Question of the DayQuestion of the Day

1.1. Homeostasis = ???Homeostasis = ???

2.2. What kind of solution can cause a cell What kind of solution can cause a cell to burst (explode)? to burst (explode)? isotonic, isotonic, hypotonic, or hypertonic?hypotonic, or hypertonic?

3.3. Water crosses through a ________ Water crosses through a ________ ____________ __________ during ____________ __________ during osmosis.osmosis.

12-7

ReviewReview

Lab

Pages 6 and 7 questions

12-712-7

Question of the DayQuestion of the DayGet out a clean piece of paper you can turn inGet out a clean piece of paper you can turn in

QuestionsQuestions::

1.1. What is osmosis?What is osmosis?

2.2. What is a hypertonic solution? What What is a hypertonic solution? What happens to the cell in this type of solution?happens to the cell in this type of solution?

3.3. What is a hypotonic solution? What happens What is a hypotonic solution? What happens to the cell in this type of solution?to the cell in this type of solution?

12-8

Control = 56.5 gramsControl = 56.5 grams

Lab

Notes Page 8

12-812-8

Contractile VacuolesContractile Vacuoles – – Organelle that excretes excess water from Organelle that excretes excess water from

cellscellsUses ATPUses ATPUsually found in unicellular freshwater organisms.Usually found in unicellular freshwater organisms.This prevents them from bursting in a hypotonic This prevents them from bursting in a hypotonic

solution.solution.

Contractile vacuoleContractile vacuole

PlasmolysisPlasmolysis – –loss of turgor pressure in plant cell loss of turgor pressure in plant cell

due to loss of waterdue to loss of waterWhat happens to a plant during What happens to a plant during

plasmolysis? plasmolysis? The plant wiltsThe plant wiltsThe plants plasma membrane and cytoplasm The plants plasma membrane and cytoplasm

will shrink away from the cell wallwill shrink away from the cell wall

REVIEW:REVIEW:What will happen to an Elodea Leaf in a What will happen to an Elodea Leaf in a

hypertonic solution?hypertonic solution?Water will leave the cell…Water will leave the cell…

……which is called playsmolsis, which will cause the which is called playsmolsis, which will cause the plant leaves to wiltplant leaves to wilt

ReviewReview If we put Elodea leaves in a hypotonic If we put Elodea leaves in a hypotonic

solution, what happens? solution, what happens? Water will move into the cell….Water will move into the cell….

…….which will cause the cell to swell. If it’s an .which will cause the cell to swell. If it’s an animal cell it will….animal cell it will….

……burst, UNLESS the cell has a burst, UNLESS the cell has a Contractile vacuole to pump the water out. toContractile vacuole to pump the water out. to

Summary of Hypo/Hypertonic solution Summary of Hypo/Hypertonic solution changes on a RBC.changes on a RBC.

ReviewReview If the cell shrinks, it is in what type of solution?If the cell shrinks, it is in what type of solution? If the cell is at equilibrium with it’s If the cell is at equilibrium with it’s

environment, its in what type of solution?environment, its in what type of solution? If the cell swells, it’s in what type of solution?If the cell swells, it’s in what type of solution?

Water –90%

Salt – 10%

Water 95%

Salt 5%

Water 50%

Salt 50%

Water 50%

Salt 50%

Water 64%

Salt 36%

Water 44%

Salt 56%

pages 6-7 assignment

pages 6-7 assignment

Egg Lab ReportEgg Lab Report

GraphGraph Must be coloredMust be colored Graph your starting Graph your starting

mass and then use mass and then use your final mass datayour final mass datawhich is in bluewhich is in blue

Add a column to you data table:Add a column to you data table: ““Percent Change in Mass”Percent Change in Mass”

((Initial Mass – Final Mass) / Initial ((Initial Mass – Final Mass) / Initial Mass) x 100 Mass) x 100

Calculate all the changes in mass for Calculate all the changes in mass for your eggyour egg

Starting Starting Mass Mass (grams)(grams)

Final Final Mass Mass (g)(g)

Change Change in mass in mass (g)(g)

% Change in Mass % Change in Mass

((Initial Mass – Final ((Initial Mass – Final Mass) / Initial Mass) x Mass) / Initial Mass) x

100100 Egg in Egg in shellshell ========== ======== ======

VinegarVinegar

Corn Corn SyrupSyrup

DistilledDistilled

Egg Lab ReportEgg Lab Report

Analysis of your Data:Analysis of your Data: Be sure you are using the terms we’ve discussed in Be sure you are using the terms we’ve discussed in

class in your explanation of your results.class in your explanation of your results. ExampleExample

What you should turn in:What you should turn in: Page 1 – DirectionsPage 1 – Directions Page 2 – Written lab reportPage 2 – Written lab report Page 3 – GraphPage 3 – Graph Page 4 – Your actual lab procedurePage 4 – Your actual lab procedure

Selective PermeabilitySelective Permeability – – plasma membrane to allows some plasma membrane to allows some

materials to pass while keeping others outmaterials to pass while keeping others outWhy is selective permeability important?Why is selective permeability important?

So the cell can allow important substance So the cell can allow important substance in (water, oxygen, glucose) and keep in (water, oxygen, glucose) and keep harmful substances out (bacteria).harmful substances out (bacteria).

