Endocrine System

The Endocrine System is a series of specialized cells and glands that secrete HORMONES. HORMONES are substances the regulate the activity of other cells in the body. Some regulate growth, development, behavior, etc. ENDOCRINE GLANDS are organs that secrete the hormones, usually into the bloodstream. EXOCRINE GLANDS are similar to endocrine glands but can also secrete hormones through ducts (tubes) to specific locations, like sweat glands, salivary glands, digestive glands.

Types of Hormones Amino Acid Based Steroid Hormones

Amino Acid Hormones Water soluble Composed of 1 to 200 amino acids (proteins) Work on the cell membrane Activate or deactivate enzymes

Steroid Hormones Fat soluble Work in the cytoplasm or nucleus Activate or deactivate gene expression

Endocrine Glands Endocrine glands are located throughout the body. The HYPOTHALAMUS and PITUITARY GLAND control the initial release of many hormones.

Endocrine Coloring

HYPOTHALAMUS and PITUITARY GLAND The HYPOTHALAMUS is An area of the brain that coordinates many activities of the nervous and endocrine systems It responds to information by sending instructions in the form of hormones to the pituitary gland. The PITUITARY GLAND is right below the hypothalamus and stores hormones.PITUITARY GLAND The Pituitary gland regulates most of the hormones released around the body, including the growth hormone.

Thyroid Gland The thyroid gland is located near the larynx and secretes hormones which regulate heart rate, blood pressure, body temp, and also metabolic rates. Abnormal thyroid activity can cause overactivity (weightloss, high blood pressure and heart rate) or the opposite (weight gain, lethargy, low heart rate).

Adrenal Glands Located above each kidney Produce epinephrine and norepinephrine (adrenaline and noradrenaline) Fight-or-Flight Fight or Flight example

Gonads Ovaries in females, Testes in males Produce sex hormones which begin at puberty

Pancreas The PANCREAS is an organ that secretes hormones to regulate the level of sugar in the blood. Insulin lowers the blood sugar level by stimulating cells and muscles to use it for energy Lack of insulin or too much insulin= diabetes

Brain Pop! Endocrine System