2/12 Daily Catalyst Pg. 82 Fermentation 1. Where do the hydrogens come from in the ETC? 2. Where do the hydrogens go after they are delivered to the ETC? 3. Described chemiosmosis.

2/12 Class Business Quiz #20 mini-test TOMORROW All of Cellular respiration AND fermentation Mardi Gras review pages: Workbook pages: 35, 37-43, 109, and 69 Review cellular respiration Quiz #20 corrections Log your study hours!

2/12 Class Business Just a reminder: NO HOODS No even tucked in. This is your last warning then they are mine No hats in the building. Even if you take it off in the class. No headphones, even hanging out of your shirt! This is your last warning then they are mine! ID’s and tucked in shirts at all times! Clear back backs and purses must be small! Tardies- NO MORE! We will move to more of drastic measure

2/12 Class Business Seniors: Juniors AND Seniors Scholarship opportunities available! Pell Grants Delgado will be on campus (2/25) Juniors AND Seniors ACT on March 17th You should be studying! 18+ (cords) EOC rewards for goods and excellent: CiCi’s pizza

2/12 Agenda Daily Catalyst Class Business Review Fermentation notes Book work Homework: Study for quiz and finish book work

Electron transport chain Oxidative phosphorylation Chemiosmosis and the electron transport chain Oxidative phosphorylation. electron transport and chemiosmosis Glycolysis ATP Inner Mitochondrial membrane H+ P i Protein complex of electron carners Cyt c I II III IV (Carrying electrons from, food) NADH+ FADH2 NAD+ FAD+ 2 H+ + 1/2 O2 H2O ADP + Electron transport chain Electron transport and pumping of protons (H+), which create an H+ gradient across the membrane Chemiosmosis ATP synthesis powered by the flow Of H+ back across the membrane synthase Q Oxidative phosphorylation Intermembrane space mitochondrial matrix Figure 9.15

There are three main processes in this metabolic enterprise Electron shuttles span membrane CYTOSOL 2 NADH 2 FADH2 6 NADH Glycolysis Glucose 2 Pyruvate Acetyl CoA Citric acid cycle Oxidative phosphorylation: electron transport and chemiosmosis MITOCHONDRION by substrate-level phosphorylation by oxidative phosphorylation, depending on which shuttle transports electrons from NADH in cytosol Maximum per glucose: About 36 or 38 ATP + 2 ATP + about 32 or 34 ATP or Figure 9.16

Concept 9.5: Fermentation enables some cells to produce ATP without the use of oxygen Key Point #1: Cellular respiration Relies on oxygen to produce ATP Aerobic respiration (O2) What if there is not ANY oxygen? Anaerobic respiration (no O2)

Key Point #2: Glycolysis Can produce ATP with or without oxygen How is ATP produced? Substrate Phosphorylation Who is the oxidizing agent of glycolysis? NAD+

Types of Fermentation Key Point #3: If NAD+ is consistently resupplied, Glycolysis can continue making the 2 ATP molecules. Fermentation

Key Point #4: Alcohol fermentation Pyruvate is converted to ethanol Bacteria and fungi (yeast) Bread, wine, and alcohol releases CO2 and oxidizes NADH back to NAD+

Key Point #5: Lactic acid fermentation: Pyruvate is reduced to form Lactate (lactic acid) as a waste product NADHNAD+ No CO2 is released Bacteria and Fungi Yogurt and cheese

Lactic Acid Fermentation During strenuous exercise, the blood cannot supply oxygen fast enough to the muscles. The lactic acid build up is what causes the fatigue and burning. When the oxygen supply has caught up, the lactic acid is converted back to pyruvate in the liver. So COOL!

(a) Alcohol fermentation (b) Lactic acid fermentation 2 ADP + 2 P1 2 ATP Glycolysis Glucose 2 NAD+ 2 NADH 2 Pyruvate 2 Acetaldehyde 2 Ethanol (a) Alcohol fermentation 2 Lactate (b) Lactic acid fermentation H OH CH3 C O – O O– CO2 2 Figure 9.17

Fermentation and Cellular Respiration Compared Both fermentation and cellular respiration Use glycolysis to oxidize glucose and other organic fuels to pyruvate Key player is NAD+ as the oxidizing agent We see differences in WHO the final electron acceptor is: CR: Oxygen Fermentation: Lactic acid or ethanol

Key Point #6: At the end of day, cellular respiration is all about producing ATP! Produces more ATP (~36 molecules) Fermentation: Only 2 molecules of ATP

Pyruvate is a key juncture in catabolism Glucose CYTOSOL Pyruvate No O2 present Fermentation O2 present Cellular respiration Ethanol or lactate Acetyl CoA MITOCHONDRION Citric acid cycle Figure 9.18

The Evolutionary Significance of Glycolysis Occurs in nearly all organisms Probably evolved in ancient prokaryotes before there was oxygen in the atmosphere

Concept 9.6: Glycolysis and the citric acid cycle connect to many other metabolic pathways

The Versatility of Catabolism Catabolic pathways Funnel electrons from many kinds of organic molecules into cellular respiration

The catabolism of various molecules from food Amino acids Sugars Glycerol Fatty Glycolysis Glucose Glyceraldehyde-3- P Pyruvate Acetyl CoA NH3 Citric acid cycle Oxidative phosphorylation Fats Proteins Carbohydrates Figure 9.19

Biosynthesis (Anabolic Pathways) Key Point #7: The body Uses small molecules to build other substances These small molecules May come directly from food or through glycolysis or the citric acid cycle

Regulation of Cellular Respiration via Feedback Mechanisms Is controlled by allosteric enzymes at key points in glycolysis and the citric acid cycle

Fructose-1,6-bisphosphate The control of cellular respiration Glucose Glycolysis Fructose-6-phosphate Phosphofructokinase Fructose-1,6-bisphosphate Inhibits Pyruvate ATP Acetyl CoA Citric acid cycle Citrate Oxidative phosphorylation Stimulates AMP + – Figure 9.20

9.6 Regulation of cellular respiration via feedback mechanisms How does CR use feedback inhibition? What is the enzyme that is controlled in glycolysis? What do we call this type of control? What molecule inhibits the enzyme? Stimulates?