Bell work
1. Take out a sheet of notebook paper and put your name on
top.
2. On the next line, write today’s date.
3. On the next line (or lines), copy today’s bell work questions
(below).
4. After writing the questions, write your answer in complete
sentences.
5. After we review the answer to today’s question, correct your
answer if needed, and place your bell work into your folder. We
will use the same sheet of paper all week. All bell work from this
week must be on one sheet of paper. Bell work will be collected
on Friday.
What is a cell?
Date
Learning Goal
Objective
Essential
Question
1/27/14
Explain the role of cell
membranes as a highly
selective barrier
(passive and active
transport).
Differentiate types of
movement across
plasma membranes.
What features of
molecules determine
how they are
transported through
cells?
Vocabulary
diffusion, osmosis,
active transport, passive
transport
Ticket Out: Activity results
Subject
Bell work
Agenda
Zoology
What is a cell?
•Introduce homework
•Transport across
plasma membranes
PPT
•Reading Notes (pg 1018)
•Foldable: term,
definition, picture
•Endocytosis activity
Homework: Article review: The Origin of Eukaryotic Cells, Due Friday 1/31
Bell work
 What
is a cell?
The simplest organization of matter that
exhibits all of the properties of life
If you were absent on Friday
I
emailed to you what you missed.
 Make sure that you have completed all of
the bell work.
 All assignments from when you were here,
including completed bell work come in to
me today.
 You have 5 days to turn in assignments
from the day that you were absent.
AS Biology, Cell membranes and
Transport
4
Homework
 The
Origin of Eukaryotic Cells
 Read the article
 Summary





Article review worksheet format is on Moodle
Use your own paper
3 vocabulary terms – defined
Article summary – who, what, where, when,
how, why – as appropriate
Conclusion – what was the point?
What Are Cells?
Prokaryote vs. Eukaryote
Prokaryote – lack nucleus and other membrane-bound organelles
Eukaryote – has membrane-bound nucleus containing the DNA, as well as
many other structures called organelles.
Why are most cells small?
• 1 – The ratio of the volume of the cells nucleus to the
volume of its cytoplasm must not be so small that the
nucleus cannot control the cytoplasm.
• 2 – As the radius of a cell lengthens, the cell volume
increases more rapidly than cell surface area.
– The cell would need more nutrients and would have more waste
to get rid of.
– If the volume increases too much there wouldn’t be enough
surface area of the cell membrane to allow for that exchange of
nutrients and wastes
The relationship between surface area and volume: As the radius of the
sphere increases, it’s volume increases more rapidly than its surface
area.
WAYS MOLECULES MOVE
http://www.biology4kids.com/files/cell_main.html
Diffusion
http://lhs.lps.org/staff/sputnam/Biology/U3Cell/diffusion_1.png
Animatioin from: http://www.biologycorner.com/resources/diffusion-animated.gif
Molecules move
FROM
A LOT
_______“where
there’s _______”
to
NOT
____“where
there’s _______”
DIFFUSION across a space
Happens anytime there is a
__________
DIFFERENCE in concentration in
one place compared to another
Concentration gradient
= ________________________
DIFFUSION across a SPACE
Molecules move automatically _______
DOWN
the concentration gradient _______
an
from
area of _______
Higher concentration ____
to an
area of ________
concentration
Lower
• EXAMPLES
Blue dye in beaker demo,
Someone making popcorn/grilling out
Strong perfume,
Bad smell in room
http://leighhouse.typepad.com/blog/images/kool_aid.jpg
http://www.swapmeetdave.com/Humor/Farts.htm
DIFFUSION across a space
Diffusion continues until the concentration
equal everywhere
is ________________
in space
Equilibrium
= ________________________
http://lhs.lps.org/staff/sputnam/Biology/U3Cell/diffusion_1.png
Molecules
need to
move
across
membranes
in cells
Image modiified from: http://www.accessexcellence.org/AB/GG/importProt.html
across
Diffusion can happen ________
a
membrane
_____________
in a cell, too
…as long as membrane will let the molecule
pass through
_________________
CELL EXAMPLE:
DIFFUSION automatically moves oxygen
from HIGHER concentration (in lungs)
to a LOWER concentration (in blood)
CO2 automatically moves
from where there is a
HIGHER concentration
(in blood) to where there
is a lower concentration
(in lungs)
http://www.le.ac.uk/pa/teach/va/anatomy/case2/2_2.html
PROBLEM for CELLS?
