Daily Warm up 9/17/10 H 1.What two things must happen for diffusion to occur? 2.Define these three words: Isotonic solution, Hypotonic, Hypertonic. (where is there more water in each scenario) 3.If your cells were to be placed in salt water what do you think would happen and why? True and False 1.Only 25% of the world is left handed? 2.Each square inch of human skin consists of twenty feet of blood vessels.

Daily Warm up 9/23/10 CP 1. Define Osmosis? 2. What happens to a cell that is hypotonic? 3. What happens to a cell that is hypertonic? 4. What two things must happen in order for diffusion to occur? 5. T/F The average adult has 5 Liters of blood in their body? 2

AFTER The warm up: 1.Grab your cups and re-measure and weigh both potatoes. 2.Make one more row on the bottom of your data sheet and record your info. 3.FINISH ALL the questions and observations in the lab- INCLUDING the graph. There is graph paper by the printer. 4.Write a paragraph that must include: 1.Summary of what you did. 2.What were the conclusions? Did you prove your hypothesis or was it wrong? Why? 3.Were there any problems in the lab that may have messed up your data? (Source of error) 4.What could you have done differently to fix the problems and make the lab more smooth next time.

4 Movement through Cell Membranes Movement through Cell Membranes- Gateway to the Cell

5 Cell Membrane controls Homeostasis insideIt balances the inside and outside of the cell. Homeostasis is maintained by plasma membrane controlling what enters & leaves the cell

6 Structure of the Cell Membrane

7 PhospholipidsCholesterolProteins Carbohydrates (glucose) Membrane Components

8 LABEL THE STRUCTURES

9Phospholipids Make up the cell membrane Contains 2 fatty acid chains called the tails Contains one glycerol called the head.

10 hydrophilic Heads are hydrophilic “water loving” hydrophobic Tails are hydrophobic “water fearing” Cell Membrane Makes membrane “Selective” in what crosses

11 Cell Membrane Hydrophobic molecules pass easily; hydrophilic DO NOT phospholipids bilayer The cell membrane is made of 2 layers of phospholipids called the lipid bilayer

12 Small molecules and larger hydrophobic molecules move through easily. e.g. O 2, CO 2, H 2 O Semipermeable Membrane

13 Ions, hydrophilic molecules larger than water, and large molecules such as proteins do not move through the membrane on their own. Semipermeable Membrane

14 Types of Transport Across Cell Membranes

15 Simple Diffusion NORequires NO energy HIGH to LOWMolecules move from area of HIGH to LOW concentration

Diffusion Two things need to happen in a cell in order for diffusion to occur… what are they? 16 1.Cell membrane must be permeable to that substance. 2.There must be a concentration gradient (needs to be higher in one area and move to lower area)

17 DIFFUSION PASSIVE Diffusion is a PASSIVE process which means no energy is used to make the molecules move, they have a natural ENERGY

STOP POINT: Diffusion of Food Coloring Demonstration. 1.EVERYONE Take out a piece of paper (# 1-3). 2.Have someone at your table put in 4 drops of the food coloring I bring around. 3.Answer these questions- without talking: 1.What happened when the food coloring was added? 2.What did the water look like before the color was added, while it was being added and once it was finished? 3.How did the water end up turning red? (tell me what the molecules were doing). 18

Sugar Cube Diffusion Answer the three questions as you watch the sugar cube in the next cup of water. 1.What happened when the sugar cube was added? 2.What did the water look like before the sugar was added, while it was being added and once it was finished? 3.Explain to me the process of diffusion and how this was an example? 19

20 Diffusion of Liquids

Sugar Cube Diffusion 21

22 Diffusion through a Membrane Cell membrane Solute moves DOWN concentration gradient (HIGH to LOW)

23 Osmosis Diffusion of water across a membraneDiffusion of water across a membrane Moves from HIGH water potential (low solute) to LOW water potential (high solute)Moves from HIGH water potential (low solute) to LOW water potential (high solute)

24 Diffusion of H 2 O Across A Membrane (Osmosis) High H 2 O potential Low solute concentration Low H 2 O potential High solute concentration 1. The left side concentration is what? 2.The right side concentration is what? So which way does water move?

3 Types of Osmosis: 25 1.Isotonic Solutions: the solute and water concentration is the same inside the cell as it is outside the cell 2.Hypertonic Solutions: Higher concentration outside the cell than inside the cell. 3.Hypotonic Solutions: Higher concentration inside the cell than outside the cell.

