Cell Membrane Job = Selectively permeable Three types of molecules: Phospholipids Bi-layer Cell Membrane Non-polar tails inside away from water (Hydrophobic) Polar heads outside (Hydrophilic) Three types of molecules: 1. Phospholipid bilayer 2. Membrane Proteins a. Fibrous b. Transport (pore or channel) c. Peripheral (glycoprotein or enzyme) 3. Cholesterol

Active Transport: Passive Transport: Energy requirements? Driven by? Maintains? Three types: 1. Carrier Proteins 2. Endocytosis a. Pinocytosis (drink) b. Phagocytosis (devour) 3. Exocytosis Passive Transport: Energy requirements? Driven by? Maintains? Three types: 1. Diffusion 2. Osmosis 3. Facilitated Diffusion

Passive Transport: Concentration Gradient … extracellular Diffusion: movement of particles: intracellular

Osmosis = movement of water Concentration of solute in solution outside cell higher, lower, or same then inside cell? Type of solution outside cell: ______________ meaning __________ Movement of water: Explain: Does volume of cell change? 70% Water 30% Salt Cell H2O B. 80% Water 20% Salt 50% Water 50% Salt Cell Concentration of solute in solution outside cell higher, lower, or same then inside cell? Type of solution outside cell: ______________ meaning __________ Movement of water: Explain: Does volume of cell change? H2O C. Concentration of solute in solution outside cell higher, lower, or same then inside cell? Type of solution outside cell: ______________ meaning __________ Movement of water: Explain: Does volume of cell change? 50% Water 50% Salt 90% Water 10% Salt Cell H2O

Osmosis of a Plant Cell Turgor Pressure: water pressure in the plant cell that causes the cell membrane to press against the cell wall. It occurs in a hypotonic solution. Plasmolysis – loss of water from a plant cell, causing pressure to drop in the cell and the cell membrane will shrink. It happens in a hypertonic solution.

Osmosis and Diffusion Diffusion: http://www.dnatube.com/video/30098/The-Process-of-Diffusion-Osmosis Egg Osmosis: shows what happens in hyper/hypo solutions: https://www.youtube.com/watch?v=SSS3EtKAzYc

A B Active or Passive Transport??? 1. Which way would the particles flow if it was passive transport? 2. Which way would the particles be pumped if it was active transport? What would the result be if passive transport is used? What would the result be if active transport is used?

Movement of cells Cilia Flagella

Amoeba with Pseudopod