ODWS icon

The Open Door Web Site
HOMEPAGE BIOLOGY HOMEPAGE CHEMISTRY PHYSICS ELECTRONICS HISTORY HISTORY OF SCI & TECH MATH STUDIES LEARNING FRENCH STUDY GUIDE  PHOTO GALLERY
IB BIOLOGY HOMEPAGE SCIENTIFIC INVESTIGATIONS DRAWING IN BIOLOGY DRAWING TABLES ERROR ANALYSIS IN BIOLOGY ALL ABOUT GRAPHS ICT IN BIOLOGY STATISTICS SCIENTIFIC POSTERS MOLECULAR IMAGES
WS

Powerpoint Presentation: Respiration and the Electron Transport Chain

Respiration Index

Introduction : Energy in Food
Glycolysis
Kreb's Cycle
Anaerobic Respiration
Photosynthesis and Respiration
The Respiratory Quotient and Respirometers

Topic Chapters Index

 

RESPIRATION

Custom Search

The Electron Transport Chain (ETC)

  • Most ATP is manufactured by oxidative phosphorylation.
  • A series of redox reactions using electron acceptor/donor molecules coupled to glycolysis and the Kreb's cycle.
  • The electron acceptors/donors reduce (when receiving electrons) and oxidise (when losing electrons) one another along an electrochemical gradient. Each molecule in the series has a lower redox potential than the one before.
  • Each redox reaction results in a release of energy.
  • If this energy release is > 30.5 kJ mol-1 a mole of ATP can be synthesised from ADP by a coupled reaction.
  • The first molecule in the series is NAD (or FAD), a coenzyme of various dehydrogenase enzymes.

    NAD (oxidised) double arrow NADH + H+ (reduced)

  • Next come a series of iron containing proteins called cytochromes
  • The last electron acceptor in the series is oxygen.
  • Electrons are produced by splitting hydrogen atoms taken from the food molecules (HArrow right H+ + e-) by dehydrogenases. Thus at the end of the ETC:

2H+ + 2e- + ½O2 Arrow right H2O

 

The location of the ETC

The mitochondrial inner membrane of eukaryotes(the plasma membrane of prokaryotes).

Surface area increased by cristae. Density of cristae is proportional to activity of the cell. For example:

Liver cell 40 m2 g-1 mitochondria

Heart muscle 200 to 250 m2 g-1 mitochondria

 

The Mechanism: The Chemiosmotic Pump

The ETC creates a concentration gradient by pumping H+ out of the mitochondrial inner matrix. As these H+ diffuse back into the matrix across the inner membrane they drive ATP synthesis.

.

The Open Door Web Site is non-profit making. Your donations help towards the cost of maintaining this free service on-line.

Donate to the Open Door Web Site using PayPal

SITE MAP
WHAT'S NEW?
ABOUT

PRIVACY

COPYRIGHT

SPONSORSHIP

DONATIONS

ADVERTISING

© Paul Billiet 2018
Any questions or problems regarding this site should be addressed to the webmaster

Hosted By
Web Hosting by HostCentric


SiteLock