What is the primary function of the sympathetic nervous system?

• A. To promote rest-and-digest activities by increasing gastrointestinal motility and secretion
• B. To transmit special sensory information (vision and hearing) from the head to the brainstem
• C. To prepare the body for stress by initiating the fight-or-flight response (e.g., increasing heart rate and dilating airways)
• D. To control voluntary skeletal muscle contraction via motor neurons of the somatic nervous system

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the role of the autonomic nervous system, which is divided into the sympathetic and parasympathetic divisions, each with distinct functions in regulating involuntary body activities.
2. Step 2: Recognize that the parasympathetic nervous system primarily promotes 'rest-and-digest' activities, such as increasing gastrointestinal motility and secretion, which conserves energy and supports digestion.
3. Step 3: Identify that the sympathetic nervous system is responsible for preparing the body for stressful or emergency situations by initiating the 'fight-or-flight' response, which includes increasing heart rate, dilating airways, and redirecting blood flow to muscles.
4. Step 4: Note that the transmission of special sensory information (vision and hearing) is a function of sensory pathways, not the sympathetic nervous system.
5. Step 5: Understand that voluntary skeletal muscle contraction is controlled by the somatic nervous system, which is separate from the autonomic nervous system and its sympathetic division.