Methods of transport

Warm Up to Molecular Movement

Summarize your understanding of the rules of molecular movement in 3-4 sentences.

Include new terms concentration and concentration gradient

Warm Up to Molecular Movement

Summarize your understanding of the rules of molecular movement in 3-4 sentences.

Include new terms concentration and concentration gradient

Warm Up to Molecular Movement

Whats the BIG IDEA -Summarize your understanding of the rules of molecular movement in 3-4 sentences.

How Molecules Naturally MoveMolecules are always in motion Kinetic energy

2. Molecules move randomly colliding as they move

3. Molecules naturally move from areas where theyre more concentrated to where theyre less concentrated along their concentration gradientConcentration a measure of the number of molecules of a substance in a given volume. Amount of Solute/ Solvent

Methods of transport How materials cross the cell membrane

Key Concept: The cell membrane maintains cellular homeostasis by controlling what substances enter and leave the cell.Remember the cell membrane is selectively permeableCELLThere are many methods by which substances move through the cell.

These methods are grouped on whether or not the cell uses ENERGY Two Major Forms of TransportPassive Cell DOES NOT use Energy Molecules move on their own.

Active Cell DOES use EnergyPassive TransportCells DO NOT use energy

Molecules move from area of greater / high concentration to areas of lesser/ low concentration along/down their concentration gradient

Concentration - measure of the number of molecules of a substance (solute) in a given volume (solvent)

Concentration Gradient Difference in the concentration of a substance from one location to another. Methods of Passive TransportDiffusionFacilitated DiffusionOsmosisDiffusionMolecules move from an area where they are more concentrated to where they are less concentrated along/down their concentration gradient. [HI] [LOW]

Predicting Molecule Movement by DiffusionMolecules move from an area where they have [HI] to where that molecule has a [LOW]

Air Diffusers

Insect Pheromones (Sex Scents)

Diffusion of gases between lungs and blood

Facilitated DiffusionMolecules diffuse through the membrane with the help of a channel or carrier protein

OsmosisDiffusion of water molecules through a semipermeable membrane from an area of higher water concentration to one of lower water concentration.

Higher water concentration Lower solute concentration

Lower water concentration Higher solute concentration

Tonicity

Comparison of Solute Concentration between two different solutions

Iso - equal amounts of solute in/out of cell Hyper more solute High-per Hypo - less solute Hypo-lower

Isotonic Compared solution has the same solute and water concentrations

Hypertonic Compared solution has a higher solute (less water)

Hypotonic Compared solution has a lower solute (more water).

When a cell is put in a hypotonic solutionit gets big like a hippo!!

PlasmolysisPlant Cell Walls protect against changes due to Osmosis

Turgor Pressure and PlasmolysisTurgor pressure -The outward pressure of water in a plant cell. Provides support and structure to plant. Effects of Turgor Pressure

Plant Guard Cells and Turgor Pressure

Think about this.Sea water has a higher concentration of solutes than do human body cells.

Why might drinking large amounts of sea water be dangerous for humans?

Think: High solute concentration in a solution means _____water concentration.Active TransportKey Concept - Movement of materials through the cell membrane which requires the cell to use energy from the ATP molecule.

Methods of Active TransportUsed to move molecules that *Have a charge (Ex. Ions and polar molecules) *Too large to pass through membrane on their own.Must be moved from an area of low concentration o an area of high concentration [Low] [Hi]Active Transport requires the cell to use the high energy carrying molecule ATP (adenosine triphosphate) as its source of energy.Methods of Active TransportMembrane Pumps

Endocytosis

ExocytosisCarrier Proteins/ Membrane PumpsA special carrier protein binds to the molecule to be moved. ATP transfers energy to the carrier protein giving it the E needed to move molecules through the membrane Ex. Sodium Potassium Pump

Endocytosis Taking in of materials by engulfing them in a vesicle

Phagocytosis Cell membrane engulfs large particles or whole organisms Ex. WBCs bacteria and Hungry Amoeba -paramecium!

Pinocytosis Cell membrane engulfs liquid droplets

* Receptor mediated endocytosis Cell membrane has a pit coated with special receptors that attract and transport materials into cell

Exocytosis transport substances out of the cell by using vesiclesOutta Here!

Secretory vesicle Contain molecules to be used outside of the cellEx. Goblet cell

Excretory Vesicles Removal of cellular wasteproducts Video of methods of Endocytosis and Exocytosis

Ways Organisms use Exocytosis and Endocytosis to maintain HomeostasisParamecia contractile vacuoles

Contractile Vacuole Closeup

Phagocytosis of Bacteria by a White Blood Cell

Compare/ Contrast Cell Transport Passive Transport Active Transport Along or Against Concentration Gradient Source of Energy for Transport

Exocytosis Phagocytosis Diffusion Endocytosis Osmosis Facilitated Diffusion Pinocytosis, Receptor Mediated EndocytosisCompare/ Contrast Cell Transport 1. Name 2 Major Categories of Transport 2. Put each method under the correct category Exocytosis Phagocytosis Diffusion Endocytosis Osmosis Facilitated Diffusion Pinocytosis Receptor Mediated Endocytosis Membrane Pumps 3. What characteristics are shared by methods in a category *Molecules Move Along or Against the Concentration Gradient*Cell uses ATP energy to move molecules across membrane OR Molecules move across membrane on their own

Passive TransportMolecules move on their own across cell membrane

Movement direction [HIGH] [Low] Active TransportCell must use ATP energy to move molecules across cell membrane

Always used when movement direction is [LOW] [HIGH]Review of Active and Passive TransportPassive Transport Molecules move, No cell E Diffusion Facilitated Diffusion requires Channel proteins Osmosis Active Transport Cell uses E to move materials Carrier Proteins / Membrane Pumps Endocytosis (Pinocytosis, Phagocytosis) ExocytosisName the 2 Major Groups of Cell TransportDiffusion

Facilitated Diffusion

OsmosisCarrier Proteins/ Membrane Pumps

Endocytosis

ExocytosisCompare/ Contrast Cell Transport Passive Transport Active Transport Along or Against Concentration Gradient Source of Energy for Transport

Exocytosis Phagocytosis Diffusion Endocytosis Osmosis Facilitated Diffusion Pinocytosis, Receptor Mediated EndocytosisCompare/ Contrast Cell Transport 1. Name 2 Major Categories of Transport 2. Put each method under the correct category Exocytosis Phagocytosis Diffusion Endocytosis Osmosis Facilitated Diffusion Pinocytosis Receptor Mediated Endocytosis Membrane Pumps 3. What characteristics are shared by methods in a category *Molecules Move Along or Against the Concentration Gradient*Cell uses ATP energy to move molecules across membrane OR Molecules move across membrane on their own

Passive TransportMolecules move on their own across cell membrane

Movement direction [HIGH] [Low] Active TransportCell must use ATP energy to move molecules across cell membrane

Always used when movement direction is [LOW] [HIGH]Review of Active and Passive TransportPassive Transport Molecules move, No cell E Diffusion Facilitated Diffusion requires Channel proteins Osmosis Active Transport Cell uses E to move materials Carrier Proteins / Membrane Pumps Endocytosis (Pinocytosis, Phagocytosis) ExocytosisName the 2 Major Groups of Cell TransportDiffusion

Facilitated Diffusion

OsmosisCarrier Proteins/ Membrane Pumps

Endocytosis

Exocytosis