Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Sleep serves a multitude of functions for humans. These functions exist at multiple physiological levels, from cells (bottom panel) to bodily systems (left panel), through to multiple brain functions and systems (right panel).
