This animation shows how the proton gradient across the mitochondrial membrane powers the ATP synthase enzyme to make ATP. It is the third 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.
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 film explores how life recovered after an asteroid wiped out the dinosaurs and how those events shaped the diversity of plants and mammals on Earth today.
This video case study explores the approaches scientists used to identify a mutation that causes retinitis pigmentosa (RP), a progressive disease that leads to blindness.
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.
This activity explores an image of tumor cells invading muscle tissue, which serves as a phenomenon for learning about cancer, mutations, and cell division.