AIM:AIM: How is the structure of the plasma How is the structure of the plasma membrane related to its function?membrane related to its function?

DO NOW:DO NOW: What are some other names for What are some other names for the cell membrane?the cell membrane?

What does the cell What does the cell membrane do?membrane do?

FunctionsFunctions

Helps to maintain balance or homeostasis Helps to maintain balance or homeostasis within the cellwithin the cell

Boundary between cell and its Boundary between cell and its environmentenvironment

Selectively permeable: allows some to Selectively permeable: allows some to pass and others are kept outpass and others are kept out

How is the cell membrane How is the cell membrane constructed?constructed?

The cell membraneThe cell membrane

Plasma membranePlasma membrane

Phospholipid bilayerPhospholipid bilayer

2 layers of 2 layers of phospholipidsphospholipids– Embedded with Embedded with

proteins and proteins and cholesterol moleculecholesterol molecule

Construction of the Cell MembraConstruction of the Cell Membranene

Wisconsin Online Wisconsin Online

WednesdayWednesday

AIM:AIM: How is the cell membrane selectively How is the cell membrane selectively permeable?permeable?

DO NOW:DO NOW: Explain the difference between Explain the difference between hydrophilic heads and hydrophobic tails.hydrophilic heads and hydrophobic tails.

Homework:Homework: Textbook read pages 201- Textbook read pages 201-202. Review figure 7.20 and explain what 202. Review figure 7.20 and explain what is happening. Define dynamic equilibriumis happening. Define dynamic equilibrium

Structure of a phospholipidStructure of a phospholipid

Hydrophilic heads:Hydrophilic heads: water lovingwater loving– Made up of phosphate Made up of phosphate

and glyceroland glycerol

Hydrophobic tails:Hydrophobic tails: do not like waterdo not like water– Built from long Built from long

hydrocarbon fatty acid hydrocarbon fatty acid tailtail

Why is it important for the Why is it important for the membrane to be partly membrane to be partly hydrophobic and partly hydrophobic and partly

hydrophilic?hydrophilic?

http://http://www.susanahalpine.com/aniwww.susanahalpine.com/anim/Life/memb.htmm/Life/memb.htm

How do membrane proteins and How do membrane proteins and cholesterol create a fluid cholesterol create a fluid

mosaic?mosaic?

Cell Membrane - VideoCell Membrane - Video

Membrane proteinsMembrane proteins

Peripheral:Peripheral: at the surface of cell at the surface of cell membranemembrane– Fibrous proteins:Fibrous proteins: receptors receptors– Glycoproteins:Glycoproteins: cell to cell recognition or cell to cell recognition or

identificationidentification

Integral:Integral: occupy the length of the bilayer occupy the length of the bilayer– Pore proteins:Pore proteins: passive transport passive transport– Channel proteins:Channel proteins: active transport active transport– Ion pumpsIon pumps

Why does the membrane need Why does the membrane need cholesterol?cholesterol?

Helps stabilize the membraneHelps stabilize the membrane

Cholesterol is lipid solubleCholesterol is lipid soluble

How does the structure of the How does the structure of the membrane relate to its function?membrane relate to its function?

Friday 12/7/12Friday 12/7/12

AIM: how does the structure of the cell AIM: how does the structure of the cell membrane relate to its function?membrane relate to its function?

DO NOW: What do you think would DO NOW: What do you think would happen to a fresh water fish if you put it in happen to a fresh water fish if you put it in salt water and explain why you think thatsalt water and explain why you think that

HOMEWORK: Text page 183 questions 1-HOMEWORK: Text page 183 questions 1-33

Fluid Mosaic modelFluid Mosaic modelIndividual phospholipids Individual phospholipids are not bondedare not bondedFluid because Fluid because phospholipids move phospholipids move At the same time, At the same time, proteins in the proteins in the membrane also move membrane also move among the among the phospholipidsphospholipidsProteins, cholesterol Proteins, cholesterol and carbohydrates and carbohydrates create a mosaic modelcreate a mosaic model

Explain the difference between Explain the difference between an integral and a peripheral an integral and a peripheral

protein.protein.

