1. Active transport

2. Transport mechanisms Passive transport (doesn’t require energy)  Diffusion  Facilitated diffusion  Osmosis  Filtration Active transport (uses energy from ATP)  Bulk transport } Movement down a concentration gradient

3. 2. Active transport Uses chemical energy from ATP Move molecules against the concentration gradient (low conc.  high conc.)

5. Bulk Transport

7. Videos http://www.youtube.com/watch?v=_bmp2_T0c7k active transport (short) http://www.youtube.com/watch?v=K7yku3sa4Y8&NR=1 bulk transport (short)

8. Active or passive moleculesdirectionEnergy needed? Protein needed? Diffusion Facilitated diffusion Osmosis Active transport Active or passive moleculesdirectionEnergy needed? Protein needed? Diffusion PassiveSmall, hydrophobi c Down gradient (  low conc.) No Facilitated diffusion PassiveAny (transporter is specific) Down gradient (  low conc.) NoYes Osmosis PassiveWaterTowards high solute conc. No Active transport ActiveAny (transporter is specific) Specific, depends on transporter Yes (ATP used) Yes

9. MENU Key Words Exercises Quick Quiz MCQ Videos

10. Key words sovent solute solution soluble passive diffusion membrane phospholipid bilayer permeable impermeable selectively permeable concentration gradient surface area facilitated transport carrier proteins ion channels osmosis water potential active transport ATP bulk transport endocytosis phagocytosis pinocytosis hypertonic hypotonic isotonic Back to menu

11. Quick quiz 1.Solutes ____ down a concentration gradient 2.Ions are ____ (they can dissolve) in water 3.Passive transport is always ____ a concentration gradient. 4.Passive transport does not require ____ 5.Diffusion is one type of ____ transport. 6.____ diffusion requires protein carriers or ion channels 7.Facilitated diffusion does / does not require ATP 8.____ is the diffusion of water across a selectively permeable membrane 9.Water diffuses down a water ____ gradient 10.____ transport requires energy (ATP) because diffusion is ____ the concentration gradient Answers Back to menu

12. Quick quiz 1.Solutes diffuse down a concentration gradient 2.Ions are soluble (they can dissolve) in water 3.Passive transport is always down a concentration gradient. 4.Passive transport does not require energy (or ATP) 5.Diffusion is one type of passive transport. 6.Facilitated diffusion requires protein carriers or ion channels 7.Facilitated diffusion does / does not require ATP 8.Osmosis is the diffusion of water across a selectively permeable membrane 9.Water diffuses down a water potential gradient 10.Active transport requires energy (ATP) because diffusion is against the concentration gradient Back to menu

13. Exercise Workbook pp 62-6 Pathfinder pp Back to menuREADING Pathfinder p48 (or p42) Enzymes & reaction rate Excellence in Biology pp114-6

14. Videos http://www.youtube.com/watch?v=_bmp2_T0c7khttp://www.youtube.com/watch?v=_bmp2_T0c7k (Na/K pump) http://www.youtube.com/watch?v=ldRZcmppQM8&feature=rel atedhttp://www.youtube.com/watch?v=ldRZcmppQM8&feature=rel ated (transport, 8 min) http://www.youtube.com/watch?v=K7yku3sa4Y8&feature=rela tedhttp://www.youtube.com/watch?v=K7yku3sa4Y8&feature=rela ted (endo- exo-cytosis, 1 min) http://www.youtube.com/watch?v=sdiJtDRJQEc&feature=rela tedhttp://www.youtube.com/watch?v=sdiJtDRJQEc&feature=rela ted (osmosis, 1 min) http://www.youtube.com/watch?v=VUnvwrx8Wq4&feature=rel atedhttp://www.youtube.com/watch?v=VUnvwrx8Wq4&feature=rel ated (5 min) Back to menu

15. Question 1 Diffusion can normally not take place in (a) a liquid (b) a solution (c) a solid (d) a gas 27 Back to menu √

16. Question 2 Diffusion takes place as a result of (a) convection currents (b) air movements (c) natural movement of molecules (d) changes in temperature 29 Back to menu √

17. Question 3 In a plant leaf, CO 2 diffuses a)into the air space between cells, b) into the cytoplasm, c) through the cell wall, d) through a pore in the epidermis. The correct sequence is (a) a,b,c,d (b) c, b, d, a (c) d, a, c, b (d) d, c, a, b 31 Back to menu √

18. Question 4 Which of these would you NOT expect to diffuse freely through a cell membrane ? (a) carbon dioxide (b) water (c) proteins (d) oxygen 32 Back to menu √

19. Question 5 Through which of these layers would you expect diffusion to be most rapid ? (a) (b) (c) (d) 33 Back to menu √

20. Question 6 In osmosis, water will diffuse through a membrane (a) From water to a concentrated solution (b) From a concentrated solution to a dilute solution (c) From a dilute solution to a concentrated solution (d) From a dilute solution to a more dilute solution 26 Back to menu √

21. Question 7 Which statement is false ? (a) The plant cell wall is permeable to water (b) The plant cell wall is selectively permeable (c) The cell membrane is selectively permeable (d) The vacuole contains a solution of salts and sugars 27 Back to menu √

22. Question 8 concentrated solution dilute solution Cell sap more dilute solution b a c Water will tend to move by osmosis (a) from b to a and c, and from c to a (b) from c to a and b, and from a to b (c) From a to b and c, and from c to b (d) From c to b and a, and from b to c Plant cells 28 Back to menu √

23. Question 9 Which statements are correct ? (a) A fresh water fish tends to absorb water by osmosis (b) A sea water fish tends to absorb water by osmosis (c) A fresh water fish tends to lose water to its surroundings (d) A sea water fish tends to lose water to its surroundings 29 Back to menu √ √

24. Question 10 Phagocytosis requires energy because (a) it is a form of active transport (b) it is a type of bulk transport (c) it involves the membrane (d) food is absorbed against the concentration gradient

25. Correct 31 Back to menu

26. Incorrect 32 Back to menu

27. The end