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WAYS MOLECULES MOVE Chapter 7-3
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Diffusion
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FROM A LOT to NOT Molecules move _______“where there’s _______”
Animatioin from: Molecules move _______“where there’s _______” ____“where there’s _______” FROM A LOT to NOT
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DIFFUSION across a space
Happens anytime there is a __________ in concentration in one place compared to another = ________________________ DIFFERENCE Concentration gradient
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DIFFUSION across a SPACE
Molecules move automatically _______ the concentration gradient _______ an area of _______ concentration ____ an area of ________ concentration EXAMPLES DOWN from Higher to Lower Blue dye in beaker demo, Someone making popcorn/grilling out Strong perfume, Bad smell in room
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DIFFUSION across a space
Diffusion continues until the concentration is ________________ in space = ________________________ equal everywhere Equilibrium
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Molecules need to move across membranes in cells
Image modiified from:
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Diffusion can happen ________ a _____________ in a cell, too
across membrane …as long as membrane will let the molecule _________________ pass through
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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)
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PROBLEM for CELLS? Diffusion only moves molecules from high concentration to low concentration.
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What if cell needs to move a molecule _________ the CONCENTRATION GRADIENT? _______________
AGAINST (LOWER HIGHER) Cell example: Want to put MORE glucose into mitochondria when there is already glucose in there Image from:
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PROBLEM for Cells? Cell membranes are SELECTIVELY PERMEABLE
Video from: PROBLEM for Cells? Cell membranes are SELECTIVELY PERMEABLE
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What if a cell needs to move _____ or ______ molecules that can’t get through the membrane?
LARGE POLAR
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PROBLEM for CELLS? Diffusion happens very slowly
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What if cell needs to move molecules really _______
What if cell needs to move molecules really _______? (can’t wait for it to diffuse) FAST Cell example: Movement of Na + & K+ ions required to send nerve signals
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Cells need a ____ to ____ molecules across cell membranes that _______ across by ___________
WAY HELP can’t go themselves
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Kidspiration by: Riedell
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Kinds of ________ Transport
PASSIVE __________________________________ ___________________________________ _______________________________ Diffusion Facilitated Diffusion Carriers Channels
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DIFFUSION across a membrane
DIFFERENCE Happens anytime there is a __________ in _____________ on one side of the membrane compared to the other concentration See diffusion animation
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DIFFUSION PASSIVE DOWN HIGHER to LOWER OXYGEN Carbon dioxide
DIFFUSION PASSIVE No energy required = _______ Moves _______ concentration gradient from ___________________ Works for any molecules that can pass through the membrane Example of molecules that move this way in cells: ________ & ____________ DOWN HIGHER to LOWER OXYGEN Carbon dioxide
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FACILITATED DIFFUSION uses _______________ to help molecules across 2 kinds of proteins help: _________ & ____________ membrane proteins Carriers Channels Animations from:
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Facilitated Diffusion with CARRIER PROTEINS
Animation from: Carrier protein grabs molecule, changes shape, and flips across to other side like a revolving door
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FACILITATED DIFFUSION with CHANNELS
Membrane proteins create a tunnel through which molecules can pass ION CHANNELS charged _______________ allow________ ions to get past the ____________ center hydrophobic
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FACILITATED DIFFUSION with CHANNELS
polar ________ proteins allow ________ _________ molecules to get past the __________ middle of cell membrane. Aquaporin WATER hydrophobic
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FACILITATED DIFFUSION with CHANNELS
The movement of water molecules across a cell membrane is called ______________ OSMOSIS
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ALL KINDS OF FACILITATED DIFFUSION
PASSIVE No energy required = _____________ Moves ________ concentration gradient from ________________________ ___________________ help molecules get across membrane DOWN HIGHER to LOWER Membrane proteins
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EXAMPLES OF FACILITATED DIFFUSION IN CELLS
CARRIER PROTEINS ION CHANNELS AQUAPORINS (OSMOSIS) GLUCOSE Na+ , Cl- , Ca++ , K+ WATER
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Kidspiration by: Riedell
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Kinds of ________Transport
ACTIVE ________________________________________ __________________________________ ________________________________ ___________________________________ PUMPS Sodium-Potassium Proton Vesicles Endocytosis Exocytosis
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See a video clip about Na+-K+ pump -7D
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Na+ and K + PUMP See a movie about Na+ - K+ pump
Animation from: See a movie about Na+ - K+ pump
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SODIUM-POTASSIUM PUMP