Integral proteins are large enough to Integral proteins are large enough to span both layers of the phospholipid span both layers of the phospholipid

bilayerbilayerPeripheral proteins only span one layerPeripheral proteins only span one layer

How does the cell membrane How does the cell membrane maintain homeostasis?maintain homeostasis?

By regulating and helping molecules enter or By regulating and helping molecules enter or leave the cellleave the cell

Membrane proteins and hydrophillic heads Membrane proteins and hydrophillic heads help molecules enter and/or leave the cellhelp molecules enter and/or leave the cell

Tuesday 12/11/12Tuesday 12/11/12

AIM:AIM: How does the cell membrane How does the cell membrane maintain homeostasis?maintain homeostasis?DO NOW:DO NOW: 1- The cell organelles 1- The cell organelles crossword puzzlecrossword puzzle2- does the cell membrane function the 2- does the cell membrane function the same in the plant and in the animal cell? If same in the plant and in the animal cell? If so what is its function.so what is its function.HOMEWORK:HOMEWORK: textbook page 169 and 170 textbook page 169 and 170 questions 2,4,5,6,8,9,11questions 2,4,5,6,8,9,11

The structure of the cell membrane The structure of the cell membrane helps it regulate homeostasishelps it regulate homeostasis

HOW?HOW?

By being selectively permeableBy being selectively permeable

This means it chooses certain molecules This means it chooses certain molecules to crossto cross

NOT ALL MOLECULES CAN CROSS NOT ALL MOLECULES CAN CROSS THE CELL MEMBRANETHE CELL MEMBRANE

Use your notes to design a well organized Use your notes to design a well organized table using the parts and the functions that table using the parts and the functions that build the plasma membranebuild the plasma membrane

Thursday 12/13/12Thursday 12/13/12

AIM:AIM:how do molecules move across the how do molecules move across the cell membrane?cell membrane?

DO NOW:DO NOW: Explain why the plasma Explain why the plasma membrane is called a phospholipid bilayer.membrane is called a phospholipid bilayer.

Explain why the plasma membrane is Explain why the plasma membrane is called a fluid mosaiccalled a fluid mosaic

HOMEWORK:HOMEWORK:Text page 191 questions 1-Text page 191 questions 1-55

Membrane proteinsMembrane proteins

IntegralIntegral– Carrier protiensCarrier protiens– Channel proteinsChannel proteins

PeripheralPeripheral– Glycoproteins: part carbohydrate part proteinGlycoproteins: part carbohydrate part protein

What are the functions of the Cell What are the functions of the Cell Membrane?Membrane?

Selective PermeabilitySelective Permeability

Maintain homeostasisMaintain homeostasis

Create a barrierCreate a barrier

Structural supportStructural support

The cell membraneThe cell membrane

Regulates homeostasis by controlling Regulates homeostasis by controlling which molecules can enter and/or leave which molecules can enter and/or leave the cellthe cell

Does the cell membrane let Does the cell membrane let ALL molecules across?ALL molecules across?

How does the cell membrane How does the cell membrane choose which molecules to choose which molecules to

cross?cross?

Factors which effect permeabilityFactors which effect permeability

Size of moleculeSize of molecule

Solubility of moleculeSolubility of molecule– Does it dissolve in waterDoes it dissolve in water– Does it dissolve in lipidDoes it dissolve in lipid

Charge on moleculeCharge on molecule

Concentration gradient: amount or quantity Concentration gradient: amount or quantity of molecules on either side of the of molecules on either side of the membranemembrane

TransportTransport

Passive:Passive: molecules move from a high to molecules move from a high to low concentrationlow concentration

Active:Active: molecules move from low to high molecules move from low to high concentrationconcentration

AssessmentAssessment

Explain how concentration gradient is a Explain how concentration gradient is a driving force of transportdriving force of transport

Tuesday 12/18/12 pd 7Tuesday 12/18/12 pd 7

AIM: How do molecules move down the AIM: How do molecules move down the concentration gradient?concentration gradient?

