02 Reproduction in Lower and Higher Animals - part 10 - Fate of germinal layers

02 Reproduction in Lower and Higher Animals - part 10 - Fate of germinal layers


Fate of germinal layers: 

Ectoderm :
  • Ectoderm gives rise to epidermis  of skin, hair, nails, sweat glands,  salivary glands, mammary glands,  lacrimal glands, sebaceous glands,  cornea, lens, retina, conjunctiva,  nasal epithelium, enamel of teeth, internal and external ear, foregut, hindgut, adrenal medulla, anterior and posterior pituitary, pineal  gland, entire nervous system. 

Mesoderm  : 
  • Mesoderm forms all types of muscles (except iris muscles ciliary muscles of eye which originate from ectoderm), connective tissues, dermis of skin, adrenal cortex, heart,blood, blood vessels, lymphatic vessels, middle ear, dentine of  teeth, urinary and reproductive ducts, gonads, kidneys, sclera and choroid of eye.

Endoderm : 
  • Endoderm devlops into epithelium of mid- gut, glands of   stomach and intestine, tongue,  tonsils, lungs, trachea, bronchi,larynx, urinary bladder, vagina, liver, pancreas, thyroid gland, parathyroid gland, thymus gland,  Eustachian tube,epithelium of urethra, lining of  middle ear.

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