26 Cell in Isotonic Solution What is the direction of water movement? The cell is in _______________. equilibrium CELL 10% NaCL 90% H 2 O 10% NaCL 90% H 2 O ENVIRONMENT NO NET MOVEMENT

27 Cell in Hypotonic Solution What is the direction of water movement? Water moves into the cell CELL 10% NaCL 90% H 2 O 20% NaCL 80% H 2 O H2O

28 Cell in Hypertonic Solution What is the direction of water movement? Water moves out of the cell. CELL 15% NaCL 85% H 2 O 5% NaCL 95% H 2 O ENVIRONMENT H2O

29 Cells in Solutions

30 Isotonic Solution NO NET MOVEMENT OF H 2 O (equal amounts entering & leaving) Hypotonic Solution Water enters cell- can cause it to burst Hypertonic Solution Water leaves cell until it “deflates”

31 What will happen?

How does this relate to Anatomy? Discuss at your table this question and appoint someone to share your answer: What would happen to your blood cells if the fluid surrounding them had too much salt? 32

33 Osmosis in Red Blood Cells Isotonic Hypotonic Hypertonic

What Happens to Blood Cells? 34

35 hypotonichypertonic isotonic hypertonicisotonic hypotonic

36 STOP POINT: OSMOSIS ACTIVITY LAB At your lab tables you are working in groups of 2 or 3. Each lab table should be divided into 2 groups. WAIT FOR MY DIRECTIONS! Send one person from your group to the materials table to receive your materials. WAIT for FURTHER DIRECTIONS.

37 3 Types of Transport: 1.Simple Diffusion (also includes osmosis) 2.Facilitated Diffusion 3.Active Transport

Passive Transport vs. Active Transport Passive means: it DOES NOT require energy. Active means: it DOES require energy. Which type(s) are passive? Which type(s) are active?

39 Three Forms of Transport Across the Membrane

40 Passive Transport Facilitated diffusion  Doesn’t require energy  Uses transport proteins to move high to low concentration Examples: Glucose or amino acids moving from blood into a cell.

41 2 Types of Transport Proteins In Facilitated Diffusion- the molecules are too big and need “help” or to be facilitated across.

42 Facilitated Diffusion copyright cmassengale 1. Channel proteins are embedded in the cell membrane & have a pore for materials to cross

43 Facilitated Diffusion They bond and drag molecules through the lipid bilayer and release them on the opposite side.They bond and drag molecules through the lipid bilayer and release them on the opposite side. 2.Carrier proteins can change shape to move material from one side of the membrane to the other

44 Carrier Proteins Carrier proteins change shape to move materials across the cell membraneCarrier proteins change shape to move materials across the cell membrane

45 Active Transport  Requires energy or ATP  Moves materials from LOW to HIGH concentration  AGAINST concentration gradient

46 Active transport  Examples: Any Ions: Pumping Na + (sodium ions) out and K + (potassium ions) in.  This happens in your Nervous System!

47 Moving the “Big Stuff” Large molecules move materials into the cell by one of TWO forms of ENDOCYTOSIS Large molecules move materials into the cell by one of TWO forms of ENDOCYTOSIS.

48Pinocytosis Sometimes called “Cell Drinking” Takes in dissolved molecules as a vesicle Takes in dissolved molecules as a vesicle.

49 Pinocytosis Called cell drinking because once in the cell materials dissolve in water to be used by the cellCalled cell drinking because once in the cell materials dissolve in water to be used by the cell

50 Endocytosis – Phagocytosis Used to engulf large particles such as food, bacteria, etc. into vesicles Called “Cell Eating”

51 Phagocytosis Phagocytosis - Capture of a Yeast Cell (yellow) by Membrane Extensions of an Immune System Cell (blue)

52 Moving the “Big Stuff” Molecules are moved out of the cell by vesicles that fuse with the plasma membrane. Exocytosis This is how many hormones are secreted and how nerve cells communicate with one another This is how many hormones are secreted and how nerve cells communicate with one another.

53 Exocytosis Exocytic vesicle immediately after fusion with plasma membrane.

54 Exocytosis The opposite of endocytosis is exocytosis. Large molecules that are manufactured in the cell are released through the cell membrane. Inside Cell Cell environment

55 How does osmosis or Diffusion play a role in the human body? What is the main difference between Passive transport and Active transport? What is endocytosis and exocytosis? What happens if a red blood cell is in a hypertonic solution? Hypotonic? Isotonic? REVIEW QUESTIONS