transporting molecules
DESCRIPTION
Transporting Molecules. 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 “where there’s A LOT” to “where there’s NOT”. - PowerPoint PPT PresentationTRANSCRIPT
Transporting Molecules
Diffusion
http://lhs.lps.org/staff/sputnam/Biology/U3Cell/diffusion_1.png
Molecules move
from “where there’s A LOT”
to “where there’s NOT”
Animatioin from: http://www.biologycorner.com/resources/diffusion-animated.gif
DIFFUSION across a space
Happens anytime there is a _____________ in concentration in one place compared to another
(________________________)
DIFFERENCE
= Concentration gradient
DIFFUSION across a space
• Molecules move automatically from an area of _______ concentration to an area of ________ concentration
• EX: _____________________ _____________________
HigherLower
Perfume, Koolaid, popcorn,BBQ, Bad smell in room
http://www.swapmeetdave.com/Humor/Farts.htmhttp://leighhouse.typepad.com/blog/images/kool_aid.jpg
Molecules need to
move across membranes
in cells
Image modiified from: http://www.accessexcellence.org/AB/GG/importProt.html
If there is a difference in concentration on two sides of a membrane…Diffusion can happen ACROSS A MEMBRANE too!
…as long as membrane will let molecule through
SELECTIVELY PERMEABLE
DIFFUSION moves them from HIGHER (lungs) concentration to LOWER concentration (blood)
Image modified from: http://www.medaille.edu/vmacer/120_graphic_05oxygen.gif
EXAMPLE: Oxygen molecules move automaticallyfrom lungs into blood
What if cell needs to move large or polar molecules?
EX:
GlucoseAmino acids
What if cell needs to move a molecule AGAINST the CONCENTRATION GRADIENT?
Example :
Glucose into mitochondria
(LOW HIGH)
Image from: http://www.biologyclass.net/mitochondria.jpg
What if cell needs to move molecules really FAST? (can’t wait for it to diffuse)
Example in cells:
Movement of
Na + & K+
ions sends nerve signals
http://www.steve.gb.com/images/science/neuron.png
WAYS MOLECULES MOVE ACROSS MEMBRANES
• PASSIVE TRANSPORT Does NOT require energy
• ACTIVE TRANSPORTRequires energy
Kidspiration by: Riedell
Kinds of Passive Transport
• Diffusion
•Osmosis•Facilitated Diffusion•Ion Channels
__________________________________
___________________________________
___________________________________
___________________________________
DIFFUSION across a membrane• Moves from:
HIGHER concentration LOWER
Any kind of molecule that can pass through the membrane can do this. EX: ______________ ______________
OXYGEN
CARBON DIOXIDE
http://www.lionden.com/cell_animations.htm
OSMOSIS
• MOVES WATER
MOLECULES
• Across a SEMI-PERMEABLE MEMBRANE
• Moves from HIGHER LOWER
http://www.Isbu.ac.uk/water/molecule.html
What if there is a difference in concentration but solute molecules
can’t move across a membrane?
WATER will move until concentrationreaches equilibrium
http://www.sidwell.edu/us/science/vlb6/labs/a_osmosis.gif
Osmosis1
OSMOSIS
HYPERTONIC: Concentration outside cell is ____________________ inside cell
More water leaves cell than enters so cell ____________
GREATER THAN
shrinks
Osmosis4
OSMOSIS
HYPOTONIC: Concentration outside cell is ________________ inside the cell
More water enters than leaves cell so cellwill ___________________
LESS THAN
Swell bigger
Osmosis3
OSMOSIS
ISOTONIC:
Concentration outside cell ____________
concentration inside cell
Water entering = water leavingso cell _____________________
EQUALS
STAYS THE SAME SIZE
Animal cells
= cytolysishttp://www.stchs.org/science/courses/sbioa/metenergy/bloodcells.gif
= crenation
Plant cells
= Plasmolysis
http://www.stchs.org/science/courses/sbioa/metenergy/aplantturgor.gif
No cytolysis/cell wall keeps it from bursting
VACUOLES store WATER
http://www.biology4kids.com/files/cell_vacuole.html
_______________________ =Pressure of water molecules pushing against cell wall
TURGOR PRESSURE
SO WHAT?
SO WHAT?
Sitting in the bathtub causes your fingers and toes to wrinkle up when water enters your skin cells by osmosis
Bath water is HYPOTONICcompared to you
Kinds of Passive Transport
• Diffusion
•Osmosis•Facilitated Diffusion•Ion Channels
__________________________________
___________________________________
___________________________________
___________________________________
Facilitated DiffusionCarrier proteins help diffusion go faster
FACILITATED DIFFUSION• Passive = ____________________
• Moves from ________________________
• _____________________ bind molecule, change shape, and release it on other side of membrane
(Carrier proteins are _______________ proteins)
• Molecules that move this way in cells:_______________________
NO energy required
Carrier Proteins
Integral
GLUCOSE
HIGH LOW
Facilitated Diffusion
Animation from: http://bio.winona.edu/berg/ANIMTNS/facdifan.gif
Kinds of Passive Transport
• Diffusion
•Osmosis•Facilitated Diffusion•Ion Channels
__________________________________
___________________________________
___________________________________
___________________________________
ION CHANNEL
ION CHANNELS• _____________transport (no energy required)
• Molecules move from ___________________
• Small passageways for _______ to get through membrane
• Each ion has own kind of passageway
• Examples in cells: Na+ , Cl- , Ca + + , K +
PASSIVE
HIGH LOW
IONS
ION CHANNELS
Some channels always open
Some channels have “gates”
that open or close
in response to signals
Animation from: http://www2.uic.edu/~myilma1/ionchannel.gif
SIGNALS:•stretching of cell membrane•electrical signals•chemicals
Kidspiration by: Riedell
Kinds of Active Transport
• Sodium-Potassium Pump•Endocytosis
•Exocytosis
________________________________________
___________________________________
____________________________________
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
Na+ and K + PUMP
Animation from: http://www.lionden.com/cell_animations.htm
ENDOCYTOSISTakes substances into cell
• _____________transport (requires energy from ATP)
• Uses small membrane sacs to carry substances
______________
ACTIVE
= VESICLES
http://www.sirinet.net/~jgjohnso/cell.html
2 KINDS of ENDOCYTOSISTakes substances into cell
If taking in:
fluid, 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
ENDOCYTOSISAnimation from: http://academic.brooklyn.cuny.edu/biology/bio4fv/page/cell-movement.html
http://www.accs.net/users/kriel/chapter%20nine/
PHAGOCYTOSIS
White blood cell destroying germs
EXOCYTOSISSubstances released outside of cell
• __________ transport (requires energy)
• Substances move in____________
• Examples in cells:
– Golgi release packaged proteins
ACTIVE
VESICLES
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
Endocytosis & Exocytosis
http://grossmont.gcccd.cc.ca.us/cmilgrim/Bio120/Outline/Outline2.gif/TransportMedia/EndoExocytosisMovie.htm