Lens develops from?
Ans. c (Surface ectoderm). (Ref. Human Embryology by IB Singh, 6th/352)LENS# LENS develops from surface ectoderm.# Compared to the cornea, it has a much lower converging power of 17 diopters because of the relatively similar refractive indices of aqueous humor, lens, and vitreous body (cornea 42 D).# However, the lens is the only part of the refractive apparatus that is adjustable.# Adjustment to near vision (accommodation) therefore involves only the lens.# In addition, the lens functions as a UV filter for wavelengths between 300 and 400 nm and thus has a protective function for the macula.# Notching of the lens = "pseudocoloboma".# Wilson's disease can induce a yellow-green lens discoloration (chalcosis/ sunflower cataract).# Granular gold deposits located under the lens (chrysiasis lends) can occasionally occur after prolonged treatment with gold preparations (e. g. in primary chronic polyarthritis ).# Other medications, e.g., amiodarone or chlorpromazine, are sometimes deposited in the lens.# In patients with cataract, glittering cholesterol crystals are not infrequently found in the lens (so-called Christmas tree/ decoration cataract).
Endoderm
Mesoderm
Surface ectoderm
Neuroectoderm
Lens