This animation shows the reactions of the citric acid cycle, which splits off carbon atoms and generates energy-rich reduced forms of cofactor molecules. It is the first of three animations about cellular respiration.
This animation shows how the enzyme complexes of the electron transport chain harvest energy from cofactor molecules to pump protons across the mitochondrial membrane and establish a chemical gradient. It is the second of three animations about cellular respiration.
Across the U.S. and in Europe, researchers and health officials say they can track the course of a community outbreak of the new coronavirus by studying the waste flushed from its bathrooms. And that can provide a valuable addition to public health tools, they say.
Testing is critical to controlling the coronavirus and eventually easing restrictions that have halted daily life for most Americans. But there’s been confusion about what kinds of tests are available and what they actually measure.