Crossing the Cell membrane

http://www.biology4kids.com/files/cell_main.html

Diffusion

http://lhs.lps.org/staff/sputnam/Biology/U3Cell/diffusion_1.png

Molecules move _______“where there’s _______” ____“where there’s ___________”

Animatioin from: http://www.biologycorner.com/resources/diffusion-animated.gif

FROMTO

A LOTNOT A LOT

DIFFUSION across a space

Happens anytime there is a __________ in concentration in one place compared to another. This is called the_____________

DIFFERENCE

Concentration gradient

DIFFUSION across a SPACE• Molecules move automatically

_______ the concentration gradient _______ an area of _______ concentration ____ an area of ________ concentration

• EXAMPLES

HigherLesser

Blue dye in beaker demo, Kool Aid,

http://www.swapmeetdave.com/Humor/Farts.htmhttp://leighhouse.typepad.com/blog/images/kool_aid.jpg

DOWNfrom

to

someone making popcorn, grilling out, strong perfume, bad smell in room

DIFFUSION across a space

Diffusion continues until the concentration is _________in space = ___________

Equilibrium

http://lhs.lps.org/staff/sputnam/Biology/U3Cell/diffusion_1.png

ballanced

Kidspiration by: Riedell

Kinds of ________ Transport

•Ion Channel

•Osmosis•Facilitated Diffusion

__________________________________

___________________________________

___________________________________

PASSIVE

Molecules need to move across

membranes in cells

Image modiified from: http://www.accessexcellence.org/AB/GG/importProt.html

Diffusion can happen ________ a _____________ in a cell

…as long as membrane will let the molecule _________________

acrossmembrane

pass through

DIFFUSION across a membrane

Happens anytime there is a __________ in _____________ on one side of the membrane compared to the other

difference

Examples of molecules that move by diffusion across membranes in cells:

OXYGEN, WATER, CARBON DIOXIDE, NITROGEN

http://www.lionden.com/cell_animations.htm

See diffusionanimation

concentration

DIFFUSION automatically moves oxygen from HIGHER concentration (in lungs) to a LOWER concentration (in blood)

http://www.le.ac.uk/pa/teach/va/anatomy/case2/2_2.html

CELL EXAMPLE:

CO2 automatically movesfrom where there is aHIGHER concentration (in blood) to where thereis a lower concentration (in lungs)

SELECTIVELY

PERMEABLE(Semi-

permeable)MOVIE DIFFUSION ACROSS THE

MEMBRANE

http://life.nthu.edu.tw/~d857401/advance.html

OSMOSIS= SPECIAL KIND OF DIFFUSION

IMAGE by RIEDELL

See osmosis animation

____________

__________

OSMOSIS

DIFFUSION

Movement of molecules across a_________________ membranefrom ______ concentration to _____Semi-permeable

Higher lower

BUT….What if a cell needs to move _____ or ______ molecules?

http://www.d.umn.edu/~sdowning/Membranes/membraneImages/jpegimages/diffusionmedium.jpg

LARGE POLAR

Facilitated Diffusion_______ proteins help diffusion go

fasterCarrier

MOVIE DIFFUSION ACROSS

THE MEMBRANE (FACILITATED

DIFFUSION)

What if cell needs to move a molecule _________ the CONCENTRATION GRADIENT?_______________

Cell example:Want to put MORE glucoseinto mitochondria when there

isalready glucose in there

(LOWER HIGHER)

Image from: http://www.biologyclass.net/mitochondria.jpg

AGAINST

What if cell needs to move 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

FAST

We need a ____ to ____ molecules across cell

membranes that _______ across by

___________

WAY HELP

can’t go

themselves

FACILITATED DIFFUSION

• No energy required = __________________

• Moves _________ concentration gradient from ________________________

• _____________________ grab molecule, change shape, and flip to other side (Like a revolving door)

• Molecules that move this way in cells:_______________________

PASSIVE

Membrane proteins

GLUCOSE

HIGHER to LOWERDOWN

Facilitated DiffusionAnimation from: http://bio.winona.edu/berg/ANIMTNS/facdifan.gif

Kidspiration by: Riedell

Kinds of ________Transport

•Sodium-Potassium Pump•Endocytosis•Exocytosis

________________________________________

___________________________________

____________________________________

ACTIVE

See a video clip aboutNa+-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 (requires energy from ______)

• Special just for Na+ and K + ions

• Uses integral ___________________ to move molecules

• Examples in nerve cells: Na+ is pumped out of cells at same time K + is taken into cells

ACTIVE

Carrier Proteins

ATP

See a video clip aboutEndo/exocytosis -7E

ENDOCYTOSISTakes substances into cell

• _____________transport (requires __________ from ______)

• Uses small membrane sacs called ______________ to carry substances

ACTIVE

VESICLES

http://www.sirinet.net/~jgjohnso/cell.html

energy ATP

2 KINDS of ENDOCYTOSIS

Takes substances into cellIf taking in:fluid or small molecules =_________________large particles or whole cells =______________