Passive TransportPassive Transport Passive TransportPassive Transport – –

movement of particles across membranes by movement of particles across membranes by diffusiondiffusion

This process uses no ATPThis process uses no ATP Molecules moving from hi concentration Molecules moving from hi concentration low low

concentrationconcentration

Facilitated DiffusionFacilitated Diffusion – – nname for passive transport using transport proteins ame for passive transport using transport proteins Does not use energy!!!Does not use energy!!!

Example:Example: Glucose going from high concentration outside cell Glucose going from high concentration outside cell

low concentration inside the celllow concentration inside the cell Why doesn’t this need energy?Why doesn’t this need energy?

Because it’s still along the concentration gradientBecause it’s still along the concentration gradient

Transport / carrier proteins – Transport / carrier proteins – proteins that assist facilitated diffusionproteins that assist facilitated diffusion

Ion channels – Ion channels – proteins transport ions from high concentration to proteins transport ions from high concentration to

lower concentrationlower concentration Ions like Na+, Ca+, etc are not soluble in lipids, Ions like Na+, Ca+, etc are not soluble in lipids,

so they must travel through proteins channelsso they must travel through proteins channels Ion channels are ion specific Ion channels are ion specific

Some channels are always open, some have gateSome channels are always open, some have gate Gates open from stimuli: stretching of cell Gates open from stimuli: stretching of cell

membrane electrical or chemical signalsmembrane electrical or chemical signals

Active TransportActive Transport – – transport of materials against a concentration transport of materials against a concentration

gradient – requires energygradient – requires energy ATPATP (adenosine tri-phosphate) – (adenosine tri-phosphate) –

the ENERGY molecule for the cellthe ENERGY molecule for the cell Breaks down from Breaks down from

ATP ATP ADP (Adenosine ADP (Adenosinedi-phosphate)di-phosphate)

Hydrolysis of the Hydrolysis of the phosphate releasesphosphate releasesenergyenergy

Active TransportActive Transport

Active Transport ExampleActive Transport Examplehttp://www.youtube.com/watch?v=STzOiRqzzL4&feature=relatedhttp://www.youtube.com/watch?v=STzOiRqzzL4&feature=related

Sodium-potassium PumpSodium-potassium Pump – – transfer protein exampletransfer protein example Transfers Na+ out and K+ inTransfers Na+ out and K+ in

Creates electrical gradient which is important for Creates electrical gradient which is important for nerve impulsesnerve impulses

http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_the_sodium_potassihttp://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_the_sodium_potassium_pump_works.htmlum_pump_works.html

Na+ / K+ PumpNa+ / K+ Pump

EndocytosisEndocytosis – – when a cell surrounds and takes in when a cell surrounds and takes in

material from the environmentmaterial from the environmentUses ATPUses ATP

EndocytosisEndocytosis

Pinocytosis – Pinocytosis – Transport of fluids into the cellTransport of fluids into the cell

Phagocytosis – Phagocytosis – Transfer of large particles / cells into the cellTransfer of large particles / cells into the cell

Phagocytes – Phagocytes – Cells that ingest bacteria / viruses and Cells that ingest bacteria / viruses and

lysosomes fuse w/ vesicle to destroy them lysosomes fuse w/ vesicle to destroy them before harm done before harm done

http://www.youtube.com/watch?v=1w10R9lv7eQhttp://www.youtube.com/watch?v=1w10R9lv7eQ

ExocytosisExocytosis – – when a cell expels materials to the when a cell expels materials to the

extracellular environmentextracellular environmentCell exports proteins, hormones and wastes Cell exports proteins, hormones and wastes

this waythis wayThis process uses ___This process uses ___ATPATP______

Endo / ExocytosisEndo / Exocytosis

Exocytosis and endocytosisExocytosis and endocytosishttp://www.youtube.com/watch?v=K7yku3http://www.youtube.com/watch?v=K7yku3

sa4Y8sa4Y8

The EndThe End

Warm Up 1-5Warm Up 1-5Draw and Label Each – hypotonic, Draw and Label Each – hypotonic,

hypertonic, isotonic, active transport, hypertonic, isotonic, active transport, diffusion: (Blue circles = cells)diffusion: (Blue circles = cells)

NaCl 25% NaCl 12%

Sugar 10%

NaCl 35%

Sugar 5%

NaCl 20%

ATP used

Dialysis Tubing LabDialysis Tubing LabGroups of two or three (NOT 4)Groups of two or three (NOT 4)Read through part 1 – create a flow chart Read through part 1 – create a flow chart

of the procedureof the procedure

Warm Up 1-6Warm Up 1-6

How is the dialysis tubing “selective”?How is the dialysis tubing “selective”?Get out your dialysis tubing lab.Get out your dialysis tubing lab.

Warm Up 1-6Warm Up 1-6

Get you Part II lab set up Get you Part II lab set up Make your observations – finish lab Make your observations – finish lab

questionsquestionsTurn in your lab.Turn in your lab.Today:Today:

Begin photosynthesis chapterBegin photosynthesis chapter

Warm Up 1-7Warm Up 1-7

Get your Part II lab set upGet your Part II lab set upMake your observationsMake your observationsFinish the lab questions – Turn in LabFinish the lab questions – Turn in Lab

Today:Today:Start Photosynthesis!!Start Photosynthesis!!

Hypo / Hypertonic SolutionsHypo / Hypertonic Solutions