Adrenal cortex hormones are steroids in nature. They are classified into 3 groups:1.Mineralocorticoids, 2.Glucocorticoids, 3.Sex hormones.based on functions.
The endocrine part of the pancreas has many rounded collections of cells called as pancreatic islets (the islets of Langerhans).Islets of Langerhans consist of four types of cells.
3 hormones -Tetraiodothyronine,Tri-iodothyronine & calcitonin.T4 is known as thyroxine & it forms about 90% of total secretion,where as T3 is only 9%-10%.
Hormone does not act on the target cell directly but they combines with receptor to form hormone-receptor complex which executes the hormonal action.