• Examples in cells:– one celled organisms eat this way– white blood cells get rid of bacteria this

way

PINOCYTOSIS

PHAGOCYTOSIS

PinocytosisPinocytosis

• Called Called “Cell “Cell Drinking”Drinking”

ENDOCYTOSISAnimation from: http://academic.brooklyn.cuny.edu/biology/bio4fv/page/cell-movement.html

http://www.accs.net/users/kriel/chapter%20nine/

PHAGOCYTOSIS

___________ destroying _______White blood cell germs

CalledCalled “Cell “Cell Eating”Eating”

EXOCYTOSISSubstances released outside

of cell

• __________ transport (requires __________)

• Substances move in____________

• Examples in cells:– _________ release packaged proteins

this way

ACTIVE

VESICLES

energy

GOLGI

Exocytosis

http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBooktransp.html

GOLGI BODIES USE EXOCYTOSIS

Animation from: http://www.franklincollege.edu/bioweb/A&Pfiles/week04.html

See a Golgi movie

Video: http://www.southtexascollege.edu/tdehne/BC_ShockwaveAnimations/07SWF-TourOfTheCell/07-16-EndomembraneSystem.swf

Endocytosis & Exocytosis

Watch a video clip about endo/exocytosis

Watch a video clip about endo/exocytosis

Choose Screen/Switch programs to view

Videos from: http://www.pleasanton.k12.ca.us/avhsweb/thiel/apbio/notes/chp8/exocytosis_endocytosis.movhttp://trc.ucdavis.edu/biosci10v/bis10v/week2/endocytosis.mov

INSULIN being released by pancreas cells using

exocytosis

http://fig.cox.miami.edu/~cmallery/255/255ion/fig14x26.jpg

What if there is a difference in concentration but solute

molecules can’t move across a membrane?

WATER will move until concentrationreaches equilibrium

VOCAB_____________ = substance that is

dissolved in a solvent to make a solution

_____________ = substance in which a solute is dissolved

SOLUTE

EX:Koolaid powder = soluteWater = solventKoolaid drink = solution

SOLVENT

http://www.makash.ac.il/h_school/hst/hstsb/chem/luach/dissolve.jpg

__________________ = mass of a solute in a given volume of solution

CONCENTRATION

The _______ molecules there are in a given volume the ____________the concentration

Images by Riedell

MOREGREATER

See a video clip aboutOSMOSIS -7B

 See an animation Osmosis1

http://faculty.etsu.edu/currie/images/osmosis1.jpg

Animation: http://www.ouhscphysio.org/humanphys/animations/osmosis1.swf

OSMOSIS

HYPERTONIC: Concentration outside cell is ____________________ inside cell

More water leaves cell than enters so cell ____________

GREATER THAN

shrinks

See an animationOSMOSIS 4

Animation from: http://www.ouhscphysio.org/humanphys/animations/osmosis4.swf

Cell in Hypertonic SolutionCell in Hypertonic Solution

CELLCELL

15% NaCL85% H2O

5% NaCL95% H2O

What is the direction of water movement?

ENVIRONMENTENVIRONMENT

OSMOSIS

HYPOTONIC: Concentration outside cell is ________________ inside the cell

More water enters than leaves cell so cellwill ___________________

LESS THAN

Swell and possibly burst

See an animationOsmosis3

Animation from: http://www.ouhscphysio.org/humanphys/animations/osmosis3.swf

Cell in Hypotonic SolutionCell in Hypotonic Solution

CELLCELL

10% NaCL90% H2O

20% NaCL

80% H2O

What is the direction of water movement?

OSMOSIS

ISOTONIC: Concentration outside cell

__________concentration inside cell Water entering = water leaving

so cell _____________________

EQUALS

STAYS THE SAME SIZE

Cell in Isotonic SolutionCell in Isotonic Solution

CELLCELL

10% NaCL90% H2O

10% NaCL

90% H2O

What is the direction of water movement?The cell is at _______________.equilibrium

ENVIRONMENTENVIRONMENT

NO NET NO NET MOVEMENMOVEMENTT

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 CellsOsmosis in Red Blood Cells

IsotonicIsotonic Hypotonic

Hypertonic

Plant cellshttp://www.stchs.org/science/courses/sbioa/metenergy/aplantturgor.gif

CELL WALL_____ keepsPlant cells from bursting

VACUOLES store WATER

http://www.biology4kids.com/files/cell_vacuole.html

_____________________________ =Pressure exerted by water during osmosis

OSMOTIC PRESSURE

SO WHAT?

Sitting in the bathtub causes your fingers and toes to wrinkle up when water ________ your skin cells by osmosis

Bath water is ________________compared to youhypotonic

enters

Grocery stores spray water on their veggies to “plump them up”

http://www.painetworks.com/photos/gt/gt0461.JPG

SO WHAT?