Cell Membrane and Difussion notes

 I didnt do to good on the test for diffusion so hopefully this will boost up my grade. :)
 

• Cholesterol not always bad helps when temperature changes to keep fluids in the body.
• Membrane- keeps things from going in and going out.
• Cell membrane choices what goes in or out. Doesnt matter how big or small it is, the cell membrane doesnt want it in it wont be in.

Functions of membrane proteins
Channel Proteins:
       -Tubular
      -Allow passages of molecules through membrane
Carrier Proteins:
        - Combine with subtance to be transported
        - Assist passage of molecules through membrane
Cell Recognition Proteins:
        - Provides unique chemical ID for cells
        - Help body recognize foreign substances
Receptor Proteins:
        - Past signals
        - Binds with messenger molecule
        - Causes cell to respond to message
Enzymatic Proteins
        - Carry out metabolic

Types of Transports: Active vs. Passive
Plasma membrane is differentially selectively permeable
        - Allows some material to pass
        - Inhibits passages of other materials
Passive Transport:
        - No ATP requirement- think of as energy
        - Molecules follow concentration gradient
Active Transport
        - Requires carrier protein
        - Requires energy in form of ATP

Diffusion

A solution consists of:
         - A solvent (liquid), and
         - A solute (dissolved solid)
Diffusion
         - Net movement of solute molecules down a concentration gradient = moving from high concentration to low concentration (moves all its parts to everywhere making low concentration)

Water surrounds particles to dissolve it. ----- Where ever there is more dissolved proteins water will follow.