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Transporting Molecules. CELL MEMBRANE (also called plasma membrane). Cell membranes are made of ________________ & __________________. PHOSPHOLIPIDS PROTEINS. CELL MEMBRANE. Proteins that stick on the surface = _____________ (either inside or outside of cell)
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CELL MEMBRANE(also called plasma membrane) Cell membranes are made of ________________ & __________________ PHOSPHOLIPIDS PROTEINS
CELL MEMBRANE Proteins that stick on the surface = _____________(either inside or outside of cell) Proteins that stick INTO membrane = ________________ (can go part way in or all the way through)
GLYCOPROTEINS Recognize “self” GLYCOPROTEINS are INTEGRAL PROTEINS
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”
DIFFUSION across a space • Happens anytime there is a __________ in concentration in one place compared to another (________________________)
DIFFUSION across a space • Molecules move automatically from an area of _______ concentration to an area of ________ concentration • EX: _____________________ _____________________ Perfume, Koolaid, popcorn, BBQ, Bad smell in room http://leighhouse.typepad.com/blog/images/kool_aid.jpg http://www.swapmeetdave.com/Humor/Farts.htm
Molecules need to move across membranes in cells Image modiified from: http://www.accessexcellence.org/AB/GG/importProt.html
Diffusion can happen across a membrane in a cell …as long as membrane will let molecule through
Gas exchange between lungs and blood happens by DIFFUSION from HIGHER concentration to LOWER concentration Image modified from: http://www.medaille.edu/vmacer/120_graphic_05oxygen.gif
What if cell needs to move large or polar molecules? EX: _______________ _______________
What if cell needs to move a molecule AGAINST the CONCENTRATION GRADIENT? Example : (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 ________________ ions sends nerve signals http://www.steve.gb.com/images/science/neuron.png
2 KINDS of TRANSPORTacross cell membranes • _____________TRANSPORT Does NOT require energy • ___________TRANSPORT Requires energy
Kinds of Passive Transport __________________________________ ___________________________________ ___________________________________ ___________________________________
DIFFUSION across a membrane • 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: ______________ ______________ http://www.lionden.com/cell_animations.htm
OSMOSIS = SPECIAL KIND OF DIFFUSION • MOVES WATER MOLECULES • Across a MEMBRANE • From HIGHER LOWER http://www.Isbu.ac.uk/water/molecule.html
DIFFUSION Can happen with or without a membrane Molecules that do it: All molecules EXCEPT water Goes until equilibriumExample in cells: Oxygen & Carbon dioxide OSMOSIS Happens across a membraneMolecules that do it:Water Goes until equilibriumExample in cells:Water DIFFUSION or OSMOSISHIGHER LOWER
What if there is a difference in concentration but solute molecules can’t move across a membrane? WATER will move until concentration reaches equilibrium
Osmosis1 http://www.sidwell.edu/us/science/vlb6/labs/a_osmosis.gif
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: _______________________
Facilitated Diffusion Animation from: http://bio.winona.edu/berg/ANIMTNS/facdifan.gif
Kinds of Passive Transport __________________________________ ___________________________________ ___________________________________ ___________________________________ • Diffusion • Osmosis • Facilitated Diffusion • Ion Channels
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 +
ION CHANNELS Some channels always open Some channels have “gates” that open or close in response to signals • SIGNALS: • stretching of cell membrane • electrical signals • chemicals Animation from: http://www2.uic.edu/~myilma1/ionchannel.gif
Kinds of Active Transport ________________________________________ ___________________________________ ____________________________________
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
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 ______________ 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
ENDOCYTOSIS Animation from: http://academic.brooklyn.cuny.edu/biology/bio4fv/page/cell-movement.html
PHAGOCYTOSIS White blood cell destroying germs
EXOCYTOSISSubstances released outside of cell • __________ transport (requires energy) • Substances move in____________ • Examples in cells: • Golgi release packaged proteins
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