesicle
If what is moving into the cell is a small
molecules and fluids
this would be called __________________
PINOCYTOSIS
LABEL THE TONICITY DIAGRAMS
HYPERTONIC
ISOTONIC
HYPOTONIC
Name the two types of transport proteins that
carry out facilitated diffusion
Channels and carriers
Which of these would increase membrane
fluidity?
A a) greater proportion of unsaturated phospholipids
b) greater proportion of saturated phospholipids
c) a lower temperature
d) relatively high protein content in membrane
e) greater proportion of relatively large glycolipids
compared to lipids having smaller molecular
masses
Campbell Ch 7 self quiz
Diffusion is a spontaneous process in which
down their concentration
molecules move _______
gradient.
up down
Channel proteins
Aquaporins are ______________________
for water molecules
a) carrier proteins
b) channel proteins
c) active cotransporters
d) ligands
e) a kind of Na+-K+ pump
Name the genetic disorder you learned about in
BIO I in which there is a mutation in the protein
that transports Cl- ions causing a build up of
thick mucous in the lungs and digestive organs
Image from: BIOLOGY by Miller and Levine; Prentice Hall Publishing ©2006
Cystic fibrosis
Explain why plant cells don’t undergo cytolysis in
hypotonic environments but animal cells do.
Cell wall is rigid and keeps them from bursting
Give an example of an amphipathic molecule.
Phospholipids have both hydrophobic and
hydrophilic regions; so do many proteins
Method of splitting a cell membrane along the
middle of the phospholipid bilayer
Freeze fracture
Name this cell model
which proposed that
membranes were
“sandwiches” of
phospholipids between
two layers of
hydrophilic
proteins
Davson-Danielli model
A mole of table sugar and a mole of vitamin C
are equal in their
A. mass in daltons
C. A mole of anything
B. mass in grams
C. number of molecules contains 6.02 X 10 -12
molecules.
D. number of atoms
E. volume
Campbell Self quiz
A _______________
amphipathic molecule has both a hydrophilic
region and a hydrophobic region.
Selectively or semi- permeable
Cell membranes are called _____________________
because they allow certain substances to pass through,
but keep others out.
The proton pump is the main electrogenic pump
plant
in ________________
cells.
plant animal
Membrane proteins that span the membrane
touching both sides are called
transmembrane proteins
_________________
Name the molecules which can be attached to
proteins or lipids in cell membranes and are
involved in cell recognition carbohydrates
How would you make a 0.5 M solution of
sodium chloride?
Campbell Concept Check 3.2
(The atomic mass of Na is 23 daltons and Cl is 35.5
daltons)
58.5 daltons
Mass of 1 mole of NaCl = _______
(23 + 35.5)
58.5 g NaCl X 0.5 moles = _______
29.25 g/L
1 mole
1L
Dissolve 29.25 g of NaCl in water to make 1 L of
solution
How many grams of acetic acid (C2H4O2) would you
use to make 10 L of a 0.1 M aqueous solution of
acetic acid?
(The atomic masses in daltons are approximately 12 for C, 16 for O, and 1
Campbell Chapter Self Quiz
for H)
A. 10.0 g
B. 0.1 g
C. 6.0 g
D. 60.0 g
E. 0.6 g
Mass of 1 mole of acetic acid
C = 2 X 12 = 24 daltons
H = 4 X 1 = 4 daltons
O = 2 X 16 = 32 daltons
60 daltons
60.0 g X 0.1 moles = 6 g/L X 10 L = 60.0 g
1 mole
1L
60.0 g of acetic acid and add water to make 10 L of
solution (D is correct)
Which type of transport maintains the membrane
potential in animal cells?
Sodium-potassium pump
Molecules that bind specifically to a receptor site
ligands
on another molecule are called ____________
Name the transport process you learned about in
which ligands are involved in the uptake of
molecules
Receptor mediated endocytosis
Electrogenic pumps create voltage across cell
membranes making the cytoplasm more
negative
_______________
than the extracellular fluid.
negative positive
The water potential ψ for pure water at
zero
atmospheric pressure is ______
decreases the water
The addition of solutes ___________
potential.
increases decreases
USE lower and higher to complete the following:
higher
Water always moves from an area with ________
lower water
water potential to an area with _______
potential.
Water with solutes dissolved in it will have a
lower
______________
water potential than plain water.
According to the fluid mosaic model of membrane
structure, proteins of the membrane are mostly
A. spread in a continuous layer over the inner and
outer surfaces of the membrane
B. confined to the hydrophobic core of the membrane
C C. embedded in a lipid bilayer
D. randomly oriented in the membrane with not fixed
inside-outside polarity
E. free to depart from the fluid membrane and dissolve
in the surrounding solution
Campbell Concept check
An artificial cell consisting of an aqueous solution enclosed in a
selectively permeable membrane has just been immersed in a beaker
containing a different solution.
The membrane is permeable to water and to the simple sugars glucose
and fructose, but completely impermeable to the disachride sucrose.
Which solute(s) will exhibit a net diffusion into the cell?
fructose
Which solute(s) will exhibit a net diffusion out of the cell?
glucose
An artificial cell consisting of an aqueous solution enclosed in a
selectively permeable membrane has just been immersed in a beaker
containing a different solution.
The membrane is permeable to water and to the simple sugars glucose
and fructose, but completely impermeable to the disachride sucrose.
Campbell Concept check
Which solution-the cell or the environment- is hypertonic to
the other?
Cell (0.05 M) is hypertonic to the environment (0.03 M)
In which direction will there be a net osmotic movement of
water? Water will move into the cell
After the cell is placed in the beaker, which of the following
changes will occur?
A. The artificial cell will become more flaccid.
B. The artificial cell will become more turgid.
C. Some water molecules will flow out of the cell, but the majority will flow in.
D. The membrane potential will decrease
E. In spite of the inability of sucrose to cross the cell membrane, eventually the two
solutions will become isotonic.
B, C, E are correct
Campbell Concept check