Types of Transport Passive transport- No energy required Active Transport- Energy required Endo/Exocytosis- Energy required
Passive Transport Diffusion is the movement of particles from high concentrations to low concentrations, or down its concentration gradient. Concentration- The amount of a substance compared to another.
Diffusion Diffusion works down a concentration gradient, meaning the molecules mix until they reach equilibrium. Passive transport requires no work from the cell. Equilibrium Initial
Facilitated diffusion Diffusion with the help of a protein
Osmosis = diffusion of water water travels from an area of higher concentration to an area of lower water concentration Osmosis occurs when there is an unequal concentration of water on either side of the selectively permeable plasma membrane.
Osmoregulation= Control of water balance Tonicity- The amount of solute in a solution (of a cell) Hypertonic solution- Higher solute concentration than within the cell Hyper= above Hypotonic solution- Lower solute concentration Hypo= below Isotonic- Solute concentrations equal in and out of cell
Active Transport- Energy needed Works against a concentration gradient Requires cell energy (ATP) Uses proteins
Endocytosis & Exocytosis transport large molecules Endocytosis- Cell membrane folds inward, trapping molecules and bringing them inside the cell Exocytosis- Vesicle fuses with the cell membrane and expels its contents. Endo= IN Exo= OUT