Ask the Chatbot Games & Quizzes History & Society Science & Tech Biographies Animals & Nature Geography & Travel Arts & Culture ProCon Money Videos
respiratory chain
References
Images
Diagram of the respiratory chain in metabolism, showing the flow of electrons from NADH and FADH2 through complexes and cytochromes, ending with the reduction of oxygen to water. Key molecules, sites, and electron transfers are labeled.
Britannica AI Icon

respiratory chain

biochemistry
Also known as: electron transfer chain, electron transfer system(Show More)
Written by
The Information Architects of Encyclopaedia Britannica

The Information Architects maintain a master list of the topics included in the corpus of  Encyclopædia Britannica, and create and manage the relationships between them.
The Information Architects of Encyclopaedia Britannica
Last updated

Quick Summary

Diagram of the respiratory chain in metabolism, showing the flow of electrons from NADH and FADH2 through complexes and cytochromes, ending with the reduction of oxygen to water. Key molecules, sites, and electron transfers are labeled.
The respiratory chain Four types of hydrogen or electron carriers are known to participate in the respiratory chain, in which they serve to transfer two reducing equivalents from reduced substrate to molecular oxygen.

The respiratory chain, also known as the electron-transport chain, is a crucial part of cellular respiration that occurs within the mitochondria of eukaryotic cells. This process is responsible for generating the majority of the cell's energy currency, adenosine triphosphate (ATP), through a series of controlled oxidation-reduction reactions.1234

Essentially, electrons are passed along a chain of protein complexes embedded in the inner mitochondrial membrane. As electrons move down this chain, energy is released and used to pump protons across the membrane, creating an electrochemical gradient. This gradient then drives the synthesis of ATP as protons flow back across the membrane through a special enzyme complex called ATP synthetase. The final electron acceptor in this chain is oxygen, which combines with protons to form water. This entire process is known as oxidative phosphorylation.1523

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
6 Britannica Sources
  1. cell - The electron-transport chain
  2. oxidative phosphorylation
  3. cellular respiration
  4. metabolism - ATP synthesis in mitochondria
  5. metabolism - The nature of the respiratory chain
  6. tricarboxylic acid cycle

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.