Chemical Reactions

1. Chemical Reactions Objectives 1-2

2. atoms bonds energy A chemical reaction is the process of rearranging ___________ to create new compounds by breaking and forming chemical _________. During chemical reactions __________ is either stored or released. A chemical equation uses symbols to show what occurs during a ________________. It can be thought of as the “recipe” for a compound. Example: 2H2 + O2 2H2O chemical reaction

3. Example: 2H2 + O2 2H2O • Reactants – substances used in the reaction; located on the left side of the equation. • Products – substances produced in the reaction; located on the right side of the equation. • What are the reactants in this equation? • What are the products in this reaction? H2 O2 H2 O

4. Example: 2H2 + O2 2H2O 2 If we wanted to make 4 molecules of H2O, how many O2 would we need?__________ If we used 8 molecules of O2, how many molecules of H2O would we make?_______ 16

5. Fe + CuCl2 FeCl2 + Cu FeCl2 Cu What are the products in this equation? What are the reactants in this equation? Fe CuCl2

6. Chemical reactions must obey the Law of Conservation of Mass. The Law of Conservation of Mass states that mass cannot be created or destroyed. What does this mean for chemical reactions? The reaction must start and end with the Same # of atoms and type of atoms

7. All chemical equations must obey the law of conservation of mass. When an equation obeys the law of conservation of mass we say the equation is BALANCED (these represent reactions that can happen). When an equation does NOT obey the law of conservation of mass we say it is UNBALANCED (an unbalanced equation represents something that will never happen).

8. Examples: 2H2 + O2 2H2O Reactants: H = 4 Product: H = 4 How many atoms of hydrogen are in the reactants? Product? How many atoms of oxygen are in the reactants? Products? Is this equation balanced? ___________ Why or why not? Reactants: O = 2 Product: O = 2 Yes The number of atoms on both side are equal

9. Examples: H2 + O2 H2O • How many atoms of hydrogen are in the reactants? Product? • How many atoms of oxygen are in the reactants? Products? • Is this equation balanced? ___________ Why or why not? Reactants: H = 2 Product: H = 2 How Reactants: O = 2 Product: O = 1 No The number of atoms on both side are NOT equal

10. Energy in Living Things Objectives 3-5

11. What is Energy? What do living things use energy for? The ability to do work; measured in joules or calories • Move • Digest • Pump • Make proteins • Transport molecules

12. Cells get most of their energy from _______. Cells must be able to _______ this energy. Why? Food Store Law of Conservation of Energy - A food source might not be available when energy is needed. • Energy cannot be created or destroyed; it can change forms • Living things must be able to covert energy from one form to another.

13. Four forms of energy Important to Life chemical bonds Macromolecules – energy is stored in the _________ ________ of macromolecules. Carbohydrates (Sugars) Lipids (Fats) Proteins

14. C, H, O – primary energy source – 4 cal/g C, H, O – stored form of energy – 9 cal/g C, H, O, N – 4 cal/g Carbohydrates (Sugars)– Lipids (Fats) – Proteins – Bond between C & H have a lot of energy. It can be released by breaking bonds

15. Four forms of energy Important to Life wave photons plants photosynthesis (energy from light is stored in sugars) 2. Light – a ________ that has energy in the form of _________; this form is energy is used by __________ during _________________.

16. Four forms of energy Important to Life 3 Phosphates 3. ATP – Adenosine Triphosphate – the primary source of energy used by cells. adenosine

17. energy When the last phosphate is removed, ___________ is released. + ℗ + Energy ADP + Phosphate ATP

18. Where does the energy in ATP come from? Food/light ADP + ℗ + Energy ATP Energy from __________ is stored in chemical bonds in ATP.

19. Four forms of energy Important to Life Compound 4. Electrons – Electrons (and their energy can be moved from one _________ to another. Electron Carriers – special compounds that easily gain and lose electrons and can transfer energy from one place to another. Examples: NADP+ + ē NADPH (empty) (full) H = + + ē

20. Enzymes Objectives 6-8

21. Enzymes - A protein that acts as a catalyst (speeds up chemical reactions) So reactions happen fast enough to sustain life functions • Why are enzymes needed? • How do enzymes work? • Enzymes lower the activation energy of a chemical reaction. ActivationEnergy is the energy needed to ______ a chemical reaction. start

22. No enzyme Start With enzyme Finish

23. shape protein Substance that the enzyme acts on Each enzyme has a specific ________ based on how the ________ is folded. Substrate – Each enzyme binds only to certain substrates. In order for the substrate to bind to the enzyme it must be the right ________. The place where the substrate binds to the enzyme is called the _______ ______ Once the enzyme and substrate bind, a reaction occurs. shape active site

24. Draw a picture explaining how an enzyme works in the space below. Active site -substrate products ENZYME

25. Example: The reaction shown below helps convert CO2 into a form that is more easily carried through the bloodstream. Without enzymes this reaction wouldn’t happen fast enough and dangerous levels of CO2 would build up in the bloodstream. The enzyme carbonic anhydrase allows this reaction to happen 10 million times faster. CO2 + H2O H2CO3 Video ENZYME

26. A substance other than the substrate blocks the active site Inhibitor • Controlling Enzymes • Enzymes don’t always need to be “ON.” There are 2 ways to turn an enzyme “OFF.” • Competitive Inhibition – • Non- Competitive Inhibition – Substrate A molecule binds to a location other than the active site and changes the shape of the enzyme Substrate V ideo Inhibitor

27. Overview of Photosynthesis Objective 9, 10, 12, 13

28. Photosynthesis – the process in which plants use energy of ________ to convert ______ and ______ _______ into high-energy ________ and _________ a waste product. sunlight water carbon dioxide oxygen Sugars (glucose) Equation: 6CO2 +12H2O C6H12O6 + 602 + 6H2O CO2 – carbon dioxide C6H12O6 – glucose (carb)H2O – Water (soil) O2 – Oxygen H2O - Water Waste products • Purpose: To store energy from light in glucose

