CHAPTER OUTLINE
■ HORMONES
Modes of Transmission
Biochemistry
■ PITUITARY GLAND
Anterior Pituitary
Anterior Pituitary Hormones
Posterior Pituitary and Its Hormones
■ THYROID GLAND
Thyroid Hormones
■ PARATHYROID GLANDS
Parathyroid Hormone and Calcium Ion Regulation
■ ADRENAL GLANDS
Hormones of the Adrenal Cortex
Glucocorticoid Functions and Regulation
Mineralocorticoid Functions and Regulation
Hormones of the Adrenal Medulla
■ PANCREATIC GLAND
Hormones of the Pancreas
Control of Insulin and Glucagon Secretion
■ PROSTAGLANDINS AND THEIR FUNCTIONS
The endocrine system is considered to be one of the animal body’s communication systems and its products (the hormones) help send messages to other cells.
The other communication system is the nervous system, in which nerve networks conduct messages from cells in one part of the body to cells in another part. The nervous system uses physical structures (neurons) to transmit messages (impulses), but the endocrine system uses the body fluids (humors) as its medium to transmit messages (hormones). Because of this, control by the latter system is referred to as humoral control, in contrast to neural control.The principal function of neural and humoral communication is control or regulation of various body functions. Nerve impulses traveling from the brain to the heart by way of the vagus nerve assist in the control of heart activities. Similarly, thyroid hormones are released from thyroid gland cells and circulated by the blood and interstitial fluids to all cells of the body to assist in the regulation of metabolic rate.
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