Gastrointestinal System Embryology Quiz

Gastrointestinal System: Embryology

• At the beginning of the 4th week, the primordial gut is closed at the cranial end by the oropharyngeal membrane and at the caudal end by the cloacal membrane.
• The primordial gut gives rise to epithelia and glands from endoderm, and stroma from lateral plate splanchnic mesoderm.
• The epithelium within the stomodeum and epithelium of the proctodeum are derived from surface ectoderm.

Foregut

• The foregut is vascularized by the celiac trunk and gives rise to:
  • Primordial pharynx
  • Oral cavity
  • Teeth
  • Pharynx
  • Tongue
  • Tonsils
  • Salivary glands (submaxillary, submandibular, sublingual)
  • Upper respiratory system (nasal cavities, nasopharynx)
  • Lower respiratory system (larynx, trachea, bronchi, lungs)
  • Esophagus
  • Stomach
  • Duodenum
  • Liver
  • Extrahepatic biliary system (including gallbladder)
  • Pancreas

Development of Oral Cavity

• The pharyngeal apparatus consists of pharyngeal arches, pharyngeal membranes, pharyngeal pouches, and endoderm.
• The esophagus develops from foregut immediately caudal to the pharynx, is partitioned from the trachea by the tracheoesophageal septum, and elongates rapidly.

Development of Larynx

• The laryngeal ventricles form during the recanalization process.
• The recesses are bounded by folds of mucous membrane that become the vestibular folds and vocal folds.
• The epiglottis develops from the caudal part of the hypopharyngeal eminence, and its growth is rapid during the first three years after birth.
• The laryngeal muscles develop from myoblasts of the 4th and 6th pharyngeal arches and are innervated by branches of the vagus (CN X) nerve.

Test your knowledge of the embryological development of the gastrointestinal system with this quiz. Questions cover the closure of the primordial gut, layers giving rise to epithelia and glands, and more.