What structures do fish and amphibians have for movement/how many chambers in there hearts?

Question

2 questions here!! Thanks peeps!

Answer 1

A fish heart has 2 chambers
The blood goes from the heart to gills, from the gills to the rest of the body, and then back to the heart. In most fish, the heart consists of four parts: the sinus venosus, the atrium, the ventricle, and the bulbus arteriosus.

Amphibians have a three-chambered heart with two atria and one ventricle.

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