Cellular Respiration

Cellular RespirationThe process that releases energy from food in the

presence of oxygen

Aerobic v. AnaerobicOxygen is required at the very end of respiration in the

electron transport chain. Cellular processes that require oxygen are aerobic

Processes that do NOT require oxygen are considered anaerobic

The three stages of Cellular respiration are: 1. Glycolysis, 2. The Krebs Cycle, and 3. Electron

Transport & ATP Synthesis

Glycolysis1 molecule of glucose (a 6 carbon compound) is

transformed into 2 molecules of pyruvic acid (a 3 carbon compound)

ATP Production2 ATP molecules used to “get things going”

4 ATP molecules produced = gain of 2 ATP molecules

NADH ProductionNAD+ accepts 2 electrons =the 2NADH and holds them until they can be

transferred to electron chain

Glycolysis does NOT require oxygenHappens in the CYTOPLASM of the cell

The Krebs Cycle Pyruvic Acid is broken down into carbon dioxide in a

series of energy extracting reactions (AEROBIC)

Happens in the MATRIX of the Mitochondria

FOR EACH PYRUVIC ACID Molecule (there are 2)

Citric acid is broken down is a series of reactions 3 molecules of carbon dioxide

1 ATP, 4 NADH & 1 FADH2 (go to electron transport chain)

Electron Transport Chain & ATP Synthesis Uses high energy electrons from glycolysis and the Krebs

cycle to convert ADP to ATP

Electron Transport• NADH and FADH2 pass their high energy electrons to the electron transport

chain (electron carriers located in the inner membrane of mitochondria)• At the end of the chain an enzyme combines electrons with hydrogen ions

and oxygen to form water• Oxygen is the final electron acceptor and the chain can’t function without it• Forms a proton gradient used is ATP production (H+ from the NADH and

FADH2)

ATP Production• ATP synthase located in the inner membrane wall• ADP molecules are turned into ATP molecules

Together Glycolysis, the

Krebs Cycle, and the Electron

Transport chain results in about 36

molecules of ATP per 1

molecule of glucose.

https://www.youtube.com/watch?v=-Gb2EzF_XqA

Stage Where does it happen

Inputs Outputs

Glycolysis

Krebs Cycle

Electron Transport Chain & ATP synthase