Observe the three pictures of red blood cells. 1) Draw one cell of each picture and describe the cells. 2) Predict: Which cells was placed in low, medium and high salt solution? Explain. 3) Conclude: Why is it important to have a specific salt concentration in the blood?

Before: To clarify: Placed in hypotonic, hypertonic, Isotonic solutions. After: The inside and outside solutions are isotonic to one another.

Plant cell??

Suppose your dialysis tubing is replaced with a living fish… What would happen to this fish if you placed it in tap or even in distilled water? What would happen to this fish if you placed it in salt water? So, how do some fish live in freshwater, or in saltwater?

Passive and Active Transport Across the Cell Membrane

Two Molecules thick membrane From Paramecium to Facilitated Diffusion

Passive Transport Molecules flow down their concentration gradient. Transport that doesn’t use cell energy.

Passive Transport 1.Simple Diffusion Example: Water , oxygen Cell Membrane, Passive Transport, wandering molecules Passive Transport 1.Simple Diffusion Example: Water , oxygen 2. Facilitated Diffusion Example: Glucose, Ions

Passive Transport Channels by Stolaf

Diffusion: EQUILIBRIUM Glucose cannot pass through Osmosis Glucose Channels by Stolaf Passive Active Transport! Glucose

Facilitated Diffusion Glucose Channels open in response to the hormone Insulin EQUILIBRIUM Glucose Transporter Tutorial: Passive and Active Transport

Lets compare: Diffusion (of oxygen, for exmaple) 2. Osmosis 3. Facilitated Diffusion

1.Direction 2.Energy Source 3. What’s moving? 4.Protein? oC Notes + - Comparing In terms of: 1.Direction 2.Energy Source 3. What’s moving? 4.Protein? Osmosis Diffusion   O2… H2O   oC Notes     + - Glucose  Facilitated Diffusion

A. B. Copy and Identify: Which is going down, which up the concentration gradient? Predict: where will the substance go, by passive transport? Explain

Active Transport Transport that pushes ions up / against their concentration gradient. Transport that requires cell energy. Notes

2. Endocytosis (Large particles) 3. Exocytosis (Large particles) Active Transport Ion Pumps – ATP Antiport Ion Pumps - 1. Pumps (Charged Ions) 2. Endocytosis (Large particles) 3. Exocytosis (Large particles)

Ion Pumps Maintain a membrane potential with a more negative ions inside and more positive ions outside. Transport Animation (password) Active Transport Animation Tutorial Pumps - by Stolaf Na/K pump simple animation

Endocytosis Endocytosis of LDL Endocytosis Phagocytosis Simplified Endocytosis White Blood Cell Chases Bacteria

Exocytosis Exocytosis animation

A. B. Identify: Passive, active transport, pumps and channels.

Try yourself - Active or Passive? Transport Animation (and more!) Diffusion Channel Osmosis Antiport Symport Symport

Where would the water go? 2. What would be the problem for the cell? A living cell is put into a surrounding of 100% pure water (most hypotonic!!) – Where would the water go? 2. What would be the problem for the cell? 3. How might the cell solve it? J. Contractile vacuole Movie Contractile Vacuole new Contractile Vacuole UC Davis

Video: Part Two

Raise The Correct Note in response to the following slides: Passive Transport: Blue Active Transport: Red Both: Blue and Red

1. Going from Low to High concentration 2. Uses ATP as source of (cellular) energy 3. Small, uncharged substances

5. Going from High to Low concentrations 4. Proteins are involved 5. Going from High to Low concentrations 6. Ion Channels and Glucose Transporter

7. Ion Pumps 8. Uses Heat as the source of (kinetic) energy 9. Osmosis is an example of….

10. Charged substances (ions). 11. Endocytosis / Exosytosis 12. Demonstrated by dialysis tubing

ATP 13. ADP

14. ATP

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16.

17.

18. Oxygen Diffusion into cells

19.

20. Demonstrated by the decalcified egg experiment

21.

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17. ATP

19.

Transport of Proteins Inside the Cell: Vesicular Transport Problem: How do we get a new protein from the center of the cell to the membrane? ? N Solution: Vesicular Transport Protein Transport - ER and Golgi

Answer to journal: Endocytosis: Purpose is to take in liquids or a large particle, as a signal for the cell. Exocytosis: Purpose is to release a large molecule from the cell, to get rid of waste or to release a signal protein.

The cell membrane is said to be Selective and Semi-permeable. (or ‘selectively permeable’) Write at least three facts you learned that support this idea.

Consider a certain concentration of salt in water. This solution can be both hypotonic and hypertonic at the same time. How is this possible?! Hyper- tonic to Hypo- tonic to

Desalination Plant.

1. Water flows in from the estuary or sea 2. Salt water contains sodium and chloride ions 3. Pressure is applied to force salt water through membrane 4. Semi-permeable membrane with millions of microscopic holes 5. Clean water fit for drinking 6. Saline concentrate flows out

You have just learned that water moves from lower to higher solute concentration. 1.How is it possible to drive water in the opposite direction? Give an example. 2. Active transport – uses consumed energy. Passive transport – does not. What is desalination, then?