What is the difference between the endocrine gland and the exocrine gland?
Endocrine gland is a gland whose secretions (known as hormones) are collected by the blood and reach the tissues by the circulation. The hypophysis (pituitary) and the adrenals are instance of endocrine glands. Exocrine gland is a gland whose secretions are released externally by ducts (into the intestinal lumen, skin, mouth, etc.).