Maryville University Patho NURS 611 Exam 3 QUESTIONS AND ANSWERS Patho NURS
611 Exam 3
Questions
and
Answers
1. What are clinical manifestations of hypothyroidism?
a. Intolerance to heat, tachycardia, and weight loss
b. Oligomenorrhea, fatigue, and warm skin
c. Restlessness, increased appetite, and metrorrhagia
d. Constipation, decreased heat rate, and lethargy
The lower levels of thyroid hormone result in decreased energy metabolism, resulting
in constipation, bradycardia, and lethargy, thus eliminating the remaining options.
2. Thyroid-stimulating hormone (TSH) is released to stimulate thyroid hormone (TH) and is
inhibited when plasma levels of TH are adequate. This is an example of:
a. Positive feedback
b. Neural regulation
c. Negative feedback
d. Physiologic regulation
Negative feedback. Feedback systems provide precise monitoring and control of the
cellular environment. Negative feedback occurs because the changing chemical, neural,
or endocrine response to a stimulus negates the initiating change that triggered the
release of the hormone. Thyrotropin-releasing hormone (TRH) from the hypothalamus
stimulates TSH secretion from the anterior pituitary. Secretion of TSH stimulates the
synthesis and secretion of THs. Increasing levels of T
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and triiodothyronine (T
) then
generate negative feedback on the pituitary and hypothalamus to inhibit TRH and TSH
synthesis.
3. Lipid-soluble hormone receptors are located:
a. Inside the plasma membrane in the cytoplasm
b. On the outer surface of the plasma membrane
c. Inside the mitochondria
d. On the inner surface of the plasma membrane
Inside the plasma membrane in the cytoplasm. Lipid-soluble hormone receptors are
located inside the plasma membrane and easily diffuse across the plasma membrane to
bind to either cytosolic or nuclear receptors.
4. The releasing hormones that are made in the hypothalamus travel to the anterior
pituitary via the:
a. Vessels of the zona fasciculata
b. Hypophyseal stalk
c. Infundibular stem
d. Portal hypophyseal blood vessels
Portal hypophyseal blood vessels. Releasing and inhibitory hormones are synthesized in
the hypothalamus and are secreted into the portal blood vessels through which they
travel to the anterior pituitary hormones.
5. Which mineral is needed for thyroid-stimulating hormone (TSH) to stimulate the
secretion of thyroid hormone (TH)?
a. Iron
b. Iodide
c. Zinc
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d. Copper
Iodide. TSH, which is synthesized and stored in the anterior pituitary, stimulates
secretion of TH by activating intracellular processes, including the uptake of iodine
necessary for the synthesis of TH.
6. What effect does hyperphosphatemia have on other electrolytes?
a. Increases serum calcium
b. Decreases serum magnesium
c. Decreases serum calcium
d. Increases serum magnesium
Decreases serum calcium. Hyperphosphatemia leads to hypocalcemia. Remember that
phos and calcium are inversely related.
7. Insulin transports which electrolyte in the cell?
a. Potassium
b. Sodium
c. Calcium
d. Phosphorus
Potassium. Insulin facilitates the intracellular transport of potassium, phosphate, and
magnesium.
8. Which second messenger is stimulated by epinephrine binding to a β-adrenergic
receptor?
a. Calcium
b. Inositol triphosphate (IP
)
c. Diacylglycerol (DAG)
d. Cyclic adenosine monophosphate (cAMP)
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Cyclic adenosine monophosphate (cAMP). Second-messenger molecules are the initial
link between the first signal (hormone) and the inside of the cell. For example, the
binding of epinephrine to a β adrenergic–receptor subtype activates (through a
stimulatory G protein) the enzyme, adenylyl cyclase. Adenylyl cyclase catalyzes the
conversion of adenosine triphosphate (ATP) to the second messenger, 3', and 5'-cAMP.
9. Regulation of the release of catecholamines from the adrenal medulla is an example of
which type of regulation?
a. Negative feedback
b. Neural
c. Positive feedback
d. Physiologic
Neural. The release of hormones occurs either in response to an alteration in the cellular
environment or in the process of maintaining a regulated level of certain hormones or certain
substances. Several different mechanisms, one of which is neural control (e.g., stress-induced
release of catecholamines from the adrenal medulla), regulate the release of hormones.
10. Which hormone does the second messenger calcium (Ca
++
) bind to activate
phospholipase C through a G protein?
a. Angiotensin II
b. Estrogen
c. Thyroxine
2
d. Testosterone
Angiotensin II. Ca
++
is considered an important second messenger that facilitates the
binding of a hormone (e.g., norepinephrine, angiotensin II) to a surface receptor,
activating the enzyme phospholipase C through a G protein inside the plasma
membrane.
11. The control of calcium in cells is important because it:
a. Is controlled by the calcium negative-feedback loop.
b. Is continuously synthesized.
c. Acts as a second messenger.
d. Carries lipid-soluble hormones in the bloodstream.
