1. D-Endocrine System
Anatomy and Physiology
Chapter 13
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2. Chapter 13 Endocrine System
__________ glands are ductless
__________ glands have ducts
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3. Endocrine Glands Paracrine secretions Endocrine glands act locally
____________________
Endocrine glands
release hormones
______________ through blood to targets
Autocrine secretions
affect only the __________
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4. Comparison of Nervous System and Endocrine System
Neurons release neurotransmitters into a synapse, affecting postsynaptic cells
Glands release _______________ bloodstream
Only target of ________________
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5. Chemistry of Hormones Steroid Hormones Nonsteroid Hormones
derived from ___________
sex hormones
adrenal cortex hormones
Nonsteroid Hormones
amines
________
peptides
_____________
most hormones
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6. Structural Formulas of Hormones
13-6

7. Types of Hormones
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8. Actions of Steroid Hormones
hormone crosses membranes
hormone combines with receptor in nucleus
________________ activated
mRNA enters cytoplasm to direct synthesis of protein
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9. Actions of Nonsteroid Hormones
hormone binds to receptor on cell membrane
_____________________
ATP converted to cAMP
cAMP promotes a series of reactions leading to cellular changes
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10. Prostaglandins paracrine substances ___________ __________________
regulate cellular responses to hormones
can activate or inhibit adenylate cyclase
wide variety of functions
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11. Control of Hormonal Secretions
primarily controlled by negative feedback mechanism
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12. Negative Feedback
13-12

13. Major Endocrine Glands
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14. Pituitary Gland Two distinct portions
________________ (adenohypophysis)
__________________ (neurohypophysis)
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15. Pituitary Gland Control
Hypothalamic releasing hormones stimulate cells of anterior pituitary to release hormones
Nerve impulses from hypothalamus stimulate nerve endings in the posterior pituitary gland to release hormones
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16. Hypothalamic Hormones
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17. Anterior Pituitary Hormones
Growth Hormone (GH)
stimulates increase in size and rate of body cells
enhances movement of amino acids through membranes
promotes growth of long bones
______________________________
secretion stimulated by growth hormone-releasing hormone
Prolactin (PRL)
sustains milk production after birth
__________________________
secretion inhibited by prolactin release-inhibiting hormone
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18. Anterior Pituitary Hormones
__________________________________
controls secretions of hormones from the thyroid gland
controlled by thyrotropin-releasing hormone
Adrenocorticotropic Hormone
controls secretions of some hormones of adrenal cortex
_______________________-releasing hormone
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19. Anterior Pituitary Hormones
Follicle-Stimulating Hormone (FSH)
stimulates development of egg-containing follicles in ovaries
stimulates follicular cells to secrete estrogen
______________________________
controlled by gonadotropin-releasing hormone
_____________________
promotes secretions of sex hormones
________________________
promotes growth of long bones
_____________________________________
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20. Posterior Pituitary Hormones
Antidiuretic Hormone (ADH)
_________________________________
in high concentration, raises blood pressure
controlled by hypothalamus in response to changes in blood water concentration and blood volume
Oxytocin (OT)
stimulates uterine contractions
___________________________________
controlled by hypothalamus in response to stretch in uterine and vaginal walls and stimulation of breasts
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21. Thyroid Gland
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22. Thyroid Gland Hormones
Thyroxine (T4) and Triiodothyronine (T3)
________________________________ carbohydrates
increases rate of protein synthesis
accelerates growth
stimulates activity in the nervous system
__________________
Calcitonin
__________________ and phosphate ion concentrations by inhibiting release of calcium and phosphate from bones
increases rate at which calcium and phosphate are deposited in bones
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23. Thyroid Gland Disorders
General Hyperthyroidism
high metabolic rate
___________
weight loss
protruding eyes
Cretinism
______________ in infants
leads to small stature and mental retardation
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24. Thyroid Gland Disorders
Simple Goiter
deficiency of iodine
leads to deficiency of thyroid hormones
gland enlarges
Myxedema
________________
low metabolic rate
sluggishness
Grave’s disease
overstimulation of gland by antibodies
hyperthyroidism
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25. Parathyroid Glands
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26. Parathyroid Hormone PTH increases blood calcium levels
decreases blood phosphate levels
_________________________________
____________________
stimulates kidneys to retain calcium and excrete phosphate
promotes calcium absorption into intestine
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27. Parathyroid Glands
Mechanism by which PTH promotes calcium absorption in the intestine
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28. Parathyroid Gland Disorders
Hyperparathyroidism
caused by tumor
________
__________________
altered mental functions
bone weakening
Hypoparathyroidism
caused by injury or removal of gland
muscle cramps
seizures
_______________
levels
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29. Adrenal Glands
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30. Adrenal Medulla Hormones
______________________________
release controlled by sympathetic nervous system
increases heart rate and blood pressure
dilates respiratory airways
promotes breakdown of glycogen
activates reticular formation
__________________
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31. Adrenal Cortex Hormones
Aldosterone
_________________________ and pressure by promoting conservation of sodium ions and water
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32. Adrenal Cortex Hormones
Cortisol
_____________________________
increases fatty acid release
stimulates glucose synthesis from noncarbohydrates
controlled by _______________ and ACTH from anterior pituitary
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33. Adrenal Cortex Hormones
Adrenal androgens
supplement sex hormones from the gonads
__________________________
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34. Pancreas
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35. Pancreatic Hormones Glucagon
secreted by alpha cells of pancreatic islets
_________________________________________
stimulates liver to convert noncarbohydrates into glucose
stimulates break down of fats
controlled by blood glucose concentrations
Somatostatin
secreted by delta cells of pancreatic islets
___________________
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36. Pancreatic Hormones Insulin
secreted by beta cells of pancreatic islets
promotes formation of glycogen from glucose
inhibits conversion of noncarbohydrates into glucose
enhances movement of glucose into adipose and muscle cells
decreases blood glucose concentrations
_______________________________
_____________________________
____________________________________
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37. Insulin and Glucagon
Insulin and glucagon function together to stabilize blood glucose concentrations
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38. Other Endocrine Glands
Pineal Gland
secretes ___________
_______________________
may control onset of puberty
helps regulate female reproductive cycle
Thymus Gland
secretes thymosins
________________________________________
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39. Other Endocrine Glands
Reproductive Glands
_______ secrete estrogen and progesterone
______________________
placenta secretes estrogen, progesterone, and gonadotropins
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40. Stress Responses to Stress Types of Stress
hypothalamus triggers sympathetic impulses to various organs
epinephrine is released
cortisol is released to promote longer-term responses
Types of Stress
___________
________________
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41. Responses to Stress
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42. Life-Span Changes endocrine glands shrink
___ levels even out, muscular strength decreases
ADH levels increase due to slow break down
calcitonin levels decrease
_____ increases, osteoporosis risk increases
insulin resistance may develop
changes in melatonin secretion affect the body clock
thymosin production declines increasing risk of infections
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43. Clinical Application Growth Hormone Ups and Downs
__________ - hypersecretion of GH in children
Acromegaly – hypersecretion of GH in adults
___________ – hyposecretion of GH in children
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