Juvenile hormone is a class of insect hormones which are secreted by the corpora allata and promote retention of juvenile characters. Thymosin and calcitonin hormones are secreted by thyroid gland. Thyroxin hormone is secreted from the thymus gland. Mineralocorticoids, glucocorticoids and gonadocorticoids are secreted from adrenal cortex whereas epinephrine and nor epinephrine are secreted from adrenal medulla.