1. Chapter 16
Endocrine System

2. Objective 1: Identify organs and structures of the endocrine system.
Chapter 16
Objective 1: Identify organs and structures of the endocrine system.

3. Endocrine System
The endocrine system is composed of glands distributed throughout the body:
pituitary gland
thyroid gland
parathyroid glands
hypothalmus
adrenal glands
islets of Langerhans of the pancreas
gonads (ovaries and testes)
thymus gland
Locate and discuss the glands on the diagram.

4. The Endocrine System This is an illustration of the endocrine system.
Note the pituitary gland is the only endocrine gland located in the skull.
Note the relationship between the thyroid and thymus glands.
Copyright © 2014, 2012, 2009, 2005, 2002, 1998, 1994, 1989, 1985 by Mosby, Inc., an affiliate of Elsevier Inc. All rights reserved.

5. Functions of the Endocrine System
The endocrine system regulates body activities through the use of chemical messengers called hormones, which when released into the bloodstream influence metabolic activities, growth, and development.
How does the nervous system regulate body activities?
Hormones secreted by the endocrine glands go directly into the bloodstream.
Endocrine glands are called ductless glands.

6. Endocrine Glands
pituitary: approximately the size of a pea, located at the base of the brain and is divided into two lobes
anterior lobe produces hormones
growth hormone (GH)
adrenocorticotropic hormone (ACTH)
thyroid-stimulating hormone (TSH)
gonadotropic: follicle-stimulating hormone (FSH), luteinizing hormone (LH)
prolactin releasing or lactogenic hormone (PRH)
Note the pituitary is divided into two lobes.
Note the variety of activities regulated by the anterior lobe of the pituitary gland.

7. Endocrine Glands (cont’d)
pituitary (cont’d)
anterior lobe produces hormones (cont’d)
antidiuretic hormone (ADH)
oxytocin
hypothalamus: located near the pituitary gland in the brain that secretes “releasing” hormones that functions to stimulate or inhibit the release of pituitary gland hormones
Note the interlocking relationship of the endocrine glands illustrated by the function of the hypothalamus in stimulating the pituitary gland.

8. Endocrine Glands (cont’d)
thyroid: largest endocrine gland located in the neck below the larynx
produces hormones
triiodothyronine (T3)
thyroxine (T4)
parathyroid: four small bodies embedded in the posterior lobes of the thyroid gland
produces parathyroid hormone (PTH)
The T3 and T4 hormones require iodine for their production.
Thyroxine is necessary for body cell metabolism.
What does the parathyroid do in the body?

9. Endocrine Glands (cont’d)
islets of Langerhans: clusters of endocrine tissue found throughout the pancreas
secretes hormones
insulin
glucagon
produces enzymes that facilitate digestion
Where would the name “islets of Langerhans” come from?
There are non-endocrine cells throughout the pancreas that perform non-endocrine digestions (with enzymes) and other non-endocrine functions.

10. Endocrine Glands (cont’d)
adrenal glands: paired glands, one above each kidney. The outer portion is called the cortex, and the inner portion is called the medulla.
secrete hormones
cortisol (hydrocortisone)
aldosterone
epinephrine (adrenaline), norepinephrine (noradrenaline)
What does cortisol do in the human body?
Aldosterone regulates electrolytes in the body.
What are electrolytes, and what do they do? What are some examples of electrolytes?
What does epinephrine do in the human body?
The adrenal gland also produces norepinephrine (noradrenaline).

11. Chapter 16
Objective 2: Define and spell word parts related to the endocrine system.

12. Combining Forms of the Endocrine System
aden/o
adren/o, adrenal/o
cortic/o
endocrin/o
parathyroid/o
pituitar/o
thyroid/o, thyr/o
What is the combining form for cortex? Which endocrine organ has a cortex?
What does the combining form parathyroid/o refer to?

13. Combining Forms Commonly Used with the Endocrine System Terms
acr/o
calc/i
dips/o
kal/i
natr/o
What is the combining form for “thirst”?
What does the combining form kal/i refer to?
What is the combining form for “sodium”?
Note: the combining forms for calcium and potassium use the combining vowel “i”

14. Suffix -drome What does the suffix -drome mean?
What does the term syn/drome mean?

15. Review Question Which of the following contains the word
root meaning potassium?
hypokalemia
hyponatremia
Answer: a) hypokalemia
Kal/i means potassium; natr/o means sodium.
Continue analyzing the terms.

16. Chapter 16
Objective 3: Define, pronounce, and spell disease and disorder terms related to the endocrine system.

17. Disease and Disorder Terms Built from Word Parts
acromegaly
adenitis
adenomegaly
adenosis
adrenalitis
adrenomegaly
hypercalcemia
hyperglycemia
hyperkalemia
hyperpituitarism
hyperthyroidism (animation on Student Evolve site)
hypocalcemia
hypoglycemia
hypokalemia
hyponatremia
hypopituitarism
hypothyroidism (animation on Student Evolve site)
panhypopituitarism
parathyroidoma
thyroiditis
What does the medical term acromegaly mean?
What is the medical term for “enlargement of a gland”?
Which term would mean “excessive calcium in the blood”? “Deficient level of calcium in the blood”?
What is the medical term for “deficient level of potassium in the blood”?

18. Chapter 16
Objective 6: Define, pronounce, and spell complementary terms related to the endocrine system.

19. Complementary Terms Built from Word Parts
endocrinopathy
euglycemia
euthyroid
glycemia
polydipsia
syndrome
adrenocorticohyperplasia
adrenopathy
cortical
corticoid
endocrinologist
endocrinology
What does the medical term polydipsia mean? What conditions are related to polydipsia?
Syndrome refers to signs and symptoms occurring together that are characteristic of a specific disorder.

20. Chapter 16
Objective 8: Interpret, read, and comprehend medical language in simulated medical statements, documents, and electronic health records.

21. Read Medical Terms in Use
A 55-year-old female patient presented to her doctor because of a 10-pound weight gain, fatigue, hair loss, dry skin, and cold intolerance. She was referred to an endocrinologist, who established a diagnosis of hypothyroidism after test results indicated an elevated thyroid-stimulating hormone (TSH) level and a low thyroxine level. Thyroid hormone therapy was prescribed.
Ask students to pronounce and define the bolded terms.

22. Read Medical Terms in Use (cont’d)
Approximately 20 years ago, she was diagnosed with Graves disease, characterized by hyperthyroidism, exophthalmos, fatigue, irritability, weight loss, and goiter. At this time, she had an increased radioactive iodine uptake (RAIU). Treatment included a thyroidectomy with subsequent thyroid hormone therapy.
Copyright © 2014, 2012, 2009, 2005, 2002, 1998, 1994, 1989, 1985 by Mosby, Inc., an affiliate of Elsevier Inc. All rights reserved.

23. Read Medical Terms in Use (cont’d)
She remained in a euthyroid state until she stopped taking the medication 6 months ago. Consequently, she became hypothyroid and could easily have developed myxedema if she had not sought treatment.
Copyright © 2014, 2012, 2009, 2005, 2002, 1998, 1994, 1989, 1985 by Mosby, Inc., an affiliate of Elsevier Inc. All rights reserved.