Diffusion and Transport
-
Upload
aracely-trey -
Category
Documents
-
view
28 -
download
0
description
Transcript of Diffusion and Transport
![Page 1: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/1.jpg)
Diffusion and Transport
Ms. KlinkhachornNovember 29, 2010
AP Biology
![Page 2: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/2.jpg)
Announcements:
• Quiz on THURSDAY– Organelles– Eukaryotes and Prokaryotes– Plant Cells and Animal Cells– Membranes– Passive Transport
![Page 3: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/3.jpg)
Identify the Parts
![Page 4: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/4.jpg)
Phospholipid Bilayer - Characteristics
![Page 5: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/5.jpg)
Permeability of the Bilayer
• Hydrophobic molecules can pass through, but hydrophilic molecules can not (at least not easily)– Polar molecules = hydrophilic• Examples: Sugars, charged atoms (K+) and molecules
– Nonpolar molecules = hydrophobic• Examples: oxygen, carbon dioxide
![Page 6: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/6.jpg)
Transport Proteins
• Help materials that are big or hydrophilic pass through the membrane easily– Substance specific• If it’s supposed to translocate water and sugar, it will
only translocate water and sugar
• Two Kinds:– Channel Proteins– Carrier Proteins
![Page 7: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/7.jpg)
Transport Proteins
![Page 8: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/8.jpg)
Efficacy of Transport Proteins
• 3 billion water molecules can move across the membrane using an aquaporin per second
• Glucose moves across the membrane 50,000x faster with a transport protein than by itself
![Page 9: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/9.jpg)
Passive Transport
• Diffusion ACROSS A MEMBRANE– Diffusion = movement of molecules so that they
spread out evenly in an available space • Does NOT require energy or use a transport protein• Once the molecules spread out they are in a state of
equilibrium
• Substances diffuse from a high concentration to a low concentration– They move down their own concentration
gradient
![Page 10: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/10.jpg)
Diffusion of Sugar
![Page 11: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/11.jpg)
Concentration Gradient
![Page 12: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/12.jpg)
Types of Passive Transport
• Simple Diffusion• Facilitated Diffusion• Osmosis
![Page 13: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/13.jpg)
Example: Gas Exchange
![Page 14: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/14.jpg)
Simple Diffusion
![Page 15: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/15.jpg)
Facilitated Diffusion
• Diffusion that requires a transport protein
![Page 16: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/16.jpg)
Osmosis
• Diffusion of water across a selectively permeable membrane (where the solute cannot go through the membrane)
• Water will move from an area of lower solute concentration to an area of higher solute concentration– Wants to balance out the solute concentrations
![Page 17: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/17.jpg)
Osmosis
![Page 18: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/18.jpg)
Hypertonic Solutions
• “Hyper” means “above”• A hypertonic solution has a higher
concentration of solute– This means that water is less concentrated
• A cell placed in a hypertonic solution will SHRINK due to water loss.
![Page 19: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/19.jpg)
Plant Cells in a Hypertonic Solution
![Page 20: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/20.jpg)
Before and After
![Page 21: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/21.jpg)
Hypotonic Solutions
• “Hypo” means “below”• A hypotonic solution has a lower
concentration of solute– This means that water is more concentrated
• A cell placed in a hypotonic solution will SWELL due to water intake.
![Page 22: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/22.jpg)
Isotonic Solutions
• “Iso” means “equal”• An isotonic solution has an equal
concentration of solute• A cell placed in an isotonic solution will remain
unchanged• There will still be movement of water, though
there is NO NET GAIN.
![Page 23: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/23.jpg)
DNA – November 30, 2010
Answer these on the back of your study guide:1. What is diffusion? How is it different from
passive transport?2. What do the word forms “hypo”, “hyper”,
“osmo” and “iso” mean?3. Describe what is happening in the picture.
![Page 24: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/24.jpg)
Water Balance in Animal Cells
• If the cell swells too much, it can burst. – This is called lysis. The cell lyses.
• If the cell shrivels too much, it can die.
![Page 25: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/25.jpg)
Examples (Animal Cell)
![Page 26: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/26.jpg)
Water Balance in Plant Cells• Cells still swell in hypotonic environment, but the
wall is more rigid.– Water uptake makes the cell turgid (firm).
• This is a plant’s healthy state.• If the cell is in an isotonic environment, it is
flaccid (limp)• If the cell is in a hypertonic environment, it
plasmolyzes (a process called plasmolysis)– The cell membrane pulls away from the cell wall as
water is lost– Can cause death.
![Page 27: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/27.jpg)
Examples (Plant Cell)
![Page 28: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/28.jpg)
Saltwater fish – Predict what happens to fish in these environments.
![Page 29: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/29.jpg)
Saltwater Fish
• Saltwater fish are constantly swimming in a hypertonic environment
• Fish are consistently losing water from their bodies
• In order to maintain water balance, the fish have to drink a lot of saltwater and pump salt out of their bodies
![Page 30: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/30.jpg)
Freshwater fish – Predict what happens to fish in these environments.
![Page 31: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/31.jpg)
Freshwater Fish
• Freshwater fish live in a hypotonic environment
• Water is constantly moving into their cells
• These fish pee regularly in order to get rid of this water
![Page 32: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/32.jpg)
Osmoregulation
• Osmoregulation = the control of water balance
• Certain organisms are adapted to deal with this– Sea animals – Paramecium
![Page 33: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/33.jpg)
Paramecium
• Paramecium lives in pond water, which is hypotonic to the cell.
• What effect does the hypotonic environment have on this?
• How might the paramecium adapt?
![Page 34: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/34.jpg)
Contractile Vacuole
![Page 35: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/35.jpg)
DNA – December 1, 2010
1. Give an example of how organisms have adapted to deal with hypertonic or hypotonic living conditions.
2. Explain what a hypertonic and a hypotonic environment will do to a piece of celery.
![Page 36: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/36.jpg)
Osmosis Practice
![Page 37: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/37.jpg)
Active Transport
• Active transport = movement of substances AGAINST their concentration gradient– Requires energy ATP– Uses a transport protein, specifically a carrier
protein
• This allows cells to maintain certain solute concentrations
![Page 38: Diffusion and Transport](https://reader035.fdocuments.us/reader035/viewer/2022062321/56813923550346895da0c7f1/html5/thumbnails/38.jpg)
Sodium-Potassium Pump