The functions of thyroxine and tri-iodothyronine ’ are as follows:
(a) They regulate the metabolic rate of the body and thus maintain basal metabolic rate.
(b) They stimulate protein synthesis and promote growth of the body tissues.
(c) They regulate the development of mental faculties.
(d) As they increase heat production, they maintain body temperature.
(e) They help in metamorphosis of tadpole into adult