Cellular Respiration Chapter 7

Cellular Respiration Glycolysis and Fermentation Aerobic Respiration

Photosynthesis vs. Cellular Respiration

Cellular Respiration Overview Overall Reaction*: Overall Reaction C 6 H 12 O 6 +6O 2  6CO 2 +6H 2 O+Energy (ATP)) Aerobic Path (O 2 ), 2 Steps: net 36 ATP 1. Glycolysis* Glycolysis 2. Aerobic Respiration Anaerobic Path (no O 2 ), 2 Steps: net 2 ATP Not efficient 1. Glycolysis 2. Fermentation: Lactic Acid or Alcoholic

Cellular Respiration Cellular Respiration *Overview Series of redox reactions

Cellular Respiration vs. Fermentation

Glycolysis* Location: cytosol Products: 1. 2 Pyruvic Acids (3-C) 2. 2 NADH (e- acceptors) 3. 4 ATP – 2 ATP used = 2 ATP net

Fermentation: Without O 2 Lactic Acid Location: cytosol Products: 1. Regenerates NAD + 2. Lactic Acid Uses: 1. Food production: cheese & yogurt 2. Muscle cells (i.e. sprint) Alcoholic Location: cytosol Products: 1. Regenerate NAD + 2. Ethyl Alcohol 3. CO 2 Yeast & some plant cells Uses: 1. Wine & beer 2. Bread making

Lactic Acid Fermentation Cheese, yogurt, diary products Muscle cells

Alcoholic Fermentation Yeast – wine, beer, bread

Summary of Fermentation

Aerobic Respiration (O 2 ) Overview 2 Steps: 1. Krebs Cycle (KC) 2. Electron transport chain (ETC) Location: Prokaryotes: KC & ETC in cytosol Eukaryotes: KC: mitochondrial matrix ETC: inner mitochondrial membrane Products: KC: 6NADH, 2FADH 2, 2ATP, 4CO 2 ETC: 34 ATP

Mitochondria Krebs Cycle = mitochondrial matrix Electron Transport Chain = cristae

Krebs cycleKrebs cycle* Krebs Animation (con)Animation (con) Before the cycle begins: Pyruvic Acid (3 C) enters matrix Converted to Acetyl CoA (2 C), CO 2 given off, NADH created One glucose molecule = 2 acetyl CoA molecules= 2 turns of Krebs cycle = 6 NADH, 2 FADH 2, 2 ATP, and 4 CO 2

Krebs Cycle * Krebs Cycle

Electron Transport Chain Electron Transport Chain * ETC animation *( Con) ETC animation *( Con) NADH & FADH 2 donate electrons in high energy states The movement of electrons pumps H + out of matrix Concentration gradient is formed ATP Synthase acts as channel for H + into matrix ATP is created - Chemiosmosis O 2 accepts H + protons and e -, forming H 2 O

Electron Transport Chain * Electron Transport Chain * Chemiosmosis (cont.)

Cellular Respiration Energy Yield

Cellular Respiration Summary video