5. Two regulatory mechanisms are involved in transmitting messages and overseeing various body functions.
These are:__a__and __b__ controls. __a__ controls are fast-acting and energetically expensive to operate
while __b__ controls are slow-acting and energetically inexpensive to operate.

14.  In the __a__ (many word answer) mechanism the hormone is carried by the blood and arrives at the __b__ cell. 
The hormone binds to a(n) __c__ in the __d__.  In this mechanism the hormone is referred to as the __e__.   The
hormone and __c__ have __f__ shapes and charges.  Binding causes an enzyme called __g__ to become active. 
__g__ breaks down ATP into __h__.  __h__ is called the __i__.  __h__ activates other enzymes called __j__ that
often phosphorylate and activate other __k__ in a biochemical pathway.  Since there are many kinds of __j__, __b__
cells can produce an wide array of __l__.  Additionally, only small quantities of a hormone are needed to produce
a measurable response by the __b__.  The pathway is turned off when __h__ is changed to __m__ by the enzyme __n__.

15.  In the __a__ (many word answer) mechanism, the hormone is carried by the blood to the __b__ cell,
but since the hormone is __c__ soluble, it diffuses through the __d__ into the __e__.  Once in the
__e__, the hormone binds with a __f__ forming the __g__.  This __g__ moves into the __h__
and binds to a __f__ on the __i__ molecule.  In this way, a polynucleotide section of the __i__,
called a(n) __j__ is activated directly.  The __j__ is transcribed and translated into a(n) __k__. 
This __k__ is probably a(n) __l__ that runs a biochemical pathway.

18. The pituitary, or __a__, is located in the __b__ of the __c__ bone.  It is attached to the
hypothalamus by a stalk called the __d__.  This gland is actually two glands, an anterior
portion called the __e__ and a posterior portion called the __f__.  The __e__ develops
as an outpocketing of the __g__ while the __f__ is a physical extension of the __h__.  

20.  The hypothalamus controls the activity of the anterior pituitary by __a__ and __b__ factors. 
__a__ factors stimulate the adenohypophysis while __b__ factors inhibit the adenohypophysis. 
These factors are delivered to the anterior pituitary by the __c__ system.

24.  The __a__ gland is located in front of the larynx at about the level between the 5th and 7th
vertebrae.  It is divided into __b__ (Number) lobes that are connected by a(n) __c__.  The gland
is organized into cellular hollow spheres called __d__.  Each __d__ is composed of cells
called __e__ cells and surround a lumen filled with __f__.  Cells found between the  __d__
are called __g__ cells. __g__ secrete the hormone __h__.
    __e__ cells have the ability to concentrate the ion __i__ 25-40 times above blood level.  This
__i__ will be used to make 2 of the 3 hormones produced by this gland.  __j__ is a protein,
composed of many __k__ (kind of amino acid), that  is synthesized by the rough endoplasmic
reticulum, transported to the __l__, and transported again by vesicles to the __m__.  In the
__m__  __j__ has __i__ ions attached, a process called __n__.  During __n__ , some __k__
receive one __i__ ion and others receive 2 __i__ ions.  Those amino acids with one ion are
called __o__ and those with 2 ions are called __p__.  While in the __m__ the __j__ coils
and loops allowing two __n__ __k__ to come in contact with each.  If two __p__ bond together,
__q__ is formed.  If a(n) __p__ and a(n)__o__ bond together, __r__ is formed.  Notice that at
this point in the synthesis both __q__ and __r__ are still part of the protein __j__.  The __n__ 
__j__ is now brought into the __e__ cells by a process called __s__.  Enzymes found in a __t__
(give organelle) merge with the incoming vesicle and cleave off __q__ and __r__.  Both
hormones diffuse out of the __e__ cell into the __u__ where they are picked up by a transport
protein called __v__.  Once arriving at the target cell, both diffuse into the cytoplasm through
the plasma membrane.  In the cytoplasm most of the less active form, __w__, is converted to the
most active form, __x__.

25.  The __a__ glands are paired masses of tissue embedded in the dorsal surface of the thyroid
gland. There are two  kinds of cells present, __b__ cells which secrete __c__ and __d__, cells
of unknown function. __c__ is released in response to __e__ (high/low) __f__  levels.    

27.  The __a__ gland is located superior to the kidneys and is actually two glands.  One is
derived from neuroectoderm and is called the __b__.  The __b__ secretes __c__ (Name
both hormones.).  This gland is found in/on the __d__ (middle/periphery).   The other gland
 is derived from __e__ (ectoderm/ mesoderm/endoderm) and secretes nearly 50 different
hormones divided into 3 broad categories:  __f__, __g__, and __h__.  Aldosterone is a(n)
__f__, cortisol is a(n) __g__, and estrogen is a(n) __h__.

