1 - 12 of 110 results
Citric Acid Cycle

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.

Electron Transport Chain

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.

ATP Synthesis

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.

Modeling the Structure of DNA

In this activity, students build a paper model of DNA and use their model to explore key structural features of the DNA double helix. This activity can be used to complement the short film The Double Helix.

White-Nose Syndrome in Bat Populations

This activity guides the analysis of a published scientific figure from a study that modeled the impact of an infectious fungal disease on a bat population.

Exploring Biomass Pyramids

This interactive module allows students to collect and analyze data from a virtual river to construct biomass and energy pyramids.

How Science Works

This interactive module allows students and educators to document, annotate, and reflect upon scientific research processes.

Tiktaalik Fossil: Pectoral Fin

This model shows the pectoral fin bones of Tiktaalik, a vertebrate that existed about 375 million years ago and had features of both fish and tetrapods (four-limbed animals).

Tiktaalik Fossil: Body

This model shows the skeleton of Tiktaalik, a vertebrate that existed about 375 million years ago and had features of both fish and tetrapods (four-limbed animals).

Tiktaalik Fossil: Humerus

This model shows the humerus bone of Tiktaalik, a vertebrate that existed about 375 million years ago and had features of both fish and tetrapods (four-limbed animals).