Popular in Human Anatomy and Physiology II
Popular in Biological Sciences
This 6 page Class Notes was uploaded by Jess Graff on Saturday February 20, 2016. The Class Notes belongs to BMS 508 at University of New Hampshire taught by Mary Katherine Lockwood, PhD in Spring 2016. Since its upload, it has received 17 views. For similar materials see Human Anatomy and Physiology II in Biological Sciences at University of New Hampshire.
Reviews for BMS 508
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 02/20/16
BMS 508.03 2/3/2016 Chapter 18 (cont) Endocrine System (cont) Parathyroid Glands 3 Effects of PTH o Stimulates osteoclasts and inhibits osteoblasts 2+ Accelerates mineral turnover and releases Ca from bone Reduces rate of calcium deposition in bone o Enhances reabsorption of Ca 2+ at kidneys, reducing urinary losses o Stimulates formation and secretion of calcitriol by the kidneys Effects complement or enhance PTH Also enhances Ca , PO 4absorption by digestive tract Adrenal Glands The Adrenal Glands o Lie along superior border of each kidney o Subdivided into: Superficial adrenal cortex Stores lipids, especially cholesterol and fatty acids Manufactures steroid hormones (corticosteroids) Inner adrenal medulla Secretory activities controlled by sympathetic division of ANS Produces epinephrine (adrenaline) and norepinephrine Metabolic changes persist for several minutes Adrenal Cortex o Subdivided into 3 regions Zona glomerulosa Zona fasciculata Zona reticularis Zona Glomerulosa o Outer region of adrenal cortex o Produces mineralocorticoids Example: aldosterone Aldosterone o Stimulates conservation of sodium ions and elimination of potassium ions o Increases sensitivity of salt receptors in taste buds o Secretion responds to: + Drop in blood Na , blood volume, or blood pressure Rise in blood K concentration Zona Fasciculata o Produces glucocorticoids o Example: cortisol (hydrocortisone) with corticosterone Liver converts cortisol to cortisone o Secretion regulated by negative feedback o Has inhibitory effect on production of: Corticotropin-releasing hormone (CRH) in hypothalamus ACTH in adenohypophysis Glucocorticoids o Accelerate glucose synthesis and glycogen formation o Show anti-inflammatory effects Inhibit activities of white blood cells and other components of immune system Zona Reticularis o Network of endocrine cells o Forms narrow band bordering each adrenal medulla o Produces androgens under stimulation by ACTH The Adrenal Medulla o Contains 2 types of secretory cells 1 produces epinephrine (adrenaline) 75 to 80% of medullary secretions The other produces norepinephrine (noradrenaline) 20 to 25% of medullary secretions Epinephrine and Norepinephrine o Activation of the adrenal medullae has the following effects: In skeletal muscles, epinephrine and norepinephrine trigger mobilization of glycogen reserves And accelerate the breakdown of glucose to provide ATP This combination increases both muscular strength and endurance In adipose tissue, stored fats are broken down into fatty acids Which are released into the bloodstream for other tissues to use for ATP production In the liver, glycogen molecules are broken down The resulting glucose molecules are released into the bloodstream Primarily for use by neural tissue, which cannot shift to fatty acid metabolism In the heart, the stimulation of beta 1 receptors triggers an increase in the rate and force of cardiac muscle contraction Pineal Gland • The Pineal Gland • Lies in posterior portion of roof of third ventricle • Contains pinealocytes • Synthesize hormone melatonin • Functions of Melatonin: • Inhibits reproductive functions • Protects against damage by free radicals • Influences circadian rhythms Pancreas • The Pancreas • Lies between: • Inferior border of stomach & proximal portion of small intestine • Contains exocrine and endocrine cells • Exocrine Pancreas • Consists of clusters of gland cells called pancreatic acini and their attached ducts • Takes up roughly 99% of pancreatic volume • Gland and duct cells secrete alkaline, enzyme-rich fluid • That reaches the lumen of the digestive tract through a network of secretory ducts • Endocrine Pancreas • Consists of cells that form clusters known as pancreatic islets, or islets of Langerhans • Alpha cells produce glucagon • Beta cells produce insulin • Delta cells produce peptide hormone identical to GH–IH • F cells secrete pancreatic polypeptide (PP) • Blood Glucose Levels • When levels rise: • Beta cells secrete insulin, stimulating transport of glucose across plasma membranes • When levels decline: • Alpha cells release glucagon, stimulating glucose release by liver • Insulin • A peptide hormone released by beta cells • Affects target cells • Accelerates glucose uptake • Accelerates glucose utilization and enhances ATP production • Stimulates glycogen formation • Stimulates amino acid absorption and protein synthesis • Stimulates triglyceride formation in adipose tissue • Glucagon • Released by alpha cells • Mobilizes energy reserves • Affects target cells • Stimulates breakdown of glycogen in skeletal muscle and liver cells • Stimulates breakdown of triglycerides in adipose tissue • Stimulates production of glucose in liver (gluconeogenesis) • Diabetes Mellitus • Characterized by glucose concentrations high enough to overwhelm the reabsorption capabilities of the kidneys • Hyperglycemia abnormally high glucose levels in the blood in general • Glucose appears in the urine, and urine volume generally becomes excessive (polyuria) • Diabetes Mellitus • Type 1 (insulin dependent) diabetes • Characterized by inadequate insulin production by the pancreatic beta cells • Persons with type 1 diabetes require insulin to live and usually require multiple injections daily, or continuous infusion through an insulin pump or other device • This form of diabetes accounts for only around 5–10% of cases; it often develops in childhood • Type 2 (non-insulin dependent) diabetes • Most common form of diabetes mellitus • Most people with this form of diabetes produce normal amounts of insulin, at least initially, but their tissues do not respond properly, a condition known as insulin resistance • Type 2 diabetes is associated with obesity • Weight loss through diet and exercise can be an effective treatment
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'