Watch the animation, then state the process being shown

1. Watch the animation, then state the process being shown

7. What process was shown?

8. What is diffusion? The movement of substances down a concentration gradient from a region of high concentration to a low concentration Describe what happened in the animation

9. Watch the next animation and state what process is shown

10. Water molecules Extracellular space Cell membrane Intracellular space

11. Extracellular space Intracellular space

12. Extracellular space Intracellular space

13. Extracellular space Intracellular space

14. Extracellular space Intracellular space

15. Extracellular space Intracellular space

16. Extracellular space Intracellular space

17. Extracellular space Intracellular space

18. Extracellular space Intracellular space

19. Extracellular space Intracellular space What process was shown? Describe what happened in the animation Why did the water molecule use a channel protein and not just cross straight through the lipid bilayer?

20. What is osmosis? The diffusion of water across a selectively permeable membrane from a high concentration to a low concentration

21. Why does diffusion/osmosis occur? • Organisms must maintain homeostasis and diffusion/osmosis allows cells to receive necessary nutrients and release unwanted waste

22. What is needed in mammalian cells?

23. Why are so many nutrients needed for mammalian cells? • Because mammals have several different cells that perform different tasks and would require different nutrients to perform those tasks

24. Cellular Transport in other organisms How osmosis works

25. Osmosis in an Elodea Leaf • Elodeais a common freshwater plant that is frequentlyused to decorate aquariums. • Freshwater is hypotonic to Elodea and maintains normal osmotic pressure (internal pressure) in the plant.  • A hypotonic solution is a solution that contains less (hypo) solutes than the cytoplasm of the cell. • Thus, a hypotonic solution has more water than the celland water has a tendency to move (diffuse) into the cell. • Plant cells do not rupture because the cell walls resist the outward expansion of the plasma membrane.

26. What happens to Elodea in a hypotonic solution? Osmotic pressure increases because water enters the cell

27. Osmosis in an Elodea Leaf • A hypertonic solution is a solution that contains more (hyper) solutes than the cytoplasm of the cell. • Thus, a hypertonic solution has less water than the celland water has a tendency to move (diffuse) out of the cell. • Plant cells do not shrivel because the cell walls resist the inward decrease of the plasma membrane.

28. What happens to Elodea in a hypertonic solution? Osmotic pressure decreases because water leaves the cell

29. Water will continue to move mostly into or out of a cell until it has reached equilibrium • Once the cell has reached equilibrium or homeostasis, water continues to move in both direction

30. Osmosis in human blood cells

31. What happens to a red blood cell in an Isotonic solution? It means you have an equal amount of solute inside and outside the cell 10% salt 10% salt Red blood cells Plant cell

32. What happens to a red blood cell in a Hypotonic solution? Because there is only a cell membrane the blood cell could burst 10% salt 20% salt Red blood cells Plant cell

33. What happens to a red blood cell in a Hypertonic solution? Red blood cells will shrivel up because the cell membrane does not provide enough support 20% salt 10% salt Red blood cells Plant cell

34. Osmosis in Paramecium Paramecia are freshwater protozoa (single-celled eukaryotes) found in pond water • Freshwater is hypotonic to Paramecium, and results in the osmotic movement of water into the cell. • Specialized organelles called contractile vacuoles function in the homeostatic maintenance of normal osmotic pressure

35. Paramecium Contractile vacuoles

36. Paramecium

37. Types of Diffusion Passive diffusion and Active diffusion

38. Facilitated Diffusion a form of Passive Diffusion • Movement of molecules such as glucose and water through the cell membrane using channel and carrier proteins • Does not require the input of energy • Example: osmosis

39. Active Transport • Movement of material from low concentration to high concentration or against the concentration gradient • Requires energy

40. concentration gradient high high low low With the concentration gradient Is energy input needed? Against the concentration gradient Is energy input needed?

41. Movement of nutrients and waste across the cell membrane

42. Endocytosis/phagocytosis • A type of active transport that moves large amounts of material into the cell • Endo= into Cyto= cell • Another type of active transport removes large amounts of materials out of the cell • Exo= out of Cyto= cell Exocytosis