Photo: Coming Soon: Your Personal DNA Map?



The chemical DNA (deoxyribonucleic acid) includes the instructions for all cells, the basic working units of every living thing. Twisted double strands of DNA are joined together by linked pairs of bases (A, T, C, and G) like the rungs of a ladder.

Specific combinations of bases are called genes. Their arrangements are codes for making distinct types of proteins. Joined together in long DNA strands, these genes form x- and y-shaped chromosomes, of which nearly all humans have 24.

A complete set of DNA for a species is called a genome.

Illustration courtesy U.S. Department of Energy


NEWS FEEDS    After installing a news reader, click on this icon to download National Geographic News's XML/RSS feed. After installing a news reader, click on this icon to download National Geographic News's XML/RSS feed.

Get our news delivered directly to your desktop—free.
How to Use XML or RSS

ADVERTISEMENT

NATIONAL GEOGRAPHIC'S PHOTO OF THE DAY

50 Drives of a Lifetime

Listen to your favorite National Geographic news daily, anytime, anywhere from your mobile phone. No wires or syncing. Download Stitcher free today.