Day 13, Molecule Movement and Cells

Slide 1, Passive Transport

Slide 3, Diffusion

Slide 6, Facilitated Diffusion

Slide 8, Active Transport

Slide 2, Types of Passive Transport

Slide 4, Osmosis

Slide 5, Solution Differences & Cells

Slide 7, Process of Facilitated Transport

-No energy required


-Move due to gradient
differences in concentration, pressure, charge


-Move to equalize gradient
High moves toward low


  1. Diffusion


  2. Osmosis


  3. Facilitated diffusion

-Molecules move to equalize concentration

-Special form of diffusion
-Fluid flows from lower solute concentration to higher solute
-Often involves movement of water
Into cell
Out of cell

Solvent (ex: water) + solute (ex: salt) = solution
Hypotonic
Solutes in cell more than outside
Outside solvent will flow into cell
Isotonic
Solutes equal inside & out of cell
Hypertonic
Solutes greater outside cell
Fluid will flow out of cell

-Channel Proteins help things enter or leave the cell
-Channels usually are transport proteins
(aquaporins facilitate the movement of water)
-No energy is used

-Protein binds with molecule
-Shape of protein changes
-Molecule moves across membrane

-Molecular movement
-Requires energy (against gradient)
-Example is sodium-potassium pump

Slide 9, Endocytosis

Movement of large material
-Particles
-Organisms
-Large molecules
Movement is into cells
Types of endocytosis
bulk-phase (nonspecific)
Protein receptor-mediated (specific)

Slide 10, Process of Endocytosis

-Plasma membrane surrounds material
-Edges of membrane meet
Membranes fuse to form vesicle

Slide 11, Exocytosis

-Reverse of endocytosis
-Cell discharges material

Slide 12, Process of Exocytosis

1.Vesicle moves to cell surface
2.Membrane of vesicle fuses to plasma membrane
3.Materials expelled