Small intestine anatomy and physiology

With a large surface area, the small bowel acts as a major site for breakdown and absorption of electrolytes, nutrients and water. The act of mixing and transit of digested and non-digested contents is assisted by a complicated but efficient contraction waves and highly regulated gut hormones. In addition, intestinal motility assists the barrier and immune function of small bowel which is vital for homeostasis with the gut microbiota. This chapter deals with functional significance of small intestine anatomy and physiology in relation with motility, a region of the gut that has been largely ignored, until recently.