Final answer:
The intrinsic firing rate of the AV node is 40-60 BPM. Bradycardia is a condition characterized by heart rates below 50 BPM.
Step-by-step explanation:
The intrinsic firing rate of the AV node is 40-60 BPM.
The SA node serves as the pacemaker of the heart and initiates impulses approximately 80-100 times per minute. However, if the AV node were blocked, it would generate a heart rate of 40-60 beats per minute. Rates lower than 50 beats per minute would indicate a condition called bradycardia and can result in inadequate blood flow to vital tissues.