Which nerve provides parasympathetic innervation to the midgut?

The vagus nerve is the primary nerve that provides parasympathetic innervation to the midgut. It innervates structures derived from the embryonic midgut, including parts of the small intestine (such as the jejunum and ileum) and the proximal two-thirds of the colon (up to the transverse colon).

The vagus nerve is part of the cranial nerves and plays a crucial role in the autonomic nervous system, particularly in stimulating digestive processes. Its parasympathetic fibers help to increase intestinal motility and promote glandular secretions, facilitating digestion and absorption of nutrients in the midgut.

In contrast, the other choices involve different physiological roles or regions. The pudendal nerve primarily supplies somatic innervation to the pelvic floor muscles and does not provide parasympathetic fibers. The pelvic splanchnic nerve is involved in innervating the hindgut (the last third of the colon and pelvic organs), while the hypogastric plexus is associated with sympathetic innervation to the pelvic organs rather than parasympathetic input. Therefore, the vagus nerve is correctly identified as the source of parasympathetic innervation for the midgut.