Passive and Active Transport Types of Cellular Transport

Passive and Active Transport

Types of Cellular Transport • Animations of Active Transport & Passive Transport • Weee e!!! Passive Transport cell doesn’t use energy 1. Diffusion 2. Facilitated Diffusion 3. Osmosis • high low Active Transport cell does use energy 1. Protein Pumps 2. Endocytosis 3. Exocytosis This is gonna be hard work!! high low

Biological Exchanges: Diffusion and Osmosis • Diffusion: net movement of molecules from an area of high concentration to an area of low concentration. • Example: Sugar or salt dissolving in water. Think Koolaide, instant coffee or tea, Crystal Lite

• Molecules are always in motion • Difference between gas, liquid and solid

Diffusion • Molecules in solution tend to slowly spread apart over time. This is diffusion.

Diffusion concentrated, high energy molecules [High] [Low] diffuse, low energy molecules

Concentration gradient

Diffusion in the Body • Occurs across cell membranes • The cell membrane is differentially permeable (selective) • Movement of water across the membrane is called osmosis

Movement of Molecules Across the Cell Membrane • Oxygen and CO 2 • Water (Osmosis) • Ions (Electrolytes) • Sugar

Osmosis • Osmosis is the movement of WATER across a semi-permeable membrane • At first the concentration of solute is very high on the left. • But over time, the water moves across the semi-permeable membrane, and dilutes the particles. • Video

Animal Cells and Osmosis

Plant Cells and Osmosis Vacuole fills

This requires math… OSMOSIS PRACTICE

Facilitated Diffusion • Molecules that are too large need a specific channel to pass through the membrane • High to low

Passive Transport • No energy • High to low • Ends in equilibrium

Active Transport • Using ATP • Moving against the concentration gradient (moving uphill) • Low to high

Types of Active Transport 1. Protein Pumps transport proteins that require energy to do work • Example: Sodium / Potassium Pumps are important in nerve responses. Sodium Potassium Pumps (Active Transport using proteins) Protein changes shape to move molecules: this requires energy!

Types of Active Transport • 2. Endocytosis: taking bulky material into a cell • Uses energy • Cell membrane in-folds around food particle • “cell eating” • 3. Exocytosis expelling bulky material out of a cell – “spitting out” – Vesicle fuses with membrane, contents exit

Act It Out • Your group of 4 will find a way to act out one of these types of active transport. • Make sure you are showing the main components of the transport that you choose. • Record your skit and email it to me