29. carbon oxygen hydrogen Simple sugar (Glucose) quick energy • Monosaccharide – • Polysaccharide - A side note: structure of carbohydrates – carbohydrates are molecules made of _______, _________, and ________. Complex sugar made of many simple sugar (ex. Starch)

30. Location: Photosynthesis takes place in the ___________ of plants cell Chloroplasts Stack of thylakoids Background material of chloroplasts • Grana – • Stroma – • Thylakoid – • Chlorophyll – • Pigment- light absorbing molecules Disk Containing chlorophyll Green, light absorbing pigments

31. Structures of Photosynthesis =Nucleus =Cell Wall Plant Cell

32. Plant Cell Chloroplast Grana Thylakoid

33. Grana Chlorophyll Thylakoid

34. Details of Photosynthesis Objectives 14, 16

35. Equation:6CO2 +12H2O C6H12O6 + 602 + 6H2O To store energy from sunlight in glucose Purpose:

36. Remember: Photosynthesis has 2 main stages light H2O O2 ATP NADPH Light Dependent Reactions use _________ and ________. Energy is temporarily stored in _______ and _________. ________ is given off as a waste product. Light Independent Reactions (Calvin Cycle) uses _______ to convert the energy from _______ and _________ into ________. ________is given off as a waste product. CO2 ATP NADPH Glucose H2O

37. *add equation and thylakoid and stroma H2O CO2 Light NADP+ ADP +P Calvin Cycle Thylakoid Stroma ATP NADPH Chloroplast O2 SUGARS 6CO2 +12H2O C6H12O6 + 6O2+ 6H2O

38. Photosynthesis (light dependent) Location: Thylakoid of Chloroplast Materials Needed: Light, H2O, ADP, NADP+ Final Products: O2, H+, ATP, NADPH

39. Stage 1: Light Dependent Reactions: Capturing The sun’s energy Energy from light strikes a chlorophyll molecule in the membrane of the thylakoid. This light energy excites an _electron_ and it passes through a chain of molecule called the electron transport chain. As it moves it losesenergy. Water in the plant is broken into,H+,_O and _electrons_. The electrons replace the one lost from chlorophyll The O combine to form O2 and leave as a waste product. The movement of electrons causes more H+ to move into the thylakoid.

40. 5. Light strikes a 2nd chlorophyll molecule and the Electron is reenergized . This high-energy electron is picked up by NADP+ (an electron carrier) to form NADPH. 6. As this happens over and over again protons (H+) build up in the thylakoid. They can only get across the membrane by going through a protein_ The energy from the H+ moving through the channel converts ADP to ATP.

41. Stage 2: The Calvin Cycle – Making Glucose Stroma of chloroplasts ATP, NADPH, H+, CO2 Glucose, H2O Location: Materials needed: Final products: Main Idea: Energy stored in ____ and _____ from the light reaction is used in the Calvin cycle to convert ________ ________ into high-energy sugars (Glucose). ATP NADPH Dioxide Carbon

42. Intro to Respiration Objectives 9, 12-15

43. Cellular Respiration (Obj. 9a) Food Molecules Energy Energy ATP The process by which _______________ are burned in the cell in order to produce __________. Purpose: to store ________ from food in _____ so cells can carry out life processes Remember: for cells to function they need energy; the main form of energy used by cells is ____. The equation : ATP C6H12O6 + 6O2 6CO2 + 6H2O + 36 ATP

44. Cellular Respiration Energy Plants Glucose – Made by plants in photosynthesis; has LOTS of ______, but it is not in a usable form. Oxygen – produced by _______ during photosynthesis ATP – the main source of ________ used by all Living things Water – released into the air as waste Location: Energy Cytoplasm Mitochondria

45. Comparing Photosynthesis and Cellular Respiration To make Glucose Burn glucose for energy Chloroplasts Mitochondria/Cytoplasm Plants, Bacteria, Protists (Autotrophs) All living things CO2 +H2O C6H12O6 + O2 C6H12O6 + O2 + H2O CO2 + H2O + ATP 6CO2 + 6H2O Light C6H12O6+ 6O2+ H2O C6H12O6 + 6O2 6CO2 + 6H2O + 36ATP

46. ATP ATP food more energy As _____ is used up it must be replaced. The energy to build more ____ comes from _____. It takes some energy to break down food molecules, BUT cells get ____________ from the food that they use to break it down. What is the major source of energy for organisms? Where does it come from? Food (Glucose) Plants (photosynthesis)

47. Details of Respiration Objective 14, 18

48. Respiration C6H12O6 + 6O2 6CO2 + 6H2O + 36 ATP To get energy from glucose and store it in ATP Equation: Purpose: Summary of Energy Flow: Energy from _______ is transferred to electron carriers and then to ____. Glucose ATP

49. Who’s Who in Respiration Glucose – one of the most basic carbohydrates; starting material for respiration ATP – main energy source used by the cell NAD+/NADPH+H - an electron carrier FAD/FADH2 – another electron carrier The first step of all forms of respiration is ________. After that if no oxygen is present the cell goes through fermentation. If oxygen is present the cell proceeds to cellular respiration. Glycolysis

50. The steps of cellular respiration are: The Krebs Cycle and Electron Transport Electrons carried in NADH 6O2 Electrons carried in NADH and FADH2 1 3 Glucose 2 Electron Transport Chain Krebs Cycle Glycolysis Pyruvic Acid Mitochondrion Cytoplasm 32 ATP +6H2O 2ATP 2ATP + 6CO2