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 extends concepts covered in the film Got Lactase? The Co-evolution of Genes and Culture. Students infer whether someone is likely to be lactase persistent or nonpersistent based on the data from two different tests.
In this activity, students simulate a lactose tolerance test, similar to the one shown in the short film The Making of the Fittest: Got Lactase? The Co-evolution of Genes and Culture, to determine which samples contain the lactase enzyme.