When muscles of the heart relax and contract rhythmically (1 heart beat) that is known as a __________.
Answer: cardiac cycle
When muscles of the heart relax and contract rhythmically (1 heart beat) that is known as a __________.
Answer: cardiac cycle
If the answers is incorrect or not given, you can answer the above question in the comment box. If the answers is incorrect or not given, you can answer the above question in the comment box.