Do Now: (take out homework) Advertisements for sports drinks, such as Gatorade, seem to be everywhere. All of these drinks are supposed to help your body recover and replenish lost electrolytes, fluids, and vitamins after exercise. How do the essential molecules contained in the drinks get into your cells quickly to help you recover after exercise? Do YOU think they really work? Why or why not?

Cell Transport

Getting into a cell Review: What cell organelle controls which materials may enter or leave the cell?

CELL MEMBRANE

Cell (plasma) membrane Cells need an inside & an outside… separate cell from its environment cell membrane is the boundary IN food - sugars - proteins - fats salts O 2 H 2 O OUT waste - ammonia - salts - CO 2 - H 2 O products - proteins cell needs materials in & products or waste out

What IS a membrane? Review: Which organic compound makes up ALL cell membranes?? What do you know doesn’t mix with water?

LIPIDS! (Phospholipids specifically)

Building a membrane How do you build a barrier that keeps the watery contents of the cell separate from the watery environment? What substance do you know that doesn’t mix with water?  FATS   LIPIDS  Remember: oil & water don’t mix!!

Lipids of cell membrane Membrane is made of special kind of lipid phospholipids “split personality” Membrane is a double layer phospholipid bilayer inside cell outside cell lipid “repelled by water” “attracted to water” phosphate

Crossing the cell membrane What molecules can get through the cell membrane directly? fats and oils can pass directly through inside cell outside cell lipid salt aa H2OH2O sugar waste but… what about other stuff?

Two Ways of Transportation PASSIVEACTIVE Does not require ATP Examples: Diffusion Osmosis Facilitated diffusion Requires the use of ATP Examples: Endocytosis Exocytosis Phagocytosis Pinocytosis

POGIL Membrane structure and function Complete model 1 – simple diffusion Model 2 – The selectively permeable membrane 7, 8,

POGIL Review Important vocabulary: Diffusion Concentration Concentration gradient Dynamic Equilibrium Summary: nsport/Egg diffusion

Good Afternoon Good Afternoon Do Now: Copy down homework Castle Learning due THURSDAY UNIT EXAM FRIDAY After school review Jeopardy: 3:00pm Thursday room Come for extra credit points! Correctly answer the following questions QUIETLY and turn in to bin. What are the three components that make up a plasma membrane? Molecules naturally spread from areas of high concentration to an area of low concentration. This is called _____________ and is a form of passive/active transportation.

EGG LAB

Do Now: Take out egg lab Get together in your lab group READ DAY 2 PROCEDURES TOGETHER DO NOT PROCEED!!!

Egg Lab Important concepts Passive Transport! Diffusion – movement of substances Osmosis – movement of water Hypertonic (to shrink) Hypotonic (to swell)

Egg Lab Flow Chart Retrieve one egg Run warm water over the outside of the egg and GENTLY rub away remaining egg shell Measure the initial mass and circumference of the egg Label a cup with your group name and solution Fully submerge the egg in the given solution Let stand for one day The next day record the final mass and circumference Gather class data Interpret observations, draw conclusions

Do Now: Pick up a copy of the notes by the front door How are diffusion and osmosis similar?

Conclusions

OSMOSIS THE DIFFUSION OF WATER!

Keeping water balance Cell survival depends on balancing water uptake & water loss freshwaterbalancedsaltwater

Keeping right amount of water in cell Freshwater a cell in fresh water high concentration of water around cell cell gains water example: Paramecium problem: cells gain water, swell & can burst water continually enters Paramecium cell solution: contractile vacuole pumps water out of cell freshwater No problem, here KABOOM! 1

Keeping right amount of water in cell Saltwater a cell in salt water low concentration of water around cell cell loses water example: shellfish problem: cell loses water in plants: plasmolysis in animals: shrinking cell solution: take up water saltwater I will survive! I’m shrinking, I’m shrinking! 2

Keeping right amount of water in cell Balanced conditions no difference in concentration of water between cell & environment cell in equilibrium example: blood problem: none water flows across membrane equally, in both directions volume of cell doesn’t change balanced I could be better… That’s better! 3

Controlling water Contractile vacuole in Paramecium

What happens when an organism is placed in a 10% salt solution … draw the osmotic situation ….

Osmosis Practice Pogil – Transport in cells model 2 SKIP NUMBERS 16 B, C 17 B, C 20, 22 TURN IN WHEN FINISHED OR COMPLETE FOR HOMEWORK!

Do Now: Draw the diagram on a sheet of loose leaf. Then identify the following: Area of high concentration Area of low concentration Which way is water moving? What is the term used to describe this scenario? (hypertonic, isotonic, or hypotonic) What will physically happen to the cell? Inside: 90% Water 5% Salt Outside: 95% Water, 5% Salt

Good Morning Do Now: Pick up notes and review packet from door. Take out POGIL from yesterday. WRITE: Is it possible to die from drinking too much water? Why or why not?

Passive Transport Facilitated Diffusion

What does it mean “to facilitate”?

FacilitatedDiffusion Facilitated Diffusion A form of passive transport Requires NO energy! Items move from high concentration to low concentration but are too big to move between the phospholipids or through membrane pores These molecules need the assistance of protein channels

Passive Transport Which is which? Diffusion Facilitated diffusion Osmosis A. Diffusion of water from high concentration to low concentration B. Movement of substances from high concentration to low concentration C. Movement of molecules through a membrane through the assistance of a carrier protein. Molecules move from high concentration to low concentration.

What do all forms of passive transport have in common?

NO ENERGY IS REQUIRED. Move from high concentration to low!

rt/ rt/ t/ t/

Pogil Facilitated Diffusion Model 3 Skip number 24 Active transport Model 4 Skip numbers 35-38

How do LARGE molecules enter a cell?

Molecules that are too large can not fit through the membrane proteins. es%20that%20are%20too%20big.gif

Actively using energy! ACTIVE TRANSPORT

Active Transport You wouldn’t stop absorbing oxygen molecules just because there are already SOME in the cell! Active transport requires the use of energy Moves molecules from an area of LOW concentration to an area of HIGH concentration It’s uphill! It needs energy!

HIGH LOW

Example of active transport

Active Transport Energy is also required to bring large molecules inside of the cell and to excrete wastes Endocytosis – Exocytosis –

Endocytosis Bringing stuff in (ENTER!) Pinocytosis Membrane pinches in pulling molecule into a newly formed vacuole Pino = PINCH! Phagocytosis Membrane extends out and wraps around molecule creating a new vacuole

Endocytosis Bringing stuff in (ENTER!) Pinocytosis Membrane pinches in pulling molecule into a newly formed vacuole Pino = PINCH! Phagocytosis Membrane extends out and wraps around molecule creating a new vacuole

Phagocytosis

Pogil Summary: t/ t/

Transport Summary simple diffusion facilitated diffusion active transport ATP