Endocrine glands secrete hormones into the bloodstream and are thereby distributed to target organs or tissues. 294
15.2 Hypothalamus and Pituitary Gland
The hypothalamus, a part of the brain, controls the function of the pituitary gland, which consists of the anterior pituitary and the posterior pituitary. 296The anterior pituitary produces several hormones, some of which control other endocrine glands. 296
15.3 Thyroid and Parathyroid Glands
The thyroid produces hormones that speed metabolism and another that lowers the blood calcium level. Antagonistic to this activity, parathyroid glands produce a hormone that raises the blood calcium level. 299-300
15.4 Adrenal Glands
The adrenal glands produce hormones that help us respond to stress. 301
15.5 Pancreas
The pancreas secretes hormones that help regulate the blood glucose level. 304Diabetes mellitus occurs when cells are unable to take up glucose and it spills over into the urine. 305
15.6 Other Endocrine Glands
Many other tissues, although not traditionally considered endocrine glands, secrete hormones. 306
15.7 Chemical Signals
Hormones are chemical signals that influence the metabolism of their target cells. 309The endocrine system works with the other systems of the body to maintain homeostasis. 310 s