The Encyclopedia of Life aims to increase awareness and understanding of living nature by gathering, generating and sharing knowledge in an open, freely accessible and trusted digital resource.
Choose the human system you want (skeletal, nervous, digestive, etc.). Then click on the highlights to get detailed information. Too many ads but useful info.
Interesting site on the human brain, including its structure. This part of a series of sections. Also has other brain-related topics, especially relating to artificial intelligence.
Nice photos of the human skeleton. You can also see videos and additional info on each bone by using the menu on the detail photos. From the University of Texas. You can also see skeletons of other primates.