Physiology S.A. node acts as a pacemaker of the hea because of the fact that it A Is capable of generating impulses spontaneously B Has rich sympathetic innervations C Has poor cholinergic innervations D Generates impulses at the highest rate 💡 Explanation S.A. node acts as a pacemaker of the hea because of the fact that it ✓ Correct Answer: D. Generates impulses at the highest rate