ACTIVE ___________ transport (requires energy from ______) Can move molecules from _____ concentration to ______ Special just for Na+ and K + ions Uses _______________________ called ____________ to move molecules Example: nerve cells Na+ is pumped out of cells at same time K + is taken into cells ATP low high membrane proteins pumps
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PROTON PUMP H+ Moves Protons across membrane = ___ ions
More on this in Chap 8 & 9
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PROTON PUMP ACTIVE ATP low high Protein pumps ___________ transport
(requires energy from ______) Can move molecules from _____ concentration to ________ Special just for H+ ions Uses integral ________________ to move molecules Examples: Lysosomes need acidic conditions for digestion Photosynthesis/Respiration (more on this to come in Ch 8 & 9) ATP low high Protein pumps
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ACTIVE TRANSPORT with VESICLES
___________ are small membrane sacs that pinch off of cell membranes used by cells for transporting molecules Used for transporting molecules: If entering the cell = ______________ If exiting the cell = _______________ ENDOCYTOSIS EXOCYTOSIS
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2 KINDS of ENDOCYTOSIS for taking substances into cell
If taking in: fluid or small molecules =_________________ large particles or whole cells =______________ PINOCYTOSIS PHAGOCYTOSIS Animation from:
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ENDOCYTOSIS Substances taken into cell
ACTIVE energy __________ transport (requires________) Uses ______________ to carry substances Can move molecules from _____ concentration to ______ Examples in cells: one celled organisms eat this way white blood cells get rid of bacteria this way VESICLES low high
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ENDOCYTOSIS Protist eating another
Animation from: Protist eating another
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PHAGOCYTOSIS White blood cell germs ___________ destroying _______
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WHITE BLOOD CELL ENGULFING BACTERIA (Phagocytosis)
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EXOCYTOSIS Substances released outside of cell
ACTIVE energy __________ transport (requires________) Uses ______________ to carry substances Can move molecules from _____ concentration to ______ Examples in cells: _________ release packaged proteins this way VESICLES low high GOLGI
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GOLGI BODIES USE EXOCYTOSIS
Video: GOLGI BODIES USE EXOCYTOSIS Animation from: See a Golgi movie
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Endocytosis & Exocytosis
Videos from: Endocytosis & Exocytosis Watch a video clip about endo/exocytosis video Choose Screen/Switch programs to view
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INSULIN being released by pancreas cells using exocytosis
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Images by Riedell __________________ = mass of a solute in a given volume of solution CONCENTRATION MORE The _______ molecules there are in a given volume the ____________the concentration GREATER
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What if there is a difference in concentration but solute molecules can’t move across a membrane?
WATER will move until concentration reaches equilibrium
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Animation See an animation Osmosis1
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What will happen to an animal cell placed in different solutions?
Solute concentration Greater outside than inside Lower outside than inside Equal outside and inside HYPERTONIC HYPOTONIC ISOTONIC What will happen to an animal cell placed in different solutions?
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Cells try to “maintain stable internal conditions =
Remember: Cells try to “maintain stable internal conditions = ____________________ HOMEOSTASIS So an animal cell in ISOTONIC conditions stays same size Water entering = water leaving Video Choose Blood Isotonic link
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If cells can’t maintain “stable internal conditions” . . .
damage can result and cells can die.
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OSMOSIS swell and possibly burst Video LESS THAN
Animation from: OSMOSIS See an animation Osmosis3 Video Choose Blood Hypotonic link HYPOTONIC: Concentration outside cell is ________________ inside the cell More water enters than leaves cell so cell will ___________________ LESS THAN swell and possibly burst
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OSMOSIS shrinks GREATER THAN Video
Animation from: OSMOSIS See an animation OSMOSIS 4 HYPERTONIC: Concentration outside cell is ____________________ inside cell More water leaves cell than enters so cell ____________ GREATER THAN shrinks Choose Blood Hypertonic link Video
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Animal cells _________ __________ = CYTOLYSIS = CRENATION
_________ __________ = CYTOLYSIS = CRENATION
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Plant cells _____ keeps ___________ = PLASMOLYSIS CELL WALL
Plant cells _____ keeps ___________ plant cells from bursting = PLASMOLYSIS CELL WALL
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VACUOLES store WATER OSMOTIC PRESSURE _____________________________ =
OSMOTIC PRESSURE _____________________________ = Pressure exerted by the movement of water during osmosis
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SO WHAT? hypotonic Bath water is ________________ compared to you
Sitting in the bathtub causes your fingers and toes to wrinkle up when water ________ your skin cells by osmosis enters
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Grocery stores spray water on their veggies to “plump them up”
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SO WHAT?
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