Table of Contents

1. Chapter 5 Homeostasis and Cell Transport Table of Contents Section 1 Passive Transport Section 2 Active Transport

2. Section 1 Passive Transport Chapter 5 Objectives • Explainhow an equilibrium is established as a result of diffusion. • Distinguishbetween diffusion and osmosis. • Explain how substances cross the cell membrane through facilitated diffusion. • Explainhow ion channels assist the diffusion of ions across the cell membrane.

3. Section 1 Passive Transport Chapter 5 Diffusion • Passive transport involves • Diffusionis the movement of molecules from an • area of __________________ concentration to an area of __________________ concentration, driven by the molecules’ kinetic energy until equilibrium is reached.

4. Diffusion • Concentration Gradient – • Equilibrium – • Once equilibrium is reached, molecules move randomely.

5. Section 1 Passive Transport Chapter 5 Diffusion, continued • Diffusion Across Membranes • Molecules can diffuse across a cell membrane by

6. Section 1 Passive Transport Chapter 5 Diffusion

7. Section 1 Passive Transport Chapter 5 Osmosis • Osmosisis the

8. Section 1 Passive Transport Chapter 5 Osmosis, continued • Direction of Osmosis • The net direction of osmosis is determined by the

9. Section 1 Passive Transport Chapter 5 Osmosis, continued • Direction of Osmosis • When the solute concentration outside the cell is higher than that in the cytosol, the solution outside is_________________to the cytosol, and water will

10. Section 1 Passive Transport Chapter 5 Osmosis, continued • Direction of Osmosis • When the solute concentrations outside and inside the cell are equal, the solution outside is___________________, and there will be no net movement of water.

11. Section 1 Passive Transport Chapter 5 Hypertonic, Hypotonic, Isotonic Solutions

12. Section 1 Passive Transport Chapter 5 Osmosis, continued • How Cells Deal With Osmosis • To remain alive, cells must compensate for the water that enters the cell in hypotonic environments and leaves the cell in hypertonic environments. • Contractile vacuoles are organelles that

13. Osmosis, continued • In hypotonic solutions, water moves into plant roots and exerts pressure within the cells this is called________________________. • In hypertonic solutions, water leaves the cells of plants and the cell shrinks and wilts. This condition is called_______________________.

14. Section 1 Passive Transport Chapter 5 Facilitated Diffusion • In facilitated diffusion, a molecule • The carrier protein then changes its shape and transports the molecule down its

15. Section 1 Passive Transport Chapter 5 Facilitated Diffusion

16. Section 1 Passive Transport Chapter 5 Diffusion Through Ion Channels • Ion channelsare proteins, or groups of proteins, that provide

17. Section 1 Passive Transport Chapter 5 Ion Channels

18. Section 2 Active Transport Chapter 5 Objectives • Distinguish between passive transport and active transport. • Explainhow the sodium-potassium pump operates. • Compareendocytosis and exocytosis.

19. Section 2 Active Transport Chapter 5 Cell Membrane Pumps • Active transportmoves molecules across the cell membrane from an area of • Unlike passive transport, active transport requires

20. Section 2 Active Transport Chapter 5 Cell Membrane Pumps, continued • Some types of active transport are performed by carrier proteins called

21. Section 2 Active Transport Chapter 5 Cell Membrane Pumps, continued • Sodium-Potassium Pump • The sodium-potassium pumpmoves ___________ ________ ions into the cell’s external environment for every __________ __________ ions it moves into the cytosol. • ___________ supplies the energy that drives the pump.

22. Section 2 Active Transport Chapter 5 Sodium-Potassium Pump

23. Section 2 Active Transport Chapter 5 Movement in Vesicles • Endocytosis • In ________________________, cells ingest external materials by folding around them and forming a pouch. • The pouch then pinches off and becomes a membrane-bound organelle called a _____________________.

24. Section 2 Active Transport Chapter 5 Movement in Vesicles, continued • Endocytosis • Endocytosis includespinocytosis, in which the • vesicle contains _________________ or • __________________, and phagocytosis, in • which the vesicle contains

25. Section 2 Active Transport Chapter 5 Movement in Vesicles, continued • Exocytosis • In exocytosis, vesicles made by the cell fuse with the cell membrane,

26. Section 2 Active Transport Chapter 5 Endocytosis and Exocytosis

27. Section 1 Passive Transport Chapter 5 Osmosis