THE ELECTRON TRANSPORT CHAIN & CHEMIOSMOSIS

ETC creates a gradient across the cristae membrane, the gradient is then used to produce ATP through chemiosmosis or oxidative phophlorylation
almost all ATP produced during cellular respiration is produced by chemiosmosis

PART 1: A Proton Gradient

ETC produces a proton gradient
NAHD and FADH2 carry out high energy electrons from Krebs Cycle and glycolysis to the ETC, release energy that is used to pump protons (H+) across the cristae membrane which then created the proton gradient
gradient represents stored or potential energy that can be used to work just like water behind a dam can be used to produce electricity

PART 2: Chemiosmosis

uses the stored energy in the proton gradient to convert ADP to ATP and to power synthesis of ATP
actual mechanism by which ATP is produced
depends on molecule located within cristae membrane; ATP synthase which is actually a channel structure that spins
as protons enter the ATP synthase channel, part of the molecule turns and attaches to a phosphate molecule which then turns the once ADP into ATP
OXYGEN pulls electrons through ETC and also serves as the FINAL ELECTRON AND PROTON RECEPTOR IN ETC
when oxygen combines with protons and electrons at the end of ETC, water is a waste product, this is the water vapor we exhale
ETC collection of carrier molecules (cytochromes) embed in cristae membrane
every mitochondria has LOTTA ETCs (thousands)
ETC carries electrons through a series of redox reactions as special molecules bind to and let go of electrons, in a redox reaction one atom gains elections (reduction) while one atom loses electrons (oxidation)
water is produced as a waste product as oxygen combines with protons and electrons that flow dow the ETC
proteins cannot diffuse directly through the cristae membrane only through the ATP synthase channel

	Created by seylastar1999 almost 9 years ago

BIOLOGY Note on CELLULAR RESPIRATION NOTES, created by seylastar1999 on 23/05/2015.