Diffusion only moves molecules
from high concentration to low
concentration.
What if cell needs to move a
AGAINST the
molecule _________
CONCENTRATION
GRADIENT?
_______________
(LOWER  HIGHER)
Cell example:
Want to put MORE glucose
into mitochondria when there is
already glucose in there
Image from: http://www.biologyclass.net/mitochondria.jpg
Video from: http://www.southtexascollege.edu/tdehne/BC_ShockwaveAnimations/08SWF-MembraneStructureAndFunct/08-02-MembraneStructure.swf
PROBLEM for
Cells?
Cell membranes
are
SELECTIVELY
PERMEABLE
What if a cell needs to
LARGE or ______
POLAR
move _____
molecules
that can’t get
through the
membrane?
http://www.d.umn.edu/~sdowning/Membranes/membraneImages/jpegimages/diffusionmedium.jpg
PROBLEM for CELLS?
Diffusion happens very slowly
What if cell needs to move
FAST
molecules really _______?
(can’t wait for it to diffuse)
Cell example:
Movement of
Na + & K+ ions
required to send
nerve signals
http://www.steve.gb.com/images/science/neuron.png
WAY to
Cells need a ____
HELP molecules across
____
cell membranes that
can’t go across by
_______
themselves
___________
Kidspiration by: Riedell
PASSIVE Transport
Kinds of ________
•__________________________________
Diffusion
•Facilitated
Diffusion
___________________________________
•Carriers
_______________________________
•Channels
_______________________________
DIFFUSION across a membrane
DIFFERENCE
Happens anytime there is a __________
in _____________
concentration on one side of the
membrane compared to the other
http://student.ccbcmd.edu/~gkaiser/biotutorials/eustruct/passiveanim.html
http://bioweb.wku.edu/courses/Biol22000/10Biomembranes/images/membrane.gif
DIFFUSION
PASSIVE
• No energy required = _______
DOWN concentration gradient
• Moves _______
from ___________________
HIGHER to LOWER
• Works for any molecules that can pass through
the membrane
• Example of molecules that move this way in
cells:
OXYGEN
Carbon dioxide
________ & ____________
FACILITATED DIFFUSION
membrane proteins to help
uses _______________
molecules across
2 kinds of proteins help:
Carriers
Channels
_________
& ____________
Animations from: http://bio.winona.edu/berg/ANIMTNS/facdifan.gif
http://www2.uic.edu/~myilma1/ionchannel.gif
Facilitated Diffusion with
CARRIER PROTEINS
Carrier protein
grabs molecule,
changes
shape
_________,
and
flips across to
other side like a
revolving door
Animation from: http://bio.winona.edu/berg/ANIMTNS/facdifan.gif
http://www.gobananas.co.uk/edinburgh-stag-party/enquiry/index.htm
FACILITATED DIFFUSION
with CHANNELS
http://bio.winona.edu/berg/ANIMTNS/voltgate.htm
Membrane
proteins
create a
tunnel through
which molecules
can pass
ION CHANNELS allow________
charged ions
_______________
hydrophobic
to get past the ____________
center
FACILITATED DIFFUSION
with CHANNELS
polar
________
Aquaporin proteins allow ________
WATER molecules to get past
_________
hydrophobic middle of cell
the __________
membrane.
