The fifth MWM Energy Metabolism lesson explores the third and fourth steps of the citric acid cycle and explains how the rate of ATP production is regulated according to the cell’s need for ATP. Together with lesson four, it explains how cells regulate their ATP production according to their needs and abilities. In the course of exploring this theme, we look at the role of AMP kinase (AMPK) in promoting energy uptake when ATP levels are low. Watch the full lesson at chrismasterjohnphd.com/mwm/2/5 Sign up for MWM Pro for early access to content, enhanced keyword searching, self-pacing tools, downloadable audio and transcripts, a rich array of hyperlinked further reading suggestions, and a community with a forum for each lesson.