1. Bio I Rupp

2.  Why do cells transport materials?  What are the two main methods of cell transport and how do they differ?  What are homeostasis and equilibrium?  What do the terms isotonic, hypertonic, and hypotonic mean? Be able to sketch the scenarios.

3. PASSIVE TRANSPORT  No energy needed  Particles move from high concentration to low concentration ACTIVE TRANSPORT  Energy needed  Particles move from low concentration to high concentration

4.  Diffusion  Osmosis  Facilitated diffusion  Diffusion through ion channels

6. Wastes Out Nutrients In

7.  Diffusion animation Diffusion animation  Simplest type of passive transport  High to low movement  Difference in concentration across a space is the concentration gradient  Example: sugar cube in a beaker  Water molecules are in constant motion and cause the diffusion

8.  Particles want to reach a state of equilibrium  Homeostasis—stable internal conditions of living things

9.  Diffusion of water from a high concentration to a low concentration  Only WATER!!!!  Osmosis animation Osmosis animation

10.  Isotonic—the concentrations of solute inside and outside a cell are equal  Hypertonic—the concentration of solute molecules is higher outside the cell  Hypotonic—the concentration of solute molecules is lower outside the cell

12.  Root cells of plants are surrounded by water—a hypotonic environment  Water moves into the plant  The plant cells swell and push against the cell walls  The pressure on the cell wall is turgor pressure  Turgor pressure stops plants from wilting

14. PLASMOLYSIS  Due to hypertonic environment  Water leaves the cell  Cell shrivels CYTOLYSIS  Due to hypotonic environment  Water enters the cell  Cell swells

16.  Diffusion of large molecules across a cell membrane  Large molecules are helped across by channel proteins  Still passive, therefore; high concentration to low concentration  Facilitated diffusion animation Facilitated diffusion animation

17.  Charged particles, ions, are moved from high concentration to low concentration  Why can’t ions diffuse directly through the membrane?—think about the cell membrane phospholipid bilayer!!

18.  Sodium-Potassium pumps  Endocytosis  Pinocytosis  Phagocytosis  Exocytosis

19.  Many cells need higher concentrations of sodium outside the cell and higher concentrations of potassium inside the cell  From low concentration to high concentration  Energy needed in the form of ATP  Sodium-potassium pump animation Sodium-potassium pump animation

20.  Endo means in and cyto refers to a cell, therefore; this is cells ingesting materials  Pinocytosis—ingestion of fluids—cell drinking  Phagosytosis—ingestion of solid molecules—cell eating—phagocytes and lysosomes  Endocytosis animation Endocytosis animation

21.  Reverse of endocytosis  Waste removal process