This tour introduces the Big Bang cosmology, providing a brief overview of the essential elements of this theory and examining the gaps in the current hypothesis. Through this link to a research briefing on cosmology by the US National Academy of Sciences, you will find extensive information on present status of the issue.
Here is a quick-reference guide to the body's muscles, which certainly interest any medical science student. The link is searchable by body region. Each entry comes complete with a simple illustration, with brief notes about the muscle's function and nerve supply.
This site highlights a march of science development over the years. With documentation of everything from alchemy to mechanical television and galvanism, it provides coverage of unusual science and engineering topics, projects, and a scanned vintage science books. It also has humour articles and amateur science experiments from 1850.
Cell alive! provides plenty of information and interactive demonstrations of various animal and plant cells and cellular organisms. Biology students young and old will find it very useful as reference for medical research. Its huge video library gives a range of subjects including live recording and computer animation.