1. Glycolysis and Cellular Respiration Go to Section:

2. 1. Organisms obtain energy from food 2. Glucose is main source of food for cells 3. Cells break chemical bonds of glucose; energy released 4. Energy is stored in ATP 5. Making ATP is part of cellular respiration Slide # 2 Go to Section: Cells Need Energy

3. Cellular Respiration produces carbon dioxide and water, which are used as starting materials (reactants) in photosynthesis C 6 H 12 O 6 + 6 O 2 6 CO 2 + 6 H 2 O + 36 ATP Reactants Products Enzymes Slide # 3 Cellular Respiration Equation

4. Glucose Glycolysis Krebs cycle Electron transport Fermentation (without oxygen) Alcohol or lactic acid Overview of Cellular Respiration Pathways Slide # 4 Go to Section:

5. Glycolysis: Breaking Sugar 1. Occurs in cytoplasm 2. Glucose (C 6 H 12 O 6 ) is broken down into 2 molecules of pyruvic acid (C 3 H 6 O 3 ) 3. Does not use oxygen (anaerobic) 4.Net gain of 2 ATP’s Slide # 5 An overview of the process of glycolysis. Glycolysis occurs in prokaryotes & eukaryotes 4 ATP produced — 2 ATP consumed 2 ATP net gain Also produces: 2 NADH 2 pyruvic acids

6. Cellular Respiration: The Krebs Cycle & Electron Transport Go to Section:

7. 1. Cellular respiration: process that releases energy by breaking the chemical bonds of glucose in the presence of oxygen. a.Aerobic b/c it uses oxygen b.Occurs in the mitochondria c.Occurs in eukaryotic cells such as: Slide # 7 Go to Section: Cellular Respiration

8. After Glycolysis: Cellular Respiration 1. About 90% of energy from glucose remains in pyruvic acid 2. Purpose of the Krebs cycle: a. Release the remaining energy & capture the highly energized electrons by NAD + & FAD (electron carriers) 3. Produces CO 2 as waste Slide # 8 cytoplasm

9. The Breakdown of Pyruvic Acid 1. Pyruvic acid diffuses into matrix of the mitochondria 2. Each pyruvic acid is converted into acetyl-CoA a. Produces 2 CO 2 b. Produces 2 NADH c. Transfers hydrogen atoms & highly energized electrons to NAD + & FAD Slide # 9

10. Results of the Krebs Cycle Break down of Acetyl-CoA yields: 1 Acetyl-CoA 2 Acetyl-CoA 1 ATP 2 ATP 3 CO 2 6 CO 2 4 NADH 8 NADH 1 FADH 2 2 FADH 2 ATP and CO 2 diffuse out of the mitochondria NADH and FADH2 move to the cristae Slide # 10

11. ETC: Oxidative Phosphorylation 1. Uses the H (carried by NADH & FADH 2 ) to build up a H + gradient in the inner membrane space to make 32 ATPs 2. Oxygen is consumed & water produced 3. ADP is phosphorylated (to ATP) in the presence of O 2 Inner Membrane Space Slide # 11

12. The Electron Transport Chain 1. The ETC is located on inner membrane of the mitochondria. (cristae) 2. Oxygen is final acceptor of electrons. 3. Produces 32 ATP’s. a. the most efficient form of ATP production Slide # 12 Proton Gradient builds up on one side of the membrane

13. The Electron Transport Chain 1. NADH & FADH 2 carry pairs of electrons (from glycolysis & Krebs cycle) to ETC. 2.As electrons are passed along ETC, the energy in the electrons is used to pump H + into inter membrane space. a. Creates a high concentration of H + in inter membrane space b. H atoms diffuse back into core of mitochondria through transport proteins (chemiosmosis) c. Transport proteins use flow of H atoms to bond last P onto ADP to create ATP (phosphorylation) Slide # 13

14. Fermentation: Anaerobic 1.Respiration that does not use O 2 2.Releases net gain of 2ATP’s 3.Most of the energy from glucose remains in the organic molecules (lactic acid or alcohol) produced from fermentation. Lactic Acid fermentation: a.Glucose is broken down into lactic acid b.Used to produce yogurt, buttermilk and sour cream c.Occurs in muscle cells during intense exercise d.Lactic acid causes muscle cells to BURN Alcoholic fermentation: (Occurs in Yeast) a.Glucose is broken down into alcohol & CO 2 b.CO 2 given off by yeast causes bread dough rise c.Process is also used to make biofuels out of crop residue My muscles are on fire!

15. Sequence these Oxidative phosphorylation Glycolysis Krebs cycle Slide # 15 312312