DO NOW: 1- Draw the picture below\DO NOW: 1- Draw the picture below\

2-which direction will molecules move and why?2-which direction will molecules move and why?

HOMEWORK: Reading Comprehension handoutHOMEWORK: Reading Comprehension handout

Essential Biochemistry - MemEssential Biochemistry - Membrane Transportbrane Transport

Slides 1-6Slides 1-6

Transport across the membraneTransport across the membrane

Cytoplasm has different Cytoplasm has different molecules and ions. molecules and ions.

Some easily pass through Some easily pass through the plasma membrane the plasma membrane into the cell. into the cell.

These include water, These include water, oxygen, carbon dioxide, oxygen, carbon dioxide, glucose and sodium and glucose and sodium and chloride ions.chloride ions.

Passive TransportPassive Transport

Small lipid soluble molecules move from a Small lipid soluble molecules move from a crowded area to a less crowded areacrowded area to a less crowded area

Down the concentration gradientDown the concentration gradient

No energy is requiredNo energy is required

Simple DiffusionSimple Diffusion

Facilitated DiffusionFacilitated Diffusion

OsmosisOsmosis

These include water, oxygen, carbon dioxide, These include water, oxygen, carbon dioxide, glucose and sodium and chloride ions.glucose and sodium and chloride ions.

Passive transportPassive transport

How do molecules know when to How do molecules know when to stop moving?stop moving?

Dynamic equilibrium: same amount of Dynamic equilibrium: same amount of molecules on each side of the membranemolecules on each side of the membrane

Essential Biochemistry - MemEssential Biochemistry - Membrane Transportbrane Transport

7-87-8

Simple DiffusionSimple Diffusion

Movement is driven Movement is driven by by concentration concentration gradientgradient

Molecules move from Molecules move from an area of an area of high high concentration to concentration to lowlow concentrationconcentration

Solute concentration Solute concentration is equalis equal

Facilitated diffusionFacilitated diffusion

Some molecules are Some molecules are too big to simply too big to simply diffuse diffuse

So they need the help So they need the help of carrier proteinsof carrier proteins

Transport is still Transport is still driven by a driven by a concentration concentration gradientgradient

AIM:AIM: Why is osmosis simple diffusion? Why is osmosis simple diffusion?

DO NOW:DO NOW: Explain why energy is not Explain why energy is not needed to move glucose down the needed to move glucose down the concentration gradient of the cell.concentration gradient of the cell.

Homework: Reading Comprehension handout Cell transport: Read pages 111- Read pages 111-113. answer questions 1-5 on pages 11-113. answer questions 1-5 on pages 11-113. Questions 1-3 on Pages 115-116.113. Questions 1-3 on Pages 115-116.

Period 2 Tuesday 12/18/12Period 2 Tuesday 12/18/12

AIM: How do water molecules move across the cell How do water molecules move across the cell membrane?membrane?DO NOW:DO NOW: The cell transport handout page 111 Reading The cell transport handout page 111 Reading toolbox: create a concept map connecting the following toolbox: create a concept map connecting the following terms: terms: the cell membrane, concentration gradient, the cell membrane, concentration gradient, cell transport, the plasma membrane, passive cell transport, the plasma membrane, passive transport, active transport, down, against, transport, active transport, down, against, molecules, move, high, low, ATP, ion pump, the molecules, move, high, low, ATP, ion pump, the phospholipid bilayer, energy, simple diffusion, phospholipid bilayer, energy, simple diffusion, facilitated diffusion, osmosis, equilibrium, carrier facilitated diffusion, osmosis, equilibrium, carrier proteinsproteinsHOMEWORK: The cell transport handout page 116 questions 4-6

How is simple diffusion similar from How is simple diffusion similar from facilitated diffusion?facilitated diffusion?

