Overview

Ectoderm
- Surface ectoderm
  - Anterior pituitary (Rathke pouch)
    - Anterior pituitary gland (adenohypophysis): develops from oral ectoderm (Rathke pouch)
    - Posterior pituitary gland (neurohypophysis): develops from neural ectoderm
  - 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*