Border Control!
Active & Passive Transport
across cell lines!
After this lecture you will be able to…
Part 1: Understand Diffusion and
concentration gradients
Part 2: Understand types of Passive Transport
(Diffusion, Osmosis, facilitated diffusion)
Part 3: Understand types of Active Transport
Diffusion
http://lhs.lps.org/staff/sputnam/Biology/U3Cell/diffusion_1.png
Animation 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 modified 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
_________________
Video from: http://www.southtexascollege.edu/tdehne/BC_ShockwaveAnimations/08SWF-MembraneStructureAndFunct/08-02-MembraneStructure.swf
SELECTIVELY
PERMEABLE
(Semi-permeable)
See a movie
http://life.nthu.edu.tw/~d857401/advance.html
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
Kidspiration by: Riedell
PASSIVE Transport
Kinds of ________
•__________________________________
Diffusion
•Osmosis
___________________________________
•Facilitated
Diffusion
___________________________________
DIFFUSION across a membrane
DIFFERENCE
Happens anytime there is a __________
in _____________
concentration on one side of the
membrane compared to the other
Molecules that move by
diffusion across membranes
in cells:
______________
OXYGEN
______________
CARBON DIOXIDE
http://www.lionden.com/cell_animations.htm
See diffusion
animation
OSMOSIS
= SPECIAL KIND OF DIFFUSION
IMAGE by RIEDELL
OSMOSIS
____________
See osmosis
animation
DIFFUSION
__________
Movement of molecules across a
Semi-permeable membrane
_________________
lower
from ______
Higher concentration to _____
VOCAB
_____________
SOLUTE
= substance that is
dissolved in a solvent to make a solution
SOLVENT = substance in which a
_____________
solute is dissolved
EX:
Koolaid powder = solute
Water = solvent
Koolaid drink = solution
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
See a video clip about
OSMOSIS -7B
Animation: http://www.ouhscphysio.org/humanphys/animations/osmosis1.swf
See an animation
Osmosis1
http://faculty.etsu.edu/currie/images/osmosis1.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
**Write: Water can
move across freely, so it
tries to “help out” and
moves over to the high
solute side to dilute it.
Animation from: http://www.ouhscphysio.org/humanphys/animations/osmosis4.swf
OSMOSIS
See an animation
OSMOSIS 4
HYPERTONIC: Concentration outside cell is
____________________
inside cell
GREATER THAN
More water leaves cell than enters
so cell ____________
shrinks
Cell in Hypertonic Solution
15% NaCL
85% H2O
ENVIRONMENT
CELL
5% NaCL
95% H2O
What is the direction of water movement?
Animation from: http://www.ouhscphysio.org/humanphys/animations/osmosis3.swf
OSMOSIS
See an animation
Osmosis3
HYPOTONIC:
Concentration outside cell is
________________
LESS THAN inside the cell
More water enters than leaves cell so cell
will ___________________
Swell and possibly burst
Cell in Hypotonic Solution
10% NaCL
90% H2O
CELL
20% NaCL
80% H2O
What is the direction of water movement?
OSMOSIS
ISOTONIC:
EQUALS
Concentration outside cell __________
concentration inside cell
Water entering = water leaving
STAYS THE SAME SIZE
so cell _____________________
Cell in Isotonic Solution
10% NaCL
90% H2O
ENVIRONMENT
CELL
10% NaCL
90% H2O
NO NET
MOVEMENT
What is the direction of water movement?
equilibrium
The cell is at _______________.
Isotonic Solution
NO NET
MOVEMENT OF
H2O (equal amounts
entering & leaving)
Hypotonic
Solution
Cell Swells &
may burst
Hypertonic
Solution
Cell shrivels up
Animal cells
http://www.stchs.org/science/courses/sbioa/metenergy/bloodcells.gif
Osmosis in Red Blood Cells
Isotonic
Hypotonic
Hypertonic
Facilitated Diffusion
Carrier proteins help diffusion go faster
_______
FACILITATED DIFFUSION
• No energy required = __________________
PASSIVE
DOWN concentration gradient
• Moves _________
from ________________________
HIGHER to LOWER
Membrane proteins
• _____________________
grab molecule,
change shape, and flip to other side
(Like a revolving door)
• Molecules that move this way in cells:
GLUCOSE
_______________________
Facilitated Diffusion
Animation from: http://bio.winona.edu/berg/ANIMTNS/facdifan.gif
Kidspiration by: Riedell
BUT….
What if a cell needs to
LARGE or ______
POLAR
move _____
molecules?
http://www.d.umn.edu/~sdowning/Membranes/membraneImages/jpegimages/diffusionmedium.jpg
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
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 ____
HELP
We need a ____
molecules across cell
can’t go
membranes that _______
themselves
across by ___________
ACTIVE
Kinds of ________Transport
•________________________________________
Sodium-Potassium Pump
•Endocytosis
___________________________________
____________________________________
•Exocytosis
See a video clip about
Na+-K+ pump -7D
Sodium (Na+)- Potassium (K+)
Pump
Animation from: http://www.lionden.com/cell_animations.htm
See a movie
about Na+ - K+ pump
Sodium-Potassium pump
• ___________
transport
ACTIVE
(requires energy from ______)
ATP
• Special just for Na+ and K
+
ions
Carrier Proteins
• Uses integral ___________________
to move
molecules
• Examples in nerve cells:
Na+ is pumped out of cells at same time
K + is taken into cells
See a video clip about
Endo/exocytosis -7E
ENDOCYTOSIS
Takes substances into cell
ACTIVE
• _____________transport
energy from ______)
ATP
(requires __________
• Uses small membrane sacs called
______________
to carry substances
VESICLES
http://www.sirinet.net/~jgjohnso/cell.html
2 KINDS of ENDOCYTOSIS
Takes substances into cell
If taking in:
PINOCYTOSIS
fluid or small molecules =_________________
PHAGOCYTOSIS
large particles or whole cells =______________
• Examples in cells:
– one celled organisms eat this way
– white blood cells get rid of bacteria this way
Pinocytosis
• Called “Cell Drinking”
ENDOCYTOSIS
Animation from: http://academic.brooklyn.cuny.edu/biology/bio4fv/page/cell-movement.html
http://www.accs.net/users/kriel/chapter%20nine/
PHAGOCYTOSIS
Called “Cell
Eating”
White
blood cell
___________
germs
destroying _______
EXOCYTOSIS
Substances released outside of cell
ACTIVE transport
• __________
energy
(requires __________)
VESICLES
• Substances move in____________
• Examples in cells:
– _________
release packaged proteins
GOLGI
this way
Exocytosis
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBooktransp.html
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
See a Golgi movie
Videos from:
http://www.pleasanton.k12.ca.us/avhsweb/thiel/apbio/notes/chp8/exocytosis_endocytosis.mov
http://trc.ucdavis.edu/biosci10v/bis10v/week2/endocytosis.mov
Endocytosis & Exocytosis
Watch a video clip about endo/exocytosis
Watch a video clip about endo/exocytosis
Choose Screen/Switch programs to view
INSULIN being released by
pancreas cells using exocytosis
http://fig.cox.miami.edu/~cmallery/255/255ion/fig14x26.jpg
http://www.stchs.org/science/courses/sbioa/metenergy/aplantturgor.gif
Plant cells
CELL WALL
_____
keeps
Plant cells from bursting
VACUOLES store WATER
http://www.biology4kids.com/files/cell_vacuole.html
OSMOTIC PRESSURE
_____________________________
=
Pressure exerted by water during osmosis
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?