Both are examples of Passive transportBoth are examples of Passive transport

So they both move molecules from high to So they both move molecules from high to low concentrationlow concentration

We call that moving down the We call that moving down the concentration gradientconcentration gradient

How is simple diffusion similar from How is simple diffusion similar from facilitated diffusion?facilitated diffusion?

Both are types of passive transportBoth are types of passive transport

So they move molecules down the So they move molecules down the concentration gradientconcentration gradient

Which means molecules move from high Which means molecules move from high concentration (a lot) to low concentration concentration (a lot) to low concentration ( a little)( a little)

How is simple diffusion different How is simple diffusion different from facilitated diffusion?from facilitated diffusion?

Facilitated diffusion uses a membrane Facilitated diffusion uses a membrane carrier proteincarrier protein

WHY?WHY?

Because some molecules are too big to Because some molecules are too big to cross the membrane by itselfcross the membrane by itself

Wednesday 12/19/12Wednesday 12/19/12

AIM:AIM: How does solute concentration How does solute concentration regulate osmosis?regulate osmosis?DO NOW:DO NOW: 1- Take out your handout 1- Take out your handout2- explain the similarities between osmosis 2- explain the similarities between osmosis and simple diffusion.and simple diffusion.HOMEWORK:HOMEWORK: Read page 180. Explain Read page 180. Explain what happens to Red blood cells in what happens to Red blood cells in hypertonic, hypotonic and isotonic hypertonic, hypotonic and isotonic environmentsenvironments

Simple diffusion and osmosisSimple diffusion and osmosis

Both move molecules from high to low Both move molecules from high to low concentrationsconcentrations

DO NOT NEED ENERGYDO NOT NEED ENERGY

Types of passive transportTypes of passive transport

Differences between simple Differences between simple diffusion and osmosisdiffusion and osmosis

Osmosis is the simple diffusion of water Osmosis is the simple diffusion of water molecules ONLYmolecules ONLY

Simple diffusion moves small molecules Simple diffusion moves small molecules like oxygen and ionslike oxygen and ions

The cell membrane is selectively The cell membrane is selectively permeablepermeable

That means it picks and chooses which That means it picks and chooses which molecules can crossmolecules can cross

OsmosisOsmosis

Simple diffusion of Simple diffusion of waterwaterWater molecules Water molecules move from a move from a concentrated area to concentrated area to a less concentrated a less concentrated areaareaSolute; dissolved Solute; dissolved moleculemolecule– Glucose, salt, ionsGlucose, salt, ions

ActivityActivity

On a clean sheet of loose leaf, list and On a clean sheet of loose leaf, list and briefly describe the similarities and briefly describe the similarities and differences of each type of passive differences of each type of passive transport.transport.

Osmosis.mp4 - YouTubeOsmosis.mp4 - YouTube

TonicityTonicity

Refers to the solute concentration on Refers to the solute concentration on either side of the cell membraneeither side of the cell membrane

Measures how many solute molecules are Measures how many solute molecules are dissolved inside of the cell and out side of dissolved inside of the cell and out side of the cellthe cell

Isotonic: equal movement of water Isotonic: equal movement of water into and out of cellinto and out of cell

Hypotonic solution: net water Hypotonic solution: net water movement into the cellmovement into the cell

Hypertonic: net movement of water Hypertonic: net movement of water out of the cellout of the cell

AssessmentAssessment

In your own words, explain why you feel In your own words, explain why you feel dehydrated after eating a large bag of dehydrated after eating a large bag of salty potato chipssalty potato chips

