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.
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 activity builds on information presented in the short film Genes as Medicine. Students interpret actual pedigrees to determine the inheritance pattern of Leber congenital amaurosis (LCA), an inherited form of blindness.
This activity builds on information presented in the video Selection for Tuskless Elephants. Students use scientific evidence and reasoning to construct an explanation of and develop an argument for tusklessness in elephant populations.
This interactive module allows students and educators to build models that explain how the Earth system works. The Click & Learn can be used to show how Earth is affected by human activities and natural phenomena.