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 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 three-part animation series explores the biology of the virus SARS-CoV-2, which has caused a global pandemic of the disease COVID-19.

The added information provided at pause points within the animation Coral Bleaching allows for a richer exploration of coral reefs, symbiosis, and other topics in biology.

In this activity, students learn about the factors that regulate the population sizes of wildebeest and buffalo in Serengeti National Park.

In this activity, students evaluate a science news article to determine whether it is a trustworthy source of information.

In this activity, students find a scientist with whom they can relate in some way and then explore and reflect upon the impact of that scientist’s work.

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 activity explores content presented in the animated video Solving Crimes with the Necrobiome, which describes the microbial changes associated with decomposing corpses.

This activity allows students to formulate and analyze scientific questions.

In this video, ecologist Tony Sinclair takes us through the steps of how he uncovered that the eradication of an infectious disease in cattle led to a boom in the Serengeti’s buffalo and wildebeest numbers.