1. Chapter 8 Energy in a Cell What you will Learn You will learn what ATP is. You will explain how ATP provides energy for the cell. You will describe how chloroplasts trap the sun’s energy to make ATP and complex carbohydrates. You will compare ATP production in mitochondria and chloroplasts.

2. ATP in a Molecule Cell Energy; essential to life ▪Work and need for energy ▸ All living organisms must be able to produce energy from the environment. ▸ Store energy for future use. ▸ Use energy in a controlled manner. ▪Processes that require energy ▸ Active transport, cell division, muscles contracting, etc..

3. Energy source in cells ATP adenosine triphosphate ▪ATP is composed of an adenosine molecule with 3 phosphate groups attatched ▸ Phosphate groups are charged molecules.

4. Forming and Breaking Down ATP ▪The charged phosphate groups act likepositive poles of two magnets. ▸ Hard to attrack two with the same charges, takes a lot of energy (ADP, adenosine diphosphate). ▸ Tremendous amount of energy to attrack the third phosphate group. –The thrid one wants to get away and when it does the bond is broken releasing a great amount of energy. ▸ The energy from the ATP becomes available and the resulting molecule is ADP which can attrack another phosphate group to make ATP and the whole cycle starts over.

5. Page 229

6. Tapping the energy stored in ATP ▪When energy is released, cells must have a way to capture the energy or it is wasted. ▪Celluar proteins have a specific site where ATP can bind. ▪When the third phosphate group s bond is broken, the cell can capture the energy released and use the energy.

7. Figure 9.3 Page 229

8. Uses of the Cell Energy ▪Making new Molecules. ▪Cell Reproduction. ▪Maintaining homeostasis. ▪Kidney functions ▪Exercising.

9. PHOTOSYNTHESIS Trapping the Sun’s Energy ▪Process plant’s use to trap the sun’s energy and build carbohydrates, glucose, that store energy. ▪Two phases: ▸ light-dependent reactions ▸ light-independent reactions

10. Light-Dependent Reactions ▪Light-dependent reactions converts light energy into chemical energy, ATP. ▪Reactions take place in the thylakoid discs inside the chloroplasts. ▸ The pigment chlorophyll (a and b) absorb most color wavelengths except green. Green is reflected back making the leaf green in color. Please turn to page 233 of your books

11. Figure 9.6 page 233

12. Light-Independent Reactions The Calvin Cycle ▪Series of reactions that use carbon dioxide to form carbohydrates. ▪Does not require light. ▪Takes place in the chloroplasts. ▪Only one molecule of CO 2 is made each time through the cycle, it takes six times to make one glucose. Please turn to page 235

13. Page 235 The Calvin Cycle

14. Getting Energy to Make ATP Cellular Respiration ▪Three stages of Cellualar respiration: –Glycolysis (anaerobic) –Citric Acid Cycle (aerobic) –Electron Chain Transport (aerobic)

15. Fermentation Lactic acid and Alcoholic ▪Anaerobic energy process ▪Two ATP are formed ▪Lactic Acid is animals ▪Alcoholic in yeasts and plants Figure 9.12 page 241

16. Comparing Photosynthesis and Cellular Respiration Turn to page 243