'The heart has 4 chambers: 2 atria & 2 of these lower chambers'
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THE BODY HUMAN: The heart has 4 chambers: 2 atria & 2 of these lower chambers
The heart has 4 chambers: 2 atria & 2 of these lower chambers
The heart has 4 chambers: 2 atria & 2 of these lower chambers
THE BODY HUMAN
ventricles
THE BODY HUMAN