Biology Study Guide TopicsEndocrine System | Lymphatic System | Blood | Circulatory System | Skull Bones | Human Skull and Brain | Tissue Types | The Cell | DNA | Anatomy Models | Electron Transport Chain | History of Microbiology | Human Anatomy | Punnett Squares | What is Mitosis | What is Life | Macromolecules | Cellular Respiration | DNA Replication | Enzymes | Pathogenic Bacteria | Natural Selection | Punnett Squares | Transcription and Translation | Exam Notes | Viruses | Osmosis | Protists | Genetic Code | Mendelian Genetics | Meiosis | Sensory Processing | Amino Acids |
Online PresentationsBones of the Human Skull | Tissue Types | Selective and Differential Media
Classroom ActivitiesRecombinant DNA Cut And Tape Classroom Activity
The Electron Transport Chain
1) The electron transport chain is used to generate ATP (energy) in most organisms- both prokarytoic and eukaryotic.
2) NADH and FADH2 generated from glycolysis, pyruvate oxidation and the citric acid cycle are used to pump protons across a phospholipid bi-layer membrane
3) In eukaryotes the protons are pumped across the inner membrane of the mitochondria, in prokaryotes (bacteria) the protons are pumped across the cell membrane
4) This accumulation of a concentration gradient of charged protons on one side of a membrane is a great store of potential energy and is referred to as the proton motive force.
5) Protons are pumped as electrons are donated from NADH and FADH2 to proteins that are embedded in the membrane. These electrons pass through a series of proteins- thus the name: electron transport chain.
6) The electrons ultimately combine with O2 and protons to make water. Oxygen (O2) is the final electron acceptor.
7) ATP is generated chemiosmotically as the protons move back down the concentration gradient through ATP Synthase which then phosporylates ADP to ATP.
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