cell boundaries chapter 7-3. cell membrane regulates what enters and leaves the cell
TRANSCRIPT
Cell BoundariesChapter 7-3
Cell Membrane
Regulates what enters and leaves the cell
Diffusion • Movement of molecules from high to
low concentrations
Osmosis Movement of H2O from area of HIGH
concentration to LOW across a selectively permeable membrane
Hypotonic(“below strength”)
• Water will move INTO the cell causing it to swell
• Cells could rupture if cell takes too much water in
• Increases turgor pressure
“Hypo Hippo”
Hypertonic Solution“above strength”
• Dissolved substances are HIGHER OUTSIDE & LOWER INSIDE the cell
• H2O rushes out of the cell causing it to shrivel
Isotonic Solution“same strength”
Dissolved substances are the SAME OUTSIDE and are the SAME INSIDE
• Movement inside the cell = movement outside
PRACTICE TIME
Facilitated Diffusion• Molecules like glucose can’t just
“diffuse”, they need help by a protein channel.
• DOES NOT REQUIRE ENERGY
• HIGH to LOW
Facilitated Diffusion• High to Low
Active Transport• Requires ENERGY!!! (ATP) adenosine tri-
phosphate and protein pumps• Low concentration to High concentration
Active Transport
Active Transport
“Going Against the Gradient”
Phagocytosis“Cell Eating”
Pinocytosis“cell drinking”
Exocytosis
http://www.youtube.com/watch?v=-6cNX-DpVJw