1. Chapter 5: The Working Cell **This Power Point Presentation can be found on my eBoard**

2. Energy and the Cell Energy – The ability to do work Kinetic Energy – Energy of movement Potential Energy – Stored energy Heat – The energy associated with the movement of molecules in a body of matter. It is a type of kinetic energy Chemical Energy – Potential energy found in the bonds of molecules

3. What forms of energy are these?

4. Laws of Thermodynamics Thermodynamics – study of the energy transformations that occur in a collection of matter (“a system”) –Systems can be closed or open If the system exchanges energy with a surrounding environment, it is open If it does not, then it is closed

6. Laws of Thermodynamics Examples of Open Systems A human body Examples of Closed Systems Greenhouse

7. Laws of Thermodynamics First Law “Law of Conservation of Energy” -Energy cannot be created or destroyed; only transformed

8. Laws of Thermodynamics How is this picture showing the First Law?

9. Laws of Thermodynamics Second Law –Energy conversions increase entropy Entropy - The amount of disorder in a system

10. Laws of Thermodynamics This block shows Order.This block shows Entropy.

11. Laws of Thermodynamics What does this picture show in relation to thermodynamics and systems?

12. Laws of Thermodynamics

13. What does it all mean for Biology? –Cells cannot transfer or transform energy with 100% efficiency –Heat always escapes as leftover energy When light energy is converted to chemical energy When chemical energy is converted to kinetic energy

14. Two Types of Reactions Endergonic Reaction –Requires a net input of energy –Low-energy reactants make high-energy products

15. Two Types of Reactions Exergonic Reaction –Requires a net output of energy –High-energy reactants make low-energy products

16. Two Types of Reactions Cellular RespirationPhotosynthesis Know the products and reactants for Cellular Respration and for Photosynthesis.

17. Two Types of Reactions The products from one reactions become the reactants for the other..

18. Energy Coupling Using the energy released from an exergonic reaction to drive an endergonic reaction

19. Energy Coupling Hydrolysis of ATP allows a phosphate group to be available to drive many cell reactions.

20. Enzymes Proteins that speed up chemical reactions by lowering the activation energy

21. Enzymes Proteins that speed up chemical reactions by lowering the activation energy

22. Enzymes – Competitive Inhibition (a) Is the NORMAL Reaction; (b) is with a Competitive Inhibitor

23. Enzymes – Noncompetitive Inhibition (a) Is the NORMAL Reaction; (b) is with a Noncompetitive Inhibitor

24. Enzymes – Negative Feedback Control Making enough of the end product should stop Enzyme 1 from doing its job.

25. Membrane Structure and Function Cell Membrane –Selective Permeability It allows some substances to cross more easily than others It blocks passage of some substances altogether

26. Membrane Structure and Function Cell Membrane –Selective Permeability

27. Membrane Structure and Function Cell Membrane –Phospholipids

28. Membrane Structure and Function Cell Membrane –Fluid Mosaic “Fluid” because the proteins and phospholipids can drift laterally in the membrane. “Mosaic” because it has diverse proteins embedded in a framework or phospholipids

29. Membrane Structure and Function Cell Membrane –Fluid Mosaic

30. Membrane Structure and Function Cell Membrane –Fluid Mosaic –http://www.youtube.com/watch?v=Qqsf_UJcf Bchttp://www.youtube.com/watch?v=Qqsf_UJcf Bc

31. Membrane Structure and Function Cell Membrane –Selective Permeability

32. Membrane Structure and Function Transporting Materials into the Cell –Diffusion Movement of substances into the cell or out of the cell without the use of energy The movement is always from high concentration to low concentration Concentration gradient – The spread of different concentrations of a substance across space. Equilibrium – The even distribution of substance across an area or space.

33. Membrane Structure and Function Transporting Materials into the Cell –Diffusion

34. Membrane Structure and Function Transporting Materials into the Cell –3 Types of Passive Transport Diffusion (already discussed this one) Facilitated Diffusion (diffusion with a “helper”) Osmosis

35. Membrane Structure and Function Transporting Materials into the Cell –Why can’t water gets past the phospholipids of the cell membrane? –Hint: Take a look at your notes about the structure of a phospholipid and hypothesize why.

36. Membrane Structure and Function Transporting Materials into the Cell –Osmosis: The movement of WATER from an area of [low solute] to [high solute]. –In other words: Water “stalks” Solute!

37. Membrane Structure and Function Transporting Materials into the Cell – Three Osmotic Situations

38. Membrane Structure and Function Transporting Materials into the Cell Questions 23 – 26 in the Notes will be answered in class on the Board. Please see me if you miss these questions and are unsure of how they should be answered.

39. Membrane Structure and Function Transporting Materials into the Cell –Facilitated Diffusion (PASSIVE) The movement of particles from [high] to [low] using a membrane protein. Otherwise the particle would not get in or out of the cell.

40. Membrane Structure and Function Transporting Materials into the Cell –Active Transport Requires Energy Spends ATP Works AGAINST the concentration gradient –Goes from [low] to [high] Classic Example: The Sodium-Potassium (Na + K + ) Pump in a cell –Works to send 3 Na + OUT and 2 K + IN the cell

41. Membrane Structure and Function Transporting Materials into the Cell –Active Transport

42. Membrane Structure and Function A Final Word on Energy Coupling… CO 2 & H 2 O O 2 & C 6 H 12 O 6