Excercise 27 Functional Anatomy of the Endocrine Glands Review Sheet 27 (Marieb)

1.  Both the endocrine and nervous systems are major regulating systems of the body; however, the nervous system has been compared to an airmail delivery system and the endocrine system to the Pony Express.  Briefly explain this comparison:

• The nervous system uses rapidly propagated electrical "messages"; whereas endocrine system "messages" (hormones) are liberated into the blood to travel much more slowly to the targeted organs.

2.  Define Hormone:  Chemical substance liberated into the blood, which alters"target cell" metabolism in a specific manner.

3.  Chemically, hormones belong chiefly to two molecular groups, the STEROIDS and the AMINO-ACID BASED MOLECULES.

4.  Define target organ:  Organ responding to a particular hormone in a specific way.

5.  If hormones travel in the bloodstream, why don't all tissues respond to all hormones?
The proper "hormone" receptors must be present on the plasma membrane or within the cells  for tissues to expand.

6.  Identify the endocrine organ described by each of the following statements:

Thyroid -  located in the throat; bilobed gland connected by an isthmus
Adrenal Gland - Found close to the kidney
Pancreas -  a mixed gland, located close to the stomach and small intestine
Testes - Paired glands suspended in the scrotum
parathyroids - ride "horseback" on the thyroid gland
ovaries - found in the pelvic cavity of the female, concerned with ova and female hormone production
thymus - found in the upper thorax overlying the heart; large during youth
pineal body - found in the roof of the third ventricle

7.  The table below lists the functions of many hormones you have studied.  From the keys below, fill in the hormones responsible for each function, and the endocrine glands that produce each hormone.  Glands may be used more than once.

FUNCTION                                                                          HORMONE                        GLANDS

Regulate the function of another endocrine gland                     TSH, FSH, ACTH, LH        Anterior pituitary
Maintenance of salt/water balance in the extracellular fluid        ADH -   Hypothalamus, Aldosterone - Adrenal   cortex
Directly involved/milk production and ejection                           Oxytocin - Hypothalamus, Prolactin - Anterior pituitary
Controls the rate of body metabolism and cellular oxidation     Thymosin - Thymus
Regulates blood calcium levels                                              Calcitonin - Parathyroid glands, PTH - thyroid
regulates blood glucose levels; produced by the same "mixed" gland     Glucagon, Insulin - Pancreas
released in response to stressors                                            Cortisone, Epinephrine - Adrenal cortex
drive development of secondary sex characteristics in males     Testosterone - Testes
directly responsible for regulation of the menstrual cycle       Estrogen, Progesterone - Ovaries


8.  Although the pituitary gland is often referred to as the master gland of the body, the hypothalamus exerts some control over the pituitary gland.  How does the hypothalamus control both the anterior and posterior pituitary functioning?
Produces "releasing and inhilating hormones", controls production and release of anterior pituitary hormones, forms hormones ADH/Oxytocin that are transported to the posterior pituitary and later released on nervous stimulation from the hypothalamus.

9. Indicate whether the release of hormones listed below is stimulated by A another hormone, B the nervous system; or C humoral factors.

     B  1.  ACTH
     C  2.  Calcitonin
     A  3.  Estrogens
     C. 4.  Insulin
     B  5.  Norepinephrine
     C  6.  Parathyroid hormone
     A  7.  T4/T3
     A  8.  testosterone
     B  9.  TSH, FSH

10.  Name the hormones produced in inadequate amounts that directly result in the following conditions.

Tetany - PTH
excessive diuresis without high blood glucose levels - ADH
loss of glucose in the urine - Insulin
abnormally small stature, normal proportions - growth hormone GH
Low BMR, mental and physical sluggishness - Thyroxine (T4)/ Triiodothyronine (T3 - thyroid hormone)
demineralization of bones spontaneous fractures - PTH

MICROSCOPIC ANATOMY OF SELECTED ENDOCRINE GLANDS

12.  Choose response from key:

A  1.  parafollicular cells of the thyroid (calcitonin)
H  2.  follicular epithelial cells of the thyroid (T4/T3)
E  3.  beta cells of the pancreatic islets (langerhorn) (insulin)
C  4.  Alpha cells of the pancreatic islets (langerhorn) ( glucagon)
I   5.  Basophil cells of the anterior pituitary (TSH, ACTH, FSH, LH)
D  6.  Zona fasciculata cells (glucocorticoids)
F  7.  Zona glomerulosa cells (mineralocorticoids)
G  8.  Chief cells of the parathyroid  (PTH)
B  9.  Acidophil cells of the anterior pituitary (GH, prolactin)

13.  Six diagrams of the microscopic structures of the endocrine glands are presented, identify each and name all structures indicated by a leader line or bracket.

A.  Anterior Pituitary (from left to right)  Basophils, Chromophobes, Acidophils
B.  Adrenal gland (Top to bottom)  Capsule, Zona glomerulosa, zona fascuculata, zona reticularis, adrenal   medulla
C.  Pancreatic Islet - Left to right - Exocrine tissue of the pancreas, Beta cells, Alpha Cells
D.  Thyroid gland - Left to right - Colloid-filled follicles, follicle cells, blood vessel
E.  Posterior pituitary - L to R - Fenestrated capillaries, ptuicytes
F.  Parathyroid Gland - L to R - Chief cells, oxyphil cells.