Mini-Unit Sections 3-4 & 3-5

1. Mini-Unit Sections 3-4 & 3-5 • Sections 3-4 & 3-5: • Active vs. Passive Transport

2. 3.5 Active Transport, Endocytosis, and Exocytosis • KEY CONCEPT- Cells use energy to transport materials that cannot diffuse across a membrane.

3. 3.5 Active Transport, Endocytosis, and Exocytosis • Objectives for section 3-5 • Explain how proteins transport materials against the concentration gradient • Differentiate between exocytosis and endocytosis

4. 3.5 Active Transport, Endocytosis, and Exocytosis • Active transport requires energy input from a cell and enables a cell to move a substance against its concentration gradient. • Powered by chemical energy (ATP). • Occurs through transport protein pumps.

5. 3.5 Active Transport, Endocytosis, and Exocytosis • Cells use active transport to maintain homeostasis. • Sodium/Potassium ATPase pump (Na+/K+ ATPase pump) • Important in animal cells (especially in neurons or nerve cells) • Pumps three sodium ions (Na+) OUT • Pumps two potassium (K+) INTO cell • Both AGAINST their conc. gradient & powered by ATP

7. 3.5 Active Transport, Endocytosis, and Exocytosis • Outside cell • inside cell

8. 3.5 Active Transport, Endocytosis, and Exocytosis • A cell can import and export large materials or large amounts of material in vesicles during the processes of endocytosis and exocytosis. • Cells use energy to transport material in vesicles. • Endocytosis is the process of taking material into the cell.

9. 3.5 Active Transport, Endocytosis, and Exocytosis • Two (3) types of endocytosis • Phagocytosis is where cell membrane engulfs large particles • “Cell eating” • Immune • system

10. 3.5 Active Transport, Endocytosis, and Exocytosis • Pinocytosis is where cell membrane engulfs extracellular fluid in a vesicle • “Cell drinking”

11. Pinocytosis • 3-5: Phagocytosis vs. Pinocytosis vs. Phagocytosis

12. 3.5 Active Transport, Endocytosis, and Exocytosis • Exocytosis is the process of expelling material from the cell • Messages from brain to cells via nerves

13. 3.5 Passive vs. Active Transport • & Osmosis Low conc High conc • no energy • Uses Carrier protein • Na+/K+ ATPase pump High conc Low conc • Requires energy (ATP) • Uses Carrier protein

14. Crash Course Biology #5 – Membranes and Proteins

15. Quick Quiz Time • 3-5 Quick Quiz • Each question will be worth 2 points • You may NOT talk and/or communicate with a classmate • Scores will be collected and recorded at the end of the chapter

16. 3-5 Quick Quiz • 4. Unlike passive transport, active transport requires • Concentration gradients • Diffusion • Energy from the cell • vesicles

17. 3-5 Quick Quiz • 5. Cells use active transport proteins to • Obtain molecules they need • Break down molecules • Engulf large particles • Detect the charge of molecules

18. 3-5 Quick Quiz • 6. Which process is used to release insulin from pancreatic cells into the bloodstream? • exocytosis • endocytosis • Facilitated diffusion • Sodium/Potassium ATPase pump

19. Trade your paper with a non-lab partner

20. 3-5 Quick Quiz • 4. Unlike passive transport, active transport requires • Concentration gradients • Diffusion • Energy from the cell • vesicles

21. 3-5 Quick Quiz • 5. Cells use active transport proteins to • Obtain molecules they need • Break down molecules • Engulf large particles • Detect the charge of molecules

22. 3-5 Quick Quiz • 6. Which process is used to release insulin from pancreatic cells into the bloodstream? • exocytosis • endocytosis • Facilitated diffusion • Sodium/Potassium ATPase pump

23. End of 3.5 • End of show