Differential interference contrast image of a rotifer (Floscularia ringens) feeding. Its rapidly beating cilia (hair-like structures) bring water that contains food to the rotifer. When their cilia be...

Toxicysts, extrusive organelles, (sometimes called extrusomes in protistan lingo) in the proter (or anterior daughter) of a dividing cell. Toxicysts can be very long and are aligned along microtubular...

High resolution image of toxicysts, extrusive organelles, (sometimes called extrusomes in protistan lingo) in the proter (or anterior daughter) of a dividing cell. Toxicysts can be very long and are a...

Colorized scanning electron micrograph of a human embryonic stem cell (gold) growing on a layer of supporting cells (fibroblasts). Stem cells are derived from very early embryos and can either be grow...