Fish
Their are 2 heart chambers.
4 chambers
Clams have the most complex heart of the mollusks, with 3 chambers.
A snails heart has 2 chambers.
Sharks have 2 chambers
some only have three chambers
The left atrium and right atrium receive blood coming into the heart.
the 2 lower chambers of the heart
some only have three chambers
The dog's circulatory system is quite similar to that of humans. The heart has four chambers. The two upper chambers are the left and right atria, while the stronger, lower chambers are the right and left ventricles.
The human heart has four chambers connected by valves. We have 2 smaller chambers on the upper half of our heart and two larger chambers on the bottom of our heart. The smaller chambers are called atria; the larger chambers are called ventricles. So we refer to these chambers as right and left atrium, and right and left ventricle.
No, not all animals have the same number of chambers as humans.