What is the term used for the divider between the heart chamber walls?

The term used for the divider between the heart chamber walls is "septum." The septum is a critical structure within the heart, serving to separate the two atria (the upper chambers) from each other and also the two ventricles (the lower chambers) from one another. This separation is vital for the proper functioning of the heart, as it allows for effective circulation of blood by maintaining distinct pathways for oxygenated and deoxygenated blood.

The other terms listed do not accurately describe the divider between heart chambers. "Atria" refers to the two upper chambers of the heart, while "ventricle" pertains to the two lower chambers. "Wall" is a generic term and does not specify the anatomical structure that provides the division between the chambers. The septum's role is essential in ensuring the heart operates efficiently, preventing mixing of blood types and maintaining proper blood flow throughout the circulatory system.