A comprehensive resource of physical constants and properties.

Naming convention information and guidance from the International Union of Pure and Applied Chemistry (IUPAC).

Collection of enzyme functional data classified according to the Enzyme Commission list of enzymes.

A database of detailed and comprehensive descriptions of the relationships of known protein structures.

From the DNA Learning Center, these animations feature visualizations of cellular and molecular processes. Videos have transcripts.

3d visualizations of molecules and minerals. Designed for instruction, and the 3d models can be rotated.

Compendium of annotative information about human genes, run by the Weizmann Institute of Science.

A community driven collection of biological parts to build synthetic biology devices and systems. Run by the International Genetically Engineered Machine (iGEM) Foundation.

A source of property data on many organic compounds and a few common inorganic compounds. Maintained by the US Department of Commerce.

A free resource maintained by the Royal Society of Chemistry that contains property and spectra information.

A quick look up for CAS Registry numbers for approximately 7,900 common chemicals of public interest.

Search for structures, substances, and bioassay records; part of PubMed

Images and animations of cells from a variety of organisms.