ABSTRACT
The endocrine system includes all the body organs that synthesize and secrete hormones. The chief endocrine organs (glands) are the hypothalamus, hypophysis (pituitary gland), epiphysis, thyroid gland, parathyroid glands, pancreas, suprarenal glands, testes, ovaries and placenta. Other organs that have some endocrine function are the liver, kidneys, stomach, and intestines. Development of some of the above-mentioned organs has been described with other systems. Only the endocrine gland has not been discussed before. The hypothalamus, pituitary, suprarenals, pineal (epiphysis) and islets of Langerhans will be covered here. Although early development of the thyroid gland, parathyroids, is discussed along with the pharyngeal apparatus, their endocrine development will also be included.
