CELL MEMBRANE

How is the environment connected to the Cells?

Video

Review: Remember ChemistryWhat does polar mean?

Polar means a molecule has a positive and negative end

How do polar molecules behave?• (“like dissolves like”)

Polar molecules attract to other polar molecules• Polar molecules do not

attract nonpolar molecules.

Basic Structure

What do you need to know?

Phospholipids• arranged in a double layer called a bilayer.• Phospholipids are polar molecules. • Positive

(hydrophilic = water loving) : head

• Negative (hydrophobic = water hating) : tail

Cell FunctionWhat do cells need to get in and out to function

properly? Molecules:

CO2 (Carbon Dioxide) = Nonpolar, small molecule O2 (Oxygen) = Nonpolar, small molecule H2O (Water) = Polar, small molecule C6H12O6 (sugars/glucose) = Nonpolar, large molecules Amino Acids (building block of proteins) = typically Nonpolar,

large molecules Nucleic Acids (building blocks of DNA) = typically Nonpolar,

large molecule Lipids (Called fatty acids) = typically Nonpolar, large molecule Ions = Charged molecules that need to get into or out of the cell

Learn

Pair

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Jig-saw: Cell Membrane Function

6 ways molecules move 1. Diffusion (p. 74-75)2. Osmosis (p. 76-77)3. Facilitated Diffusion (p.

80)4. Sodium-Potassium Pump

(p. 81-82)5. Endo- & Exocytosis (p.

83)6. Membrane Receptor

Proteins (p. 84-86)

Assignment:1. Class number off 1

through 6.2. ID specific

responsibilities based on your number.

3. Read the text Take notes on what is

the important must knows.

Jig-saw: Cell Membrane Function

6 ways molecules move 1. Diffusion (p. 74-75)2. Osmosis (p. 76-77)3. Facilitated Diffusion (p.

80)4. Sodium-Potassium Pump

(p. 81-82)5. Endo- & Exocytosis (p.

83)6. Membrane Receptor

Proteins (p. 84-86)

Assignment:4. Get in to groups based

on your assigned number. Discuss the must knows from the reading.

5. Each member draw a picture expressing the must knows. “No Words”

6. Plus discuss a real world application of this process.

Jig-saw: Cell Membrane Function

6 ways molecules move 1. Diffusion (p. 74-75)2. Osmosis (p. 76-77)3. Facilitated Diffusion (p.

80)4. Sodium-Potassium Pump

(p. 81-82)5. Endo- & Exocytosis (p.

83)6. Membrane Receptor

Proteins (p. 84-86)

Assignment:7. Get into groups with

people of your non number. We are going to go with 5 groups.

8. Teacher/student Each person is

responsible for teaching their part.

Everyone is taking notes and copying the illustration.

Lab

Experiment 11. Fill sandwich bag with 20

mL of Iodine rap rubber band around opening

2. Fill plastic cup w/ 20 mL of Starch solution.

3. Place bag in beaker so opening is outside the beaker

4. Let stand until next class

Experiment 21. Fill sandwich bag with 20

mL of Starch solution rap rubber band around opening

2. Fill plastic cup w/ 20 mL of Iodine.

3. Place bag in beaker so opening is outside the beaker

4. Let stand until next class

Obtain…1. 2 sandwich bags2. 2 plastic cups3. 2 rubber bands

Iodine/Starch Lab Observations Draw a picture of the before and after for

each experiment. Write a TELL-Con about the experiment.

Answer the questions has evidence. Do both molecules move through the bag? What is it about the structure of a each molecule

that determine whether of not it move through the bag?

I2 Starch = Several glucose (C6H12O6) molecules attached to

one another What molecule(s) moves into the bag and why?

What are the keys to getting across the cell membrane?

Size Polarity Concentration

Vocabulary that is good to know Solution

Solute (sugars or salts) Solvent (water)

Concentration Gradient If there is a lot of solute = high concentration If there is little solute = low concentation

If you move with the concentration gradient High Low If you move against the concentration gradient Low

High When the concentrations are equal we call that

equalibrium.

Passive v. Active Transport Passive Transport

No energy needed Moves with the concentration gradient

Active Transport Requires energy Moves against concentration gradient

Let’s start with Nonpolar, Small molecules

Diffusion Passive Transport Movement of

molecules from a high concentration to a low concentration. Ex. A Fart!

With the cell membrane diffusion occurs through phospholipids

Let’s talk about water(Nonpolar, small molecules)

Osmosis Passive Transport Movement of water

from a high concentration to a low concentration. Ex. Bounty paper

towel Water move through

the phospholipids

Terms to know about Osmosis

Hypotonic The lower

concentration of solute

Hypertonic The high

concentration of solute

Isotonic Concentration of

solute is equal on both sides

Link to Animationhttp://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_osmosis_works.html

Write TELL-Con on Egg Demo Use the information learned over the

past two slides to answer what happens in the Egg Demo.

Let’s talk about Large molecules moving with concentration gradient

Facilitated Diffusion

Passive Transport

Because it is a large molecule it will need an opening to get through. A carrier protein.

Link to Animationhttp://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_facilitated_diffusion_works.html

Ion Channel TransportIons (charged

molecule) Passive Transport

Special channel needed to get charged molecules into and out of the cell with the concentration gradient

Click Here for Animation

Let’s talk about movement against the concentration gradient.

Active Transport Needs Energy

Need to know the sodium/potassium

Link to Animationhttp://www.brookscole.com/chemistry_d/templates/student_resources/shared_resources/animations/ion_pump/ionpump.html

Receptors Proteins

Click here for video

Form of active transport

Endo- and ExocytosisPassive transport Endo- = “in” Exo- = “out”

cyto- = “cell”

-osis = “process”

What is Endocytosis?What is Exocytosis?

Click here for animationhttp://www.maxanim.com/physiology/Endocytosis%20and%20Exocytosis/Endocytosis%20and%20Exocytosis.htm

Cell Transport

Click here for the video!