The heart is innervated by the ______ nervous system.

• A. somatic
• B. autonomic
• C. central
• D. enteric

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the role of the nervous system in controlling the heart. The heart's function is regulated involuntarily, meaning it does not require conscious control. This is a key clue to identifying the correct nervous system involved.
2. Step 2: Review the types of nervous systems. The somatic nervous system controls voluntary movements, such as skeletal muscle actions. The autonomic nervous system regulates involuntary functions, including heart rate, digestion, and respiratory rate. The central nervous system consists of the brain and spinal cord, and the enteric nervous system specifically governs the gastrointestinal tract.
3. Step 3: Focus on the autonomic nervous system. It has two branches: the sympathetic division, which increases heart rate during stress or activity, and the parasympathetic division, which decreases heart rate during rest.
4. Step 4: Eliminate incorrect options. The somatic nervous system is not involved because it controls voluntary actions. The central nervous system is not directly responsible for heart innervation, and the enteric nervous system is specific to the digestive system.
5. Step 5: Conclude that the autonomic nervous system is the correct answer, as it is responsible for the involuntary regulation of the heart's activity.