The Endocrine System: GLANDS:
Lecture Objectives: Chapters 11, 14Upon completion of the lectures and chapters, you should be able to:
Upon completion of the lab exercises, you should be able to:
- Distinguish between endocrine and exocrine glands.
- Define the terms hormone, hypersecretion and hyposecretion.
- Identify and locate the primary endocrine glands and list the major hormones produced by each gland.
- Describe the mechanisms of nonsteroid and steroid hormone action.
- Explain how negative and positive feedback mechanisms regulate the secretion of endocrine hormones.
- Define and explain the importance of prostaglandins.
- Identify the principal functions of each major endocrine gland and the hormones that each releases.
- Describe the conditions that may result from hyposecretion or hypersecretion of endocrine hormones, including gigantism, diabetes insipidus, goiter, cretinism, diabetes mellitus, and glycosuria.
- Describe the primary functions of blood.
- Describe the characteristics of the blood plasma.
- List the formed elements of blood and identify the most important function of each.
- Discuss the structure and function of RBC's and how the RBC numbers and hemoglobin content may change to produce anemia.
- Describe ABO and Rh blood typing.
- Discuss the structure and function of WBC's.
- Explain the steps involved in blood clotting.
- Define the following medical terms associated with blood:
- Acidosis
- Alkalosis
- Serum
- Hematocrit
- Hemoglobin
- Anemia
- Sickle cell
- Polycythemia
- Erythroblastosis fetalis
- Rh factor
- Leukocytosis
- Leukopenia
- Phagocytosis
- Fibrinogen
- Thrombosis
- Neutrophilia
- Neutropenia
- Antigen
- Antibody
Upon completion of the lab exercises, you should be able to:
- Identify each major endocrine gland on models or charts.
- Name the principal hormones secreted by the major endocrine glands and describe their main functions.
- Name the components of blood.
- Describe the structure, characteristics and functions of red blood cells, white blood cells and platelets.
- Identify RBC's, WBC's and platelets on prepared blood smear slides.
- Describe the importance of ABO and Rh blood type testing.
- Perform an ABO and Rh blood type test on simulated blood.
- Describe the importance of the following blood tests and identify their components: CBC, differential WBC count, hematocrit, hemoglobin, and coagulation time.
- Interpret given sets of blood tests and determine whether or not they are normal or abnormal, low or high, and some conditions they may be linked with.
Important Terminology:
Endocrine system - the glands that secrete chemicals called hormones into the bloodstream that bind to target cells
Target cells - specific for specific hormones and have receptors on their surface that recognize and bind to them, at which point these hormones cause changes in activity in them to assist in maintaining homeostasis (balance)
Receptors - on surface of target cells for receiving hormone chemicals
Major Endocrine Glands:
Pineal Gland (Body)
Tiny gland that secretes the hormone melatonin that regulates Circadian rhythms and the sleep-wake cycle
HypothalamusLocated inferior to the thalamus
Controls the pituitary gland
"Master Gland"
Infundibulum - stalk that connects it to the pituitary gland
Pituitary Gland
2 lobes: anterior and posterior
Anterior: makes and secretes 7 hormones: human growth hormone (hGH), thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), adrenocorticotropic hormone (ACTH), melanocyte-stimulating hormone (MSH)
Posterior: smaller; stores and releases 2 hormones into the bloodstream: antidiuretic hormone (ADH), oxytocin (OT)
Thyroid Gland
Butterfly-shaped gland that lies on both sides of the trachea near the larynx and has 2 lobes with a connecting isthmus.
Synthesizes and secretes calcitonin and thyroid hormones (TH), thyroxine (T4) or tetraiodothyronine and triiodothyronine (T3).
Parathyroid Glands
4 small glands embedded in the posterior surface of the thyroid gland that secrete parathyroid hormone (PTH)
ThymusLies behind the sternum and is part of the immune system where T-lymphocytes mature; secretes thymosin; atrophies with age
Adrenal Glands
Two triangular-shaped glands, each of which sit atop the kidneys.
Each is surrounded by a capsule and has a larger outer cortex and a central medulla.
Adrenal cortex - secretes mineralcorticoids (aldosterone) and glucocorticoids (cortisol) and androgens
Adrenal medulla - secretes epinephrine and norepinephrine
Pancreas-Largest gland in the body; head, body and tail.
Produces enzymes.
Pancreatic- duct - duct that secretes enzymes that aid in digestion
Pancreatic islets (islets of Langerhans) - little islands among exocrine cells that secrete glucagon (alpha cells) and insulin (beta cells)
Ovaries-Female gonads in the pelvic cavity that secrete estrogen and progesterone
Testes-Male gonads located within the scrotum that form sperm and produce and secrete androgens, primarily testosterone
Endocrine system - the glands that secrete chemicals called hormones into the bloodstream that bind to target cells
Target cells - specific for specific hormones and have receptors on their surface that recognize and bind to them, at which point these hormones cause changes in activity in them to assist in maintaining homeostasis (balance)
Receptors - on surface of target cells for receiving hormone chemicals
Major Endocrine Glands:
Pineal Gland (Body)
Tiny gland that secretes the hormone melatonin that regulates Circadian rhythms and the sleep-wake cycle
HypothalamusLocated inferior to the thalamus
Controls the pituitary gland
"Master Gland"
Infundibulum - stalk that connects it to the pituitary gland
Pituitary Gland
2 lobes: anterior and posterior
Anterior: makes and secretes 7 hormones: human growth hormone (hGH), thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), adrenocorticotropic hormone (ACTH), melanocyte-stimulating hormone (MSH)
Posterior: smaller; stores and releases 2 hormones into the bloodstream: antidiuretic hormone (ADH), oxytocin (OT)
Thyroid Gland
Butterfly-shaped gland that lies on both sides of the trachea near the larynx and has 2 lobes with a connecting isthmus.
Synthesizes and secretes calcitonin and thyroid hormones (TH), thyroxine (T4) or tetraiodothyronine and triiodothyronine (T3).
Parathyroid Glands
4 small glands embedded in the posterior surface of the thyroid gland that secrete parathyroid hormone (PTH)
ThymusLies behind the sternum and is part of the immune system where T-lymphocytes mature; secretes thymosin; atrophies with age
Adrenal Glands
Two triangular-shaped glands, each of which sit atop the kidneys.
Each is surrounded by a capsule and has a larger outer cortex and a central medulla.
Adrenal cortex - secretes mineralcorticoids (aldosterone) and glucocorticoids (cortisol) and androgens
Adrenal medulla - secretes epinephrine and norepinephrine
Pancreas-Largest gland in the body; head, body and tail.
Produces enzymes.
Pancreatic- duct - duct that secretes enzymes that aid in digestion
Pancreatic islets (islets of Langerhans) - little islands among exocrine cells that secrete glucagon (alpha cells) and insulin (beta cells)
Ovaries-Female gonads in the pelvic cavity that secrete estrogen and progesterone
Testes-Male gonads located within the scrotum that form sperm and produce and secrete androgens, primarily testosterone
- Pineal Gland
- Pituitary Gland
- Thyroid Gland
- Thymus
- Adrenal Gland
- Pancreas
- Ovary
- Testes