Questions: Dual innervation refers to an organ receiving Select one: a. two nerves from the spinal cord b. both sympathetic and parasympathetic nerves c. both autonomic and somatomotor nerves d. nerves from both the brain and the spinal cord

The answer is (b): both sympathetic and parasympathetic nerves.

Explanation for each option: a. Two nerves from the spinal cord - This is incorrect because dual innervation specifically refers to the involvement of both divisions of the autonomic nervous system, not just the origin of the nerves. b. Both sympathetic and parasympathetic nerves - This is correct because dual innervation means that an organ receives input from both the sympathetic and parasympathetic branches of the autonomic nervous system, which often have opposing effects. c. Both autonomic and somatomotor nerves - This is incorrect because dual innervation refers to the two branches of the autonomic nervous system, not the combination of autonomic and somatomotor nerves. d. Nerves from both the brain and the spinal cord - This is incorrect because dual innervation is about the types of autonomic nerves (sympathetic and parasympathetic) rather than the anatomical origin of the nerves.

Summary: Dual innervation refers to an organ receiving both sympathetic and parasympathetic nerves.