Ectoderm
- Neural tube – Nervous system ie. brain, spinal cord, arachnoid and pia matter
- Sensory epithelium of sensory organs
- Pituitary gland
- Medulla of suprarenal gland
- Lining of anterior oral cavity and lower anal canal
- External auditory meatus and outer tympanic membrane (ear drum)
- Epidermis of skin
Endoderm
1. Epithelial lining of:
- Respiratory tract
- GIT tract except anterior oral cavity
- Urinary bladder except trigone
- Urethra
- Eustachian tube
2. Parenchyma of:
- Tonsils
- Thyroid
- Parathyroid
- Thymus
- Liver
- Pancreas