The spine is an amazing piece of architecture that is often neglected until we get a backache. Learn more about the spine in this video from Discovery Health's "Body Invaders."
WHAT'S INSIDE: HUMAN BODY
- Body Parts
- Body Systems
The lymph system is the body's drainage system. It is composed of a network of vessels and small structures called lymph nodes. Learn more about the workings of this crucial system.
At night, your eyes adjust to darkness after several minutes. Do you know why it takes that long? Take a look at how your eyes adjust to darkness.