Biology in the background The heart is mainly made up of muscle tissue that pushes blood throughout the body. In mammals, including humans, this muscle is divided into four chambers: two ventricles ...

Each side of the heart consists of an atrium and a ventricle which are two connected chambers. The atria (plural of atrium) are where the blood collects when it enters the heart. The ventricles ...

Each side of the heart consists of an atrium and a ventricle which are two connected chambers. The atria (plural of atrium) are where the blood collects when it enters the heart. The ventricles ...

This is the lub sound you hear. It then pauses at the atrioventricular (AV) node which sits between the atria and ventricle before being relayed across the ventricle, causing it to contract.

CLEVELAND—Researchers at Case Western Reserve University, University Hospitals and Houston Methodist will harness the power ...

This heart organoid has atria- and ventricle-like structures and also exhibits beating movement. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to ...

This represents the time that it takes for the electrical impulse generated in the sinus node to travel through the atria and across the atrioventricular node to the ventricles. The normal PR ...

This is termed “AV dissociation.” In this situation, the ventricles never see action potentials originating from the atria and compensate by making action potentials of their own. However ...