We hope you find the new NASPGHAN Physiology series helpful. The following modules will walk you through basic GI Physiology. Each module has a powerpoint with talking points and a word document that provides a brief review of the topic. Cases and questions are woven into each module to spark conversation and give clinical relevance

Consider assigning each module to a fellow with a faculty mentor. The presenting fellow can modify the powerpoint with new cases, images, or questions and a list of the top ten learning points and even consider shortening the presentation to allow for more focused discussion. The fellow then presents the module with support from their faculty mentor. All of the fellows are provided with the word document to review prior to the presentation and to maintain for future board preparation.

We hope you have great educational success and look forward to your feedback! Special thanks to Christine Waasdorp Hurtado and Daniel Kamin for developing these educational modules.

Anatomy and Embryology

  • Understand the normal development of the caudal part of the foregut (esophagus, stomach, duodenum, liver, and gallbladder), midgut (intestines, colon), and hindgut (rectum)
  • Know the anatomic features of the stomach (gross, microscopic, neuromuscular)
  • Understand normal blood supply
  • Understand the normal development of the enteric nervous system
  • Understand common congenital anomalies

GI Secretions

  • Understand the stimuli responsible for the secretion of gastrointestinal hormones
  • Understand the mechanism of action responsible for the physiologic effects of various gastrointestinal hormones
  • Understand that peptic acidity (pH < 4.0) is present as young as 24 weeks' gestation
  • Understand the normal gastric secretory processes
  • Know how to evaluate gastric secretory processes
  • Know the functions of the gut-derived polypeptides
  • Know the location of hormone-secreting cells in the gastrointestinal tract
  • Understand the process of intracellular hormone processing in the gastrointestinal tract

Brief overview of GI Secretions

GI Secretions Slides

Absorption of Water, Ions, Vitamins and Minerals

  • Understand the mechanisms of intestinal transport of ions (eg, coupled/uncoupled electrolytes, calcium, phosphate)
  • Know the location of transport and secretion of ions
  • Understand the absorption of vitamins and minerals
  • Understand the phenomenon of changes in nutrient absorption (mucosal hypertrophy and changes in specific transport mechanisms) with luminal nutrient concentration
  • Mechanisms of diarrhea
  • Identify signs and symptoms of excess vitamin and mineral absorption and signs and symptoms of deficiency

Digestion of Protein

  • Understand the developmental sequence of digestive function
  • Understand the digestion and absorption of protein

Digestion of Carbohydrates

  • Understand the developmental sequence of digestive function
  • Understand the phenomenon of changes in nutrient absorption with changes in body stores of selected n
  • Understand the digestion and absorption of carbohydrates
  • utrients

Pancreas Physiology

  • Understand the normal development and anatomy of the pancreas

Digestion of Fats/Lipids

  • Understand the digestion and absorption of fat
  • Understand the role of the terminal ileum in regulating the enterohepatic circulation of bile acids
  • Understand the development of stimuli causing pancreatic secretion
  • Be aware of age-related deficiency in exocrine pancreatic function
  • Know the mechanisms by which pancreatic enzymes are activated
  • Know the co-factors necessary for pancreatic enzyme function


  • Know the characteristics and functions of different intestinal epithelial cells (eg, intraepithelial lymphocytes, mucosal lymphocytes, lymphoid cells in Peyer patches)
  • Understand the physiology of lymphocytes and consequences of antigen uptake in the gastrointestinal tract
  • Distinguish between the characteristics of immune function in the human immature and mature gastrointestinal tract
  • Know how breast feeding influences immune function in the gut
  • Understand how cytokines mediate inflammation and how their modulation may
  • Understand the secretory IgA system
  • Understand the the effects of enteric flora in intestinal morphology and function
  • Know the mechanism the prevent bacterial overgrowth in the Small intestine (motility, acide secretion, mucus and immunologi factors)
  • Identify organisms that are predominant in the colonic flora


  • Understand the components of motility, including esophageal, gastric, small intestinal, colonic, anorectal
  • Understand the neuronal and hormonal peptides that modulate gastrointestinal motility
  • Understand the ontogeny of gastrointestinal motility
  • Understand the nonpeptide chemical neurotransmitters that modulate gastrointestinal motility (including acetylcholine, norepinephrine, dopamine, serotonin, etc)
  • Understand how nitric oxide modulates gastrointestinal motility and in which disease states its function may be altered
  • Understand the differences between motility in the fed and fasted states
  • Understand the role of the extrinsic nervous system and the enteric nervous system in modulating gastrointestinal motility

Liver Physiology

  • Understand hepatic carbohydrate metabolism
  • Understand hepatic synthesis and metabolism of fatty acids and the role of the liver in lipid transport
  • Know serum proteins synthesized by the liver
  • Understand mechanisms of hepatic
  • Understand the concept of physiologic immaturity of hepatic function (eg, excretory function, bilirubin metabolism, bile acid metabolism)
  • Know the pathways of hepatic drug metabolism
  • Understand that taurine is a conditionally essential amino acid in early
  • Know the various biochemical parameters useful to assess hepatic integrity
  • Know mechanism of bilirubun production and differences with maturity
  • Understand bilirubin uptake, metabolism and excretion
  • Know Liver and gallbladder development and anatomy to include blood supply
Our Partners
The Association of Pediatric Gastroenterology and Nutrition Nurses
Help & Hope for Children with Digestive Disorders
Journal of Pediatric Gastroenterology and Nutrition
JPGN Reports