pH Scale A system of classifying how acidic or basic something is. 0-6 8-14 Neutral

How are things able to move in and out of the cell? Cell Transport How are things able to move in and out of the cell?

Cell Membrane Forms a boundary between a cell and the outside environment Controls the passage of materials in and out of cell

Semi-Permeable The cell membrane allows some, but not all, materials to cross *…allows a cell to maintain homeostasis in spite of unpredictable conditions outside of cell Example: Fish net or coffee pot

Cell Transport Can be active or passive

Passive Transport Movement of molecules across a cell membrane without energy input from the cell No additional energy required, but can be slow!

Diffusion Movement of molecules from an area of high concentration to an area of low concentration Example: cookies in the oven

Osmosis The diffusion of water across a semipermeable membrane Regulates a cell’s water content

Summary *Diffusion and osmosis are both methods by which substances can be moved. Diffusion is the movement of particles (salt, sugar, ink, air, etc.). Osmosis is the diffusion of water across a permeable membrane.