Passive & Active Transport

Types of Cellular Transport Animations of Active Transport & Passive Transport high low Weeee!!! Passive Transport cell doesn’t use energy Diffusion Facilitated Diffusion Osmosis Active Transport cell does use energy Protein Pumps Endocytosis Exocytosis high low This is gonna be hard work!!

Passive Transport (HighLow) cell uses no energy (ATP) Molecules spread out from an area of high concentration to an area of low concentration. molecules move randomly (HighLow) high low Weeee!!!

3 Types of Passive Transport Diffusion- movement of molecules from HIGH to LOW Facilitative Diffusion – diffusion with the help of transport proteins Osmosis – diffusion of water

Passive Transport: 1. Diffusion Simple Diffusion Animation Passive Transport: 1. Diffusion Diffusion: movement of particles from an area of high concentration to an area of low concentration. (High to Low) molecules continue to move until they are evenly spaced (equilibrium is reached) -molecules will still move around but stay spread out. http://bio.winona.edu/berg/Free.htm

Facilitated diffusion (Channel Protein) Diffusion (Lipid Bilayer) Passive Transport: 2. Facilitated Diffusion A B 2. Facilitated diffusion: diffusion of specific particles through transport proteins found in the membrane Transports larger or charged molecules ( ex; Glucose) Facilitated diffusion (Channel Protein) Diffusion (Lipid Bilayer) Carrier Protein http://bio.winona.edu/berg/Free.htm

Passive Transport: 2. Facilitated Diffusion Glucose molecules Cellular Transport From a- High High Concentration Channel Proteins animations Cell Membrane Low Concentration Protein channel Low Transport Protein Through a  Go to Section:

Passive Transport: 3. Osmosis Osmosis animation 3.Osmosis: diffusion of water through a selectively permeable membrane Water moves from high to low concentrations Water moves freely through pores. Solute (green) to large to move across.

3 osmotic solutions that will affect how water moves 3 solutions affect how water moves 1. Hypertonic solution 2. Hypotonic solution 3. Isotonic solution

Solution is made up of two parts… 1. Universal Solvent = Water Solution is made up of two parts… 1. Solute – substance that is dissolved 2. Solvent – Does the dissolving Example: Ice Tea – water is the solvent and tea and sugar are the solutes + =

1. Hypotonic Solution Hypotonic: The solution has a lower concentration of solutes (sugar, salt,…) and a higher concentration of water than inside the cell. (Low solute; High water) Water will move into Cell The cell will swell or burst. Bursting is called cytolysis (animal) Trick: Hippos love water

2. Hypertonic Solution Hypertonic: The solution has a higher concentration of solutes and a lower concentration of water than inside the cell. (High solute; Low water) Water will move out of Cell The cell will shrivel or shrink. Cells shrinking is called plasmolysis (plant) Trick: Hyper like a viper

3. Isotonic Solution Isotonic: The concentration of solutes in the solution is equal to the concentration of solutes inside the cell. (equal solute, equal water) Water will move in & out of the cell at equal rates The cell will not change size Cell is at equilibrium, homeostasis, dynamic equilibrium

Practice

How Organisms Deal with Osmotic Pressure Paramecium (protist) removing excess water video Bacteria and plants have cell walls that prevent them from over-expanding. In plants the pressure exerted on the cell wall is called tugor pressure. A protist like paramecium has contractile vacuoles that collect water flowing in and pump it out to prevent them from over-expanding. Salt water fish pump salt out of their specialized gills so they do not dehydrate. Animal cells are bathed in blood. Kidneys keep the blood isotonic by remove excess salt and water.

Osmosis practice

Osmosis practice

Osmosis practice

Passive transport overview Characteristics: No Energy required (ATP) High to Low concentrations Molecules move down a concentration gradient 3 examples 1. Diffusion 2. Facilitated diffusion 3. Osmosis 3 solutions – Hypertonic, Hypotonic & Isotonic

This is gonna be hard work!! Active Transport cell uses energy actively moves molecules to where they are needed Movement from an area of low concentration to an area of high concentration (Low  High) high low This is gonna be hard work!!

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

Endocytosis What is happening?

Types of Active Transport 2. Endocytosis: Bulky material entering a cell Endo= into Cytosis = cell Two types: Phagocytosis & Pinocytosis This is how white blood cells eat bacteria!

Two types of Endocytosis 1. Phagocytosis: “cell eating” Trick: “Phago my eggo” Undissolved particles 2. Pinocytosis: “cell drinking” Trick: “virgin pina colada” Dissolved particles

Types of Active Transport 3. Exocytosis: material leaving the cell in bulk Exo = exiting Cytosis = cell “exiting cell” Cell changes shape – requires energy EX: Hormones or wastes released from cell Endocytosis & Exocytosis animations

Practice

Practice In order to make hydrochloric acid, which is required in human digestion, ATP is used to move hydrogen ions from the blood to the stomach lining. This is an example of ___.   Active Transport Passive Transport Osmotic Potential Facilitated Diffusion

Practice