CELLULAR RESPIRATION l Includes metabolic pathways l Begins with glucose and ends with carbon dioxide & water l Overall equation (aerobic) l Glucose-high energy molecule l Electrons are removed from substrates & received by oxygen (oxidation)

OVERALL DESCRIPTION l Glucose is oxidized and oxygen is released l Glucose is released slowly and ATP is produced gradually l Breakdown of glucose yields 38 ATP l Each reaction is catalyzed by l its own enzyme

COMPONENTS OF OVERALL PROCESS l Glycolysis l Transition Reaction l Kreb’s Cycle l Electron Transport

GLYCOLYSIS l Begins with the two phosphorylations using 2 ATP l Sugar cleavage occurs l Oxidations (dehydrogenations) occur l 2 ATP form. Aerobic or anaerobic respiration may follow

GLYCOLYSIS l Definition l 1. Gain of 2 ATP l 2. Occurs in the cytoplasm l 3. Does not require oxygen

AEROBIC RESPIRATION l The Transition Reaction l The Kreb’s Cycle l The Electron Transport System l Pyruvic Acid broken down into carbon dioxide and water l Takes place in the mitochondria

THE TRANSITION REACTION l Pyruvic acid is oxidized to Acetyl Co A and carbon dioxide is removed

THE KREB’S CYCLE l 1. Number of 0xidations (dehydrogenations) occur l 2. Carbon dioxide is produced l 3. 2 immediate ATP are produced per molecule of glucose. l The cycle turns twice for each glucose molecule.

THE ELECTRON TRANSPORT SYSTEM l 1. Series of carriers accepts electrons. Electrons are passed from carrier to carrier until received by oxygen. l Electrons pass from higher to lower energy state l Once formed ATP diffuses out of the mitochondria. l

ANAEROBIC RESPIRATION OR FERMENTATION l Pyruvic acid is a pivotal metabolite in cellular respiration l If oxygen is not available to the cell, fermentation, an anaerobic process occurs l Lactic acid or ethyl alcohol and l carbon dioxide is formed &2ATP

ENERGY YIELD FROM GLUCOSE METABOLISM AEROBIC 1. From Kreb’s Cycle 2. From Electron Transport 3. From Glycolysis ANAEROBIC 1. From Glycolysis COMPARE END PRODUCTS FOR BOTH PROCESSES

CRITICAL THINKING l Cyanide interrupts the cytochrome system of electron transport. l Why is cyanide a universal poison effective in all organisims with mitochondria?

CRITICAL THINKING l The electron transport system is the producer of ATP from ADP in aerobic respiration. Stopping the electron transport system stops ATP production. Which stops metabolic reactions. l This is a universal system.