Osmosis in the kitchen - YouTOsmosis in the kitchen - YouTubeube

Osmosis in plant cellsOsmosis in plant cells

PlasmolysisPlasmolysis in Elodea - YouTube in Elodea - YouTube

PlasmolysisPlasmolysis

hypertonic hypertonic environment: cell environment: cell loses waterloses water

Cell membrane Cell membrane separates from cell separates from cell wallwall

Friday 1/4/13Friday 1/4/13

AIM:AIM: How does the cell membrane How does the cell membrane regulate osmosis?regulate osmosis?DO NOW:DO NOW: Why do you feel dehydrated Why do you feel dehydrated after eating a large salty popcorn and after eating a large salty popcorn and drinking a sugary soda?drinking a sugary soda?HOMEWORK:HOMEWORK: Textbook read pages: Textbook read pages:1- DEFINE active transport1- DEFINE active transport2- List and describe the different types of 2- List and describe the different types of active transportactive transport

KScienceKScience - Animations - Animations

Osmosis in plants (Red OnioOsmosis in plants (Red Onion) - YouTuben) - YouTube

Add salt solution (hypertonic)Add salt solution (hypertonic)

If I add fresh water to If I add fresh water to Cell A and let it sit for Cell A and let it sit for an hour what will an hour what will happen?happen?

Complete the drawing Complete the drawing of picture B and of picture B and explain what has explain what has happened.happened.

Hypotonic environmentHypotonic environment

Water rushes into the cell and the cell Water rushes into the cell and the cell swellsswells

Lysis:Lysis: the cell bursts the cell bursts– Cannot stop water from enteringCannot stop water from entering

What happens to single celled organisms What happens to single celled organisms like the ameba?like the ameba?

Contractile vacuoleContractile vacuole

Monday 1/7/13Monday 1/7/13

AIM:AIM: How does the cell use energy to How does the cell use energy to transport molecules across the plasma transport molecules across the plasma membrane?membrane?

DO NOW:DO NOW: Use the picture displayed to Use the picture displayed to explain how the molecules will move:explain how the molecules will move:

How does the concentration How does the concentration gradient determine the gradient determine the direction of molecule direction of molecule

movement across the cell movement across the cell membrane?membrane?

Active transportActive transport

Movement of substances Movement of substances againstagainst a a concentration gradientconcentration gradient

From From low to highlow to high

Needs energyNeeds energy

Membrane proteins use energy to move Membrane proteins use energy to move individual moleculesindividual molecules

How does active transport differ How does active transport differ from facilitated diffusion?from facilitated diffusion?

What happens to a plant cell when I place What happens to a plant cell when I place it in salt water?it in salt water?

How is active transport different How is active transport different from passive transport?from passive transport?

Passive transport does Passive transport does not need energy to move not need energy to move molecules from high to molecules from high to low concentrationlow concentration

Active Transport uses Active Transport uses energy to move energy to move molecules against the molecules against the concentration gradientconcentration gradient

Differences between Active Differences between Active transport and facilitated diffusiontransport and facilitated diffusionActive TransportActive Transport– Uses energyUses energy– Moves molecules from Moves molecules from

low to high low to high concentrationconcentration

– Moves molecules Moves molecules against the against the concentration gradientconcentration gradient

Facilitated diffusionFacilitated diffusion– Does not use energyDoes not use energy– Moves molecules from Moves molecules from

high to low high to low concentrationconcentration

– Moves molecules Moves molecules down the down the concentration gradientconcentration gradient

Why is active transport necessary Why is active transport necessary for homeostasis?for homeostasis?

Certain molecules need to enter or leave Certain molecules need to enter or leave the cell against their concentration the cell against their concentration gradientgradient

Ion TransportIon Transport

CotransportCotransport

movement of 2 movement of 2 solutes togethersolutes together

often moves 1 solute often moves 1 solute passively & other passively & other actively actively

AssessmentAssessment

In your notebooks draw the picture In your notebooks draw the picture depicted below and explain how molecules depicted below and explain how molecules move in the direction of the arrowsmove in the direction of the arrows