Amazing!

Guess what it is! Guess what it is!

It's a Red Blood Cell squeezing through a hole in the spleen. Newer red blood cells are pretty deformable... which is how they fit through your tiny capillaries and provide oxygen to your body. Older red blood cells are not able to deform as well, and are filtered out by the spleen because they can't squeeze through these holes!

This picture was taken by an electronmicrograph.