Embriologic Derivatives

Ectoderm

• Surface Ectoderm

  • Anterior pituitary (Rathke pouch)

  • Lens & cornea.

  • Inner ear sensory organs, olfactory epithelium

  • Nasal & oral epithelial linings, salivary glands

  • Epidermis, sweat & mammary glands

• Neural Tube

  • Brain & spinal cord

  • Posterior pituitary, pineal gland

  • Retina

• Neural Crest

  • Neural ganglia, adrenal medulla

  • Schwann cells; pia & arachnoid mater

  • Aorticopulmonary septum & endocardial cushions

  • Branchial arches (bones & cartilage)

  • Skull bones

  • Melanocytes

Mesoderm

• Muscles (skeletal, cardiac & smooth)

• Connective tissue, bone & cartilage

• Serosal linings (eg, peritoneum)

• Cardiovascular & lymphatic system

• Spleen & hemopoietic cells

• Kidney & ureters, internal genitalia

• Adrenal cortex

Endoderm

• Gastrointestinal tract, liver, pancreas

• Lungs

• Thymus, parathyroids, thyroid follicular cells

• Middle ear epithelium

• Bladder & urethra

• Parafollicular (C) cells