Malpighian Tubule Stellate Cells (Star-Shaped Water Movers)

Little stars in the tube wall

Insects like fruit flies and mosquitoes clean their blood with long, thin tubes called Malpighian tubules. They do the job your kidneys do.

Most of the tube wall is made of big primary cells. But here and there are smaller stellate cells. "Stellate" means star-shaped. In fruit flies, these cells have thin arms that spread out between their big neighbors, like a star.

Water and salt gates

The big primary cells pump salt into the tube. The stellate cells help the rest of the liquid follow.

• They let a different kind of salt, called chloride, move through.
• They have tiny water channels, like gates, that let water pass through quickly.
• When the insect needs to get rid of extra water fast, a hormone message tells the stellate cells to open up.

Your kidneys also get hormone messages that tell them to keep water or let it go!

Stellate cell quiz