http://www.spps.kvl.dk/news/0507/Lund4.jpg
FACILITATED DIFFUSION
with CHANNELS
The movement of water molecules
across a cell membrane is called
OSMOSIS
______________
http://student.ccbcmd.edu/~gkaiser/biotutorials/eustruct/channelanim.html
ALL KINDS OF
FACILITATED DIFFUSION
PASSIVE
• No energy required = _____________
DOWN
• Moves ________ concentration gradient
HIGHER to LOWER
from ________________________
Membrane proteins
• ___________________
help molecules
get across membrane
EXAMPLES OF FACILITATED
DIFFUSION IN CELLS
• CARRIER PROTEINS
GLUCOSE
• ION CHANNELS
Na+ , Cl- , Ca++ ,
K+
• AQUAPORINS (OSMOSIS)
WATER
Kidspiration by: Riedell
ACTIVE
Kinds of ________Transport
• ________________________________________
PUMPS
•Sodium-Potassium
__________________________________
•Proton
________________________________
•Vesicles
___________________________________
•Endocytosis
________________________________
•Exocytosis
________________________________
+
Na
and K
+
Animation from: http://www.lionden.com/cell_animations.htm
PUMP
SODIUM-POTASSIUM PUMP
ACTIVE transport
• ___________
ATP
(requires energy from ______)
low concentration
• Can move molecules from _____
high
to ______
• Special just for Na+ and K
+
ions
membrane proteins called
• Uses _______________________
____________
to move molecules
pumps
• Example: nerve cells
Na+ is pumped out of cells at same time
K + is taken into cells
PROTON PUMP
Moves
Protons
across
membrane
H+ ions
= ___
PROTON PUMP
ACTIVE transport
• ___________
ATP
(requires energy from ______)
low concentration
• Can move molecules from _____
to ________
high
• Special just for H+ ions
Protein pumps to move molecules
• Uses integral ________________
Examples:
• Lysosomes need acidic conditions for digestion
• Photosynthesis/Respiration
ACTIVE TRANSPORT
with VESICLES
VESICLES are small membrane sacs that
___________
pinch off of cell membranes used by cells for
transporting molecules
Used for transporting molecules:
ENDOCYTOSIS
If entering the cell = ______________
If exiting the cell = _______________
EXOCYTOSIS
http://academic.brooklyn.cuny.edu/biology/bio4fv/page/cell-movement.html
http://academic.brooklyn.cuny.edu/biology/bio4fv/page/exocy.htm
2 KINDS of ENDOCYTOSIS
for taking substances into cell
If taking in:
PINOCYTOSIS
fluid or small molecules =_________________
PHAGOCYTOSIS
large particles or whole cells =______________
Animation from: http://academic.brooklyn.cuny.edu/biology/bio4fv/page/endocytb.htm
ENDOCYTOSIS
Substances taken into cell
ACTIVE transport (requires________)
energy
• __________
VESICLES
• Uses ______________
to carry substances
low concentration
• Can move molecules from _____
to ______
high
Examples in cells:
– one celled organisms eat this way
– white blood cells get rid of bacteria this way
ENDOCYTOSIS
Animation from: http://academic.brooklyn.cuny.edu/biology/bio4fv/page/cell-movement.html
Protist eating
another
http://www.accs.net/users/kriel/chapter%20nine/
PHAGOCYTOSIS
White
blood cell
___________
bacteria
engulfing _______
WHITE BLOOD CELL
ENGULFING BACTERIA
(Phagocytosis)
http://fig.cox.miami.edu/~cmallery/255/255ion/fig14x28.jpg
EXOCYTOSIS
Substances released outside of cell
ACTIVE transport (requires________)
energy
• __________
VESICLES
• Uses ______________
to carry substances
low concentration
• Can move molecules from _____
to ______
high
• Examples in cells:
– _________
GOLGI release packaged proteins
this way
