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3 Tutorials that teach Krebs Cycle
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Krebs Cycle

Krebs Cycle

Author: Nathan Lampson

This lesson will introduce the Kreb's cycle and explain how it is used to convert pyruvic acid into carbon dioxide.

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The Krebs cycle, also known as the citric acid cycle, is a phase of cellular respiration that takes place inside the mitochondria of a cell.


During the citric acid cycle, hydrogen atoms and electrons are provided so that the electron transport chain can occur.  The citric acid cycle and the electron transport chain both play an important role in using ATP molecules as energy in living things.


Molecules used during the citric acid cycle are pyruvate produced during glycolysis in the form of acetic acid, ADP, phosphate, NAD+, and FAD molecules.


The citric acid cycle produces CO2 and ATP, as well as electrons and hydrogen atoms bonded to NADH and FADH2 molecules.

Krebs Cycle