Which division of the autonomic nervous system is primarily responsible for the ability to focus the eyes for close vision (accommodation)?

• A. Enteric nervous system
• B. Sympathetic division
• C. Parasympathetic division
• D. Somatic nervous system

Answer: (C)

Verified step by step guidance

1. Understand the role of the autonomic nervous system (ANS), which is divided into the sympathetic and parasympathetic divisions, and controls involuntary functions such as heart rate, digestion, and pupil dilation.
2. Recognize that accommodation, the ability to focus the eyes for close vision, involves the contraction of the ciliary muscles in the eye to change the shape of the lens.
3. Learn that the parasympathetic division of the ANS is responsible for 'rest and digest' activities, including promoting relaxation and energy conservation, which includes controlling the ciliary muscles for accommodation.
4. Contrast this with the sympathetic division, which is responsible for 'fight or flight' responses, such as dilating the pupils for distant vision rather than close vision.
5. Conclude that the parasympathetic division is primarily responsible for accommodation, as it facilitates the contraction of the ciliary muscles to focus the lens for close vision.