1. Cellular Energy C HAPTER 8

2. R EVIEW  What is energy?  Can energy be created?  What are some forms of energy?  Why do living things need energy?  How do humans obtain energy?

3. T HE P HOTOSYNTHESIS E QUATION 6 C0 2 + 6 H 2 OC 6 H 12 O 6 + 6 O 2 Carbon + water sugars + oxygen dioxide Photosynthesis uses the energy from sunlight to convert water and carbon dioxide into high- energy sugars and oxygen. LIGHT

4. H OW O RGANISMS O BTAIN E NERGY  All cellular activities require ENERGY  Energy is the ability to do work  Assembly of macromolecules  Break down of macromolecules  Cell transport  Transport of genetic information

5. T RANSFORMATION OF E NERGY  Law of Thermodynamics –studies the flow of energy  First Law - Conservation of energy energy can be converted from one form to another, but it cannot be created or destroyed  Second Law of thermodynamics Energy is not converted without some loss of useable energy, typically thermal energy

6. A UTOTROPHS AND H ETEROTROPHS  Autotrophs – make their own food; most convert light energy to food  Chemotrophs – use inorganic substances as a source of energy  Heterotroph – organisms that need to ingest food to obtain energy

14. M ETABOLISM  Metabolism – ALL the chemical reactions in a cell  Two types of metabolic pathways:  Catabolic – release energy by breaking down larger molecules into smaller molecules  Anabolic – use energy to build larger molecules from smaller molecules

15. M ETABOLISM  Photosynthesis –  Anabolic pathway in which light energy from the sun is converted to chemical energy for use by the body  Cellular Respiration –  Catabolic pathway in which organic molecules are broken down to release energy

16. M ETABOLISM  Photosynthesis 6 C0 2 + 6 H 2 OC 6 H 12 O 6 + 6 O 2 ReactantsProducts  Cellular Respiration 6 O 2 + C 6 H 12 O 6 6 H 2 O + 6 C0 2

17. E NERGY F LOW Photosynthesis (autotrophs) Cellular Respiration (heterotrophs) C 6 H 12 O 6 + 6 O 2 6 C0 2 + 6 H 2 O

18. ATP ATP = ADENOSINE TRIPHOSPHATE

19. ATP  ATP provides chemical energy for cells  Composed of –  Adenine Base  Ribose Sugar  Three Phosphate Groups

20. ATP

21.  Energy is STORED in the chemical bonds between phosphate groups  Energy is RELEASED when the bond between the second and third phosphate group is broken

22. ATP/ADP  ATP releases energy when the bond between the second and third phosphate group is broken  This forms ADENOSINE DIPHOSPHATE (ADP)  Energy is stored in the phosphate bond when ADP receives a phosphate group to become ATP

23. ATP/ADP

25. Phosphate Groups

26. L IGHT E NERGY AND P IGMENT

27. L ESSON O BJECTIVES Students will be able to: 1. Explain that white light is composed of multiple colors. 2. Understand that different colors of light have different wavelengths (λ) and different amounts of energy (E). 3. List the colors of the visible light spectrum. 4. Identify which color of light has the most energy/least energy.

28. T HE E NERGY OF L IGHT

29. V ISIBLE L IGHT S PECTRUM Sunlight is composed of colors with different wavelengths ROY G BIVROY G BIVROY G BIVROY G BIV  Longer wavelengths (red/orange) have lower energy than shorter wavelengths (violet/indigo)  E = hc/λ  where E = energy, h = Planck’s constant, c = speed of light, and λ = wavelength

30. E LECTROMAGNETIC S PECTRUM

31. L ESSON 2: O BJECTIVES Students will be able to: 1. Define work. 2. Understand that light energy can be converted into other forms of energy. 3. Explain the THREE options for light energy when it meets an object. 4. Define pigment. 5. Identify THREE pigments found in plants and tell which colors of light each pigment absorbs.

32. L IGHT D OES W ORK ! Work – force times the distance through which it acts. W = F x d Can light do work? Crookes Radiometer Video

33. Absorbed Reflected Transmitted

36. P LANT P IGMENT C HROMATOGRAPHY HOMEWORK:  Lab tomorrow – requires goggles and apron  Read laboratory packet  View pre-lab video on YouTube http://www.youtube.com/watch?v=THqmpLdUaBA&feature=related http://www.youtube.com/watch?v=THqmpLdUaBA&feature=related

37. W ORK C ITED "Electromagnetic Spectrum." 25 January 2010. Ronk. "My Perpetual Motion Machine." 20 September 2009. Weekends in Paradelle. 27 January 2010. "work." The American Heritage® New Dictionary of Cultural Literacy, Third Edition. Houghton Mifflin Company, 2005. 26 Jan. 2010.. http://dictionary.reference.com/browse/work