Zebrafish have a heart and a circulatory system similar to that of humans, but with some important differences. Our hearts have two atria and two ventricles; the atria receive blood from the lungs and ...

This is a tissue sample from a zebrafish heart and its surrounding tissues. The golden strands are the muscle cells (1) that make up the ventricle of its heart. The surrounding blue dots are the ...

Artistic representation of heart regeneration: Hmga1 in green symbolically flows from the border zone of a zebrafish heart (top right) to the injured border zone of a mouse heart (left).