The right and left cerebral hemispheres are interconnected by the

The _____ is considered the pacemaker of the heart

A) sinoatrial node B) atrioventricular node C) Purkinje fiber D) bundle branch

________ is the net movement of molecules from an area of relatively high concentration to an area of relatively low concentration

A) Molecular dispersion B) Diluting C) Filtration D) Diffusion