Question:
For the metamorphosis of tadpoles which of the following elements must be available in water?
(a) Chlorine
(b) Carbon
(c) Sulphur
(d) Iodine
Solution:
(d) For metamorphosis of tadpoles, iodine should be present in water. This is because metamorphosis is brought about by thyroxine hormone that
requires the presence of iodine for its production by thyroid gland.