Which of the following pairs are the mesoderm derivatives? |
Pineal gland, kidneys . Heart, primordial germ cells. Spleen,notochord . Salivary gland, internal ear . |
Spleen,notochord . |
The correct answer is Option (3) - Spleen,notochord . Each germ layer give rise to the specific tissues, organs and organ-systems.The germ layers have the same fate in all animals. 1.Ectoderm: It give rise to (i) epidermis of skin, and epidermal derivatives (glands hair, nails) ,(ii) nervous system, (iii) medulla of adrenal gland, posterior and intermediate lobes of pituitary gland, pineal gland, (iv) eye (conjunctiva, cornea, lens retina, iris and ciliary muscles) , (v) internal ear, (vi) nasal epithelium, (vii) lining of stomodaeum and protodaeum, (viii) lining of external auditory canal, (ix) lacrimal gland, salivary glands,(x) enamel of teeth. 2.Mesoderm: It produces (i) heart, blood and lymph vessels , (ii) sclera and choroid of eye,(iii) wall of gut except its lining epithelium , (iv) pericardium and pleura ,(v) dermis of skin, (vi) most muscles , (vii) connective tissues , (viii) peritoneum , (ix) kidneys, (x) cortex of adrenal gland, (xi )gonads, (xii)urinary and reproductive ducts, (xiii)spleen ,(xiv) most of skeleton,(xv) dentine of teeth, (xvi)mesenteries and notochord. 3. Endoderm : It forms (i) lining of gut except that of stomodaeum and protodaeum ,(ii) gastric and intestinal glands,tongue epithelium,liver, pancreas anterior lobe of pituitary gland , thyroid gland, parathyroid glans, thymus gland, (iii) lining of trachea,bronchi and lungs, (iv) lining of urinary bladder, (v) lining of middle ear, (vi) primordial germ cells and (vi) greater part of prostate. |