Question: Where are the group of cells that control the natural resting heart rate found?
Disambiguated questions and answers: question: Where are the group of  muscle cells that control the natural resting heart rate found?
Where are the cells that control the resting heart rate found if the SA node is damaged?
Where are the cells that control the resting heart rate found?
answer: atria
Right Atrium
Atrioventricular node
AV node
SA node
sinoatrial node
Natural Questions answer: sinoatrial node (from the Wikipedia article "Pacemaker potential")