Find similarities in the structure of red blood cells of a person and a frog.

The erythrocytes of frogs and humans have the same function – the transfer of oxygen and carbon dioxide. This is provided by hemoglobin. It is composed of heme and globin. Heme contains iron, thanks to which it is possible to create bonds with oxygen. But the structure of frog erythrocytes is very different from human ones. They are much larger and have a core. Their shape is almost spherical. Because of this, the same volume of frog blood carries much less oxygen than human blood. Our red blood cells are devoid of a nucleus and are smaller in size.