The Endocrine System
Controls many body functions exerts control by releasing special chemical substances into the blood called hormones Hormones affect other endocrine glands or body systems Regulate growth, development, metabolism, reproductive processes
Hormones need a specific receptor on a specific cell to do their job
Major Glands of the Endocrine system Pineal Hypothalamus Pituitary Thyroid Parathyroid Pancreas Adrenal Ovaries Testes
The Glands Hypothalamus Links the nervous system to the endocrine system Pineal Gland Located in the brain and produces melatonin
The Pituitary Gland Pituitary gland: a small gland located on a stalk hanging from the base of the brain – AKA The Master Gland –Primary function is to control other glands. –Produces many hormones. –Secretion is controlled by the hypothalamus in the base of the brain.
The Pituitary Gland The Pituitary Gland is divided into 2 areas, which differ structurally and functionally each area has separate types of hormone production. The two segments are the Posterior and Anterior pituitary
The Hormones of the Pituitary The two segments are: Posterior Pituitary produces: – oxytocin – antidiuretic hormone (ADH) Anterior Pituitary produces: thyroid-stimulating hormone (TSH) growth hormone (GH) adrenocorticotropin (ACTH) follicle-stimulating hormone (FSH) luteinizing hormone (LH) Prolactin (PRL) Melanocyte stimulating hormone (MSH)
The Thyroid Gland Lies in the anterior neck just below the larynx Has two lobes located on either side of the trachea (connected by a band of tissue called isthmus) Sacs within the gland are called colloids and within them are the hormones: Thyroxine (T4) Triiodothyronine (T3) Calcitonin
The Parathyroid Gland Small, pea-shaped glands, located in the neck near (para) the thyroid Most people usually have 4 Produces Parathyroid hormone (PTH)
The Pancreas Islets of Langerhans A key gland (also considered an organ in the digestive system!!) located near the folds of the duodenum Has both endocrine and exocrine functions Has a specialized tissue called Islets of Langerhans, in which endocrine functions occurs include 3 types of cells which secrete an important hormone: alpha ( ) beta ( ) delta ( )
The Pancreas Alpha cells ( ) release glucagon Beta Cells ( ) release insulin (antagonistic to glucagon) Delta Cells ( ) produce somatostatin
The Adrenal Gland It is two small glands located atop of both kidneys Each has two divisions with different functions Adrenal Medulla secretes (ties in closely with the sympathetic component of ANS): Norepinephrine Epinephrine Adrenal Cortex secretes: Gluticocorticoids Mineralocorticoids Androgenic hormones
Gonads Associated with human reproduction: Female-ovaries, Male-testis Both genders are controlled by: Luteinizing Hormone (LH) Follicle stimulating hormone (FSH) Ovaries Located in the abdominal cavity adjacent to the uterus (produces eggs) Hormones it produces: Estrogen (E) Progesterone (some) Testosterone (T) Testis Located in the scrotum (produces sperm) Hormones it produces: Testosterone (T)