Thyroid hormone (TH) is the most important hormone in frog metamorphosis, a developmental process which will not occur in the absence of TH but can be induced precociously by exogenous TH.

How is metamorphosis controlled in insects and frogs?

This process of metamorphosis in frogs is controlled by the thyroid gland that releases thyroxine in the presence of iodine in water. ... Whereas the process of metamorphosis in insects is controlled by the insect hormones.

How does metamorphosis occur in frogs?

Metamorphosis is another word for the changes an animal makes during its life cycle. During a frog's metamorphosis, an egg will hatch into a tadpole, which will then develop back legs first, then front legs, and become a full grown adult frog!