Video: http://www.southtexascollege.edu/tdehne/BC_ShockwaveAnimations/07SWF-TourOfTheCell/07-16-EndomembraneSystem.swf
GOLGI BODIES USE EXOCYTOSIS
Animation from: http://www.franklincollege.edu/bioweb/A&Pfiles/week04.html
INSULIN being released by
pancreas cells using exocytosis
http://fig.cox.miami.edu/~cmallery/255/255ion/fig14x26.jpg
VOCAB
_____________
SOLUTE
= substance that is
dissolved in a solvent to make a solution
SOLVENT = substance in which a
_____________
solute is dissolved
http://www.makash.ac.il/h_school/hst/hstsb/chem/luach/dissolve.jpg
Images by Riedell
__________________
CONCENTRATION = mass of
a solute in a given volume of
solution
MORE molecules there are in a given
The _______
volume the ____________the
concentration
GREATER
Use new vocab to make Koolaid
Koolaid powder
sugar
Solutes = ______________&
__________
Water
Solvent = ____________
solution
Koolaid drink = ______________
http://www.makash.ac.il/h_school/hst/hstsb/chem/luach/dissolve.jpg
What if there is a difference in
concentration but solute
molecules can’t move across a
membrane?
WATER will move
until concentration
reaches equilibrium
Animation: http://www.ouhscphysio.org/humanphys/animations/osmosis1.swf
http://faculty.etsu.edu/currie/images/osmosis1.jpg
Solute concentration
Lower outside
than inside
Equal outside
and inside
Greater outside
than inside
HYPOTONIC
ISOTONIC
HYPERTONIC
What will happen to an animal cell
placed in different solutions?
Remember:
Cells try to “maintain stable
internal conditions =
HOMEOSTASIS
____________________
http://bioweb.wku.edu/courses/biol121/Osmosis/Osmosis.asp
So an animal cell in
ISOTONIC conditions
stays same size
Water entering = water leaving
If cells can’t maintain
“stable internal conditions” . . .
damage can result and cells can die.
http://www.the-aps.org/education/lot/cell/Quiz.htm
Animation from: http://www.ouhscphysio.org/humanphys/animations/osmosis3.swf
OSMOSIS
HYPOTONIC:
Concentration outside cell is
________________
inside the cell
LESS THAN
More water enters than leaves cell so cell
will ___________________
swell and possibly burst
Animation from: http://www.ouhscphysio.org/humanphys/animations/osmosis4.swf
OSMOSIS
HYPERTONIC: Concentration outside cell is
____________________
inside cell
GREATER THAN
More water leaves cell than enters
so cell ____________
shrinks
http://www.stchs.org/science/courses/sbioa/metenergy/bloodcells.gif
Animal cells
= CYTOLYSIS
_________
= CRENATION
__________
SO WHAT?
Bath water is
________________
hypotonic
compared to you
Sitting in the bathtub causes your fingers
and toes to wrinkle up when water
________
enters your skin cells by osmosis
Grocery stores spray water on
their veggies to “plump them up”
http://www.painetworks.com/photos/gt/gt0461.JPG
SO WHAT?
Endocytosis Activity
• Materials:
–
–
–
–
Paper lunch bag
String
Scissors
Marble
69
Endocytosis Activity
• Procedure
– The paper part of the bag is the cell membrane
– The air inside the bag is the cytoplasm
– Goal – How to get the large molecule (marble) inside the
cell (bag) without exposing the inside of the bag to the
air.
– You cannot put the marble through the top of the bag,
but you can stick your hand through the top of the bag.
– You will need to use all of the supplies given
70
copyright cmassengale
71
FOLDABLE
• Different types of movement across plasma
membranes (page 15).
–
–
–
–
–
–
–
Simple diffusion
Facilitated diffusion
Osmosis
Filtration
Active transport
Endocytosis
Exocytosis
• For each type of movement, include:
– Term
– Definition
– Drawing
72