49.  A hormone is released into the blood stream and distributed to various target structures by the circulation.  A secondary messenger is formed as the result of a hormone binding to a receptor on a target cell.  Once the secondary messenger is activated or formed, it causes the physiological change inside the target cell.
50. In negative feedback the body's response is opposite to the stimulus.  For example, in the parathyroid glands receptors detect low Ca++ levels in the blood.  Low Ca++ levels is the trigger that causes parathyroid cells to increase manufacture of PTH.  PTH affects various body organs (the bones, kidneys, GI tract) which raises the  amount  of Ca++ in the blood.  Receptors in the parathyroid glands detect these elevated Ca++ levels and inhibit production of PTH.
51. The design of the hypothalamo-hypophyseal portal system is such that it transports releasing and inhibiting factors directly from the hypothalamus to the anterior pituitary.  If these factors had to make the entire circulatory circuit back to the pituitary, much higher levels of the releasing and inhibiting factors would be required and the result would be slower.
52. Both giantism and acromegaly are the result of increased production of GH.  Giantism results when a child receives too much GH.  If the epiphyseal plates have not closed, the child can grow very tall.  Acromegaly results when an adult receives too much GH.  Since the epiphyseal plates are closed, no further growth in height can occur, but the soft cartilage tissues of the hands, face, and vertebrae are still affected resulting in the distortion of body features.
53. Diabetes mellitus is caused by a deficiency of insulin while diabetes insipidus is caused by a deficiency of ADH.  Both disorders result in polyuria and polydipsia, but only diabetes mellitus patients will exhibit polyphagia because lack of insulin prevents glucose from moving into cells and much of the glucose is lost during urination.  Diabetes insipidus patients still have proper amounts of insulin and their cells do not starve.  These patients lose water because ADH hormone causes water reabsorption by the kidney tubules. Lack of ADH allows large amounts of water to leave with the urine.  Increased water loss of course results in increased thirst.
54. Partially answered in #53, but in diabetes mellitus patients the loss of glucose in the urine osmotically draws out large quantities of water.  Lowered insulin levels result in increased glucose loss, followed by increased water losses, followed by increased thirst to replaced the lost water and increased hunger in a feeble attempt to feed the body's starving cells.
55. Excessive amounts of GH cause increased blood glucose levels because glycogen stores are broken down.  GH causes increased use of fatty acids for energy instead of glucose. Blood glucose levels therefore elevate and eventually burn out the beta cells of the pancreas.
56.  Secondary hyperthyroidism.  Assuming the tumor caused increased release of TSH, the thyroid gland would release more than normal amounts of thyroid hormones and elevate metabolism.  Symptoms would be similar to Grave's disease.
57. Secondary hypothyroidism. If TRH causes the anterior pituitary to release more TSH that causes increased production of thyroid hormone from the thyroid gland, then lowered levels of TRH will indirectly cause lowered production of thyroid hormones.  Since the hypothyroidism is not a direct result of thyroid gland malfunction the disorder is called secondary hypothyroidism.
58. If you had given the patient TSH and his hypothyroidism did not improve it would mean his thyroid gland is not working properly.  But since giving TSH gave rapid improvement in the patient's condition, the condition must be a secondary hypothyroidism involving the anterior pituitary.
59. In hypoaldosteronism, too much Na+ is lost and too much K+ is retained while in hyperaldosteronism the reverse is true.  Therefore, aldosterone affects Na+ and indirectly K+ levels.  Since these are the two key ions in maintaining a polarized membrane, an imbalance of either would affect nerve impulse transmission.  
60. In Addison's disease the adrenal cortex is not responding to ACTH from the anterior pituitary.  The anterior pituitary therefore releases more ACTH in a hopeless attempt to maintain homeostasis.  Since ACTH is a chemical mimic of MSH, the melanocytes respond to the higher levels and dramatically darken the patient's skin.
61. Prior to menopause elevated estogen levels completely mask the effects of testosterone released by the zona reticularis of the adrenal cortex.  With declining estrogen levels after menopause the testosterone is not so masked and some hair follicles are stimulated to grow.
62. Clearly this man has a lot of stress in his life which is causing elevated levels of glucocorticoids from his adrenal cortex.  Glucocorticoids cause protein catabolism from his muscle tissue resulting in muscular weakness and cause increased glycogen formation and gluconeogenesis which raises blood glucose to almost diabetic levels.  His increased urination is a result of his near diabetic state.
63. Receptor types different on each target cell.  Hormone matches receptor type so that only the correct cells are affected.
64.  Because each cell has its own contingent of protein kinases that affect a variety of metabolic pathways, a cell can make completely opposing responses to the same hormone.