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.
The two forms of DNA are cartooned here. B-DNA has a simple helical structure and is right-handed, leading to negative nodes. Z-DNA is a helix with a zigzag backbone resulting from a dimer being the helical repeat unit. It is left-handed, leading to positive nodes.
