1. Bellringer 11/17 1. What is energy? 2. What do the following have in common? Reminders: HW #12, LAB FEE, Quiz #7 Next Wk!

2. Energy in the Cell Photosynthesis and Respiration

3. Energy Energy- the ability to do work Energy- the ability to do work The energy for living things is stored in chemical compounds The energy for living things is stored in chemical compounds 2 organelles are responsible for making those compounds for cells: 2 organelles are responsible for making those compounds for cells: Chloroplasts- through photosynthesis in plants Chloroplasts- through photosynthesis in plants Mitochondria- through cellular respiration in animals Mitochondria- through cellular respiration in animals

4. Where Does the Energy Come From? Energy is stored in food!!! Energy is stored in food!!! Plants use sunlight to make their food. Plants use sunlight to make their food. Plants are autotrophs—they make their own food. Plants are autotrophs—they make their own food. Animals and other organisms that cannot use the sun’s energy directly must consume food for energy. Animals and other organisms that cannot use the sun’s energy directly must consume food for energy. Animals are called heterotrophs—their food comes from different sources. Animals are called heterotrophs—their food comes from different sources.

5. Chemical Energy Energy in food is stored in chemical bonds Energy in food is stored in chemical bonds There are 3 main energy molecules that cells use: There are 3 main energy molecules that cells use: ATP (adenosine tri-phosphate) ATP (adenosine tri-phosphate) ADP (adenosine di-phosphate) ADP (adenosine di-phosphate) Glucose (C 6 H 12 O 6 )- carbohydrates Glucose (C 6 H 12 O 6 )- carbohydrates

6. ATP and ADP ATP is made of: ATP is made of: Adenine (a nitrogen compound) Adenine (a nitrogen compound) 5-carbon sugar 5-carbon sugar 3 phosphate groups 3 phosphate groups ADP is made of: ADP is made of: Adenine (a nitrogen compound) Adenine (a nitrogen compound) 5-carbon sugar 5-carbon sugar 2 phosphate groups 2 phosphate groups So what’s the only difference between the two? So what’s the only difference between the two? The Phosphate Groups! 2 vs. 3 The Phosphate Groups! 2 vs. 3

7. ATP vs. ADP ATP can become ADP by breaking a chemical bond and removing a phosphate group ATP can become ADP by breaking a chemical bond and removing a phosphate group When you break chemical bonds you RELEASE energy When you break chemical bonds you RELEASE energy The cell can store energy by ADDING a phosphate group to ADP to become ATP. The cell can store energy by ADDING a phosphate group to ADP to become ATP. ATP acts like a fully charged battery ATP acts like a fully charged battery

8. ATP vs. Glucose ATP is NOT good for storing large amounts of energy long-term. ATP is NOT good for storing large amounts of energy long-term. The cell uses glucose because it can store 90 times as much energy as ATP. The cell uses glucose because it can store 90 times as much energy as ATP.

9. Photosynthesis Photo: using light Photo: using light Synthesis: to put something together Synthesis: to put something together >>>The process in which cells use light energy to make carbohydrates (food) Reminder: takes place in chloroplasts Reminder: takes place in chloroplasts Chlorophyl- pigment that traps light energy needed for photosynthesis- LAB on this on Wednesday!!! Chlorophyl- pigment that traps light energy needed for photosynthesis- LAB on this on Wednesday!!!

10. Photosynthesis Summarized __ CO 2 + __ H 2 O + light energy = __C 6 H 12 O 6 + __ O 2 trapped by chlorophyl But, we need to balance this equation… So…. 6 CO 2 + 6 H 2 O + light energy = C 6 H 12 O 6 + 6 O 2 trapped by chlorophyl This process contains light-dependent (requires sunlight) and light-independent reactions (no light needed) This process contains light-dependent (requires sunlight) and light-independent reactions (no light needed) Can we guess which part is which? Can we guess which part is which?

11. Cellular Respiration The opposite of photosynthesis The opposite of photosynthesis Instead of making food, we now break down that food to release energy Instead of making food, we now break down that food to release energy Reminder: takes place in the mitochondria Reminder: takes place in the mitochondria C 6 H 12 O 6 + 6 O 2 = 6 CO 2 + 6 H 2 O + ATP (from plants) (for plants) (for our use)

12. Cellular Respiration Stages 3 Stages 3 Stages Glycolysis- takes place in the cytoplasm of the cell Glycolysis- takes place in the cytoplasm of the cell Citric Acid Cycle (Krebs Cycle)- in the mitochondria Citric Acid Cycle (Krebs Cycle)- in the mitochondria ETC (Electron Transport Chain)- in the inner membrane of the mitochondria ETC (Electron Transport Chain)- in the inner membrane of the mitochondria To remember: To remember: Glycolysis: anaerobic (no oxygen needed) Glycolysis: anaerobic (no oxygen needed) Citric Acid Cycle and ETC: aerobic (need oxygen to go) Citric Acid Cycle and ETC: aerobic (need oxygen to go) Total energy after Cellular Respiration: 38 ATP Total energy after Cellular Respiration: 38 ATP

13. Cellular Respiration

14. What happens w/o O? When the cell needs energy (when you exercise heavily or run long-distance), but little or no O is available for proper respiration, the cell will enter an anaerobic process called fermentation When the cell needs energy (when you exercise heavily or run long-distance), but little or no O is available for proper respiration, the cell will enter an anaerobic process called fermentation 2 kinds of Fermentation: 2 kinds of Fermentation: Lactic Acid- this is why muscles hurt Lactic Acid- this is why muscles hurt Alcoholic - used by yeast, bacteria, this is how we make beer, cheese, bread, vinegar, wine and cider Alcoholic - used by yeast, bacteria, this is how we make beer, cheese, bread, vinegar, wine and cider

15. Photosynthesis vs. Respiration

16. PhotosynthesisRespiration Food madeFood broken down Energy from sunlight stored in glucose Stored energy in glucose released CO 2 taken inCO 2 and H 2 O given off O 2 given offO 2 taken in Occurs in the presence of chlorophyll- plants only Occurs in all living organisms Light neededNo light needed In ChloroplastsIn Mitochondria