Cellular & Microscopic Biology

Scientists have found that ancient fossilized chlorophyll was dark red and purple in its concentrated form, which means that when diluted by water or soil, it would have lent a pink cast to earth and sea.

By Laurie L. Dove

Viruses need hosts to replicate and reproduce. So if a virus has no host, how long can it survive? It depends on a lot of factors.

By Carrie Whitney, Ph.D.

Bacteria are both friend and foe to humanity. They cause and cure health problems, make rotting food stink and give sourdough its delicious taste. Find out how these countless tiny microbes accomplish all of this and more.

By Marianne Spoon

Your body replaces billions (with a b!) of cells every day. In about 100 days, 30 trillion be replaced, but does that mean you're a new person, too?

By Chris Opfer & Allison Troutner

Viruses, viroids and prions are microscopic, infectious particles with a common, despicable goal - but the way each goes about achieving that goal is different.

By Debra Ronca

You won't find some of history's biggest killers on this list, but you will find at least one disease that will make you want to bite something and another that might make you break out in "elevated pustules." Curious yet?

By Garth Sundem