Acts as a second messenger. In addition to being an important ion that participates in a
multitude of cellular actions, Ca
++
is considered an important second messenger.
12. Where is antidiuretic hormone (ADH) synthesized, and where does it act?
a. Hypothalamus; renal tubular cells
b. Anterior pituitary; posterior pituitary
c. Renal tubules; renal collecting ducts
d. Posterior pituitary; loop of Henle
Hypothalamus; renal tubular cells. Once synthesized in the hypothalamus, ADH acts on
the vasopressin 2 (V2) receptors of the renal duct cells to increase their permeability.
13. How does a faulty negative-feedback mechanism result in a hormonal imbalance?
a. Hormones are not synthesized in response to cellular and tissue activities.
b. Decreased hormonal secretion is a response to rising hormone levels.
c. Too little hormone production is initiated.
d. Excessive hormone production results from a failure to turn of the system.
Excessive hormone production results from a failure to turn off the system. Negativefeedback
systems
are
important
in
maintaining
hormones
within
physiologic
ranges.
The
lack
of
negative-feedback
inhibition
on
hormonal
release
often
results
in
pathologic
conditions.
Excessive
hormone
production,
which
is
the
result
of
the
failure
to
turn
of
the
system,
can
cause
various
hormonal
imbalances
and
related
conditions.
14. A deficiency of which chemical may result in hypothyroidism?
a. Iron
b. Zinc
c. Iodine
d. Magnesium
Zinc. The only cause of hypothyroidism from among the provided options is a deficiency
of endemic iodine.
15. What imbalance lessens the rate of secretion of parathyroid hormone
a. Increased serum calcium levels
b. Decreased serum magnesium levels
c. Decreased levels of thyroid-stimulating hormone
d. Increased levels of thyroid-stimulating hormone
The overall effect of parathyroid hormone (PTH)is to increase serum calcium and to
decrease serum phosphate concentration.
16. Which condition may result from pressure exerted by a pituitary tumor?
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a. Hypothyroidism
b. Diabetes insipidus
c. Hypercortisolism
d. Insulin hyposecretion
Hypothyroidism. If the tumor exerts sufficient pressure, then thyroid and adrenal
hypofunction may occur because of lack of thyroid-stimulating hormone (TSH) and
adrenocorticotropic hormone (ACTH). These result in the symptoms of hypothyroidism
and hypocortisolism.
17. Which substance is a water-soluble protein hormone?
a. Thyroxine
b. Follicle-stimulating hormone
c. Aldosterone
d. Insulin
Insulin. Peptide or protein hormones, such as insulin, pituitary, hypothalamic, and
parathyroid, are water soluble and circulate in free (unbound) forms.
18. Which of the following is a lipid-soluble hormone?
a. Cortisol
b. Epinephrine
c. Oxytocin
d. Growth hormone
Cortisol. Cortisol and adrenal androgens are lipid-soluble hormones and are primarily
bound to a carrier or transport protein in circulation.
19. Most protein hormones are transported in the bloodstream and are:
a. Bound to a lipid-soluble carrier
b. Free in an unbound, water-soluble form
c. Bound to a water soluble–binding protein
d. Free because of their lipid-soluble chemistry
Free in an unbound, water-soluble form. Peptide or protein hormones, such as insulin,
pituitary, hypothalamic, and parathyroid, are water soluble and circulate in free
(unbound) forms.
20. When insulin binds its receptors on muscle cells, an increase in glucose uptake by the
muscle cells is the result. This is an example of what type of effect by a hormone?
a. Pharmacologic
b. Synergistic
c. Permissive
d. Direct
Direct. Direct effects are the obvious changes in cell function that specifically result from
the stimulation by a particular hormone.
21. Graves disease develops from a(n):
a. Viral infection of the thyroid gland that causes overproduction of thyroid
hormone.
b. Autoimmune process during which lymphocytes and fibrous tissue replace
thyroid tissue.
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c. Thyroid-stimulating immunoglobulin that causes overproduction of thyroid
hormones.
d. Ingestion of goitrogens that inhibits the synthesis of the thyroid hormones,
causing a goiter.
Thyroid-stimulating immunoglobulin that causes the overproduction of thyroid
hormones. The pathologic features of Graves disease indicates that normal regulatory
mechanisms are overridden by abnormal immunologic mechanisms that result in the
stimulation of excessive TH.
22. Pathologic changes associated with Graves disease include:
a. High levels of circulating thyroid-stimulating immunoglobulins
b. Diminished levels of thyrotropin-releasing hormone
c. High levels of thyroid-stimulating hormone
d. Diminished levels of thyroid-binding globulin
High levels of circulating thyroid-stimulating immunoglobulins. The only option that
correctly describes the changes associated with Graves disease identifies high levels of
circulating thyroid-stimulating immunoglobulins that are found in more than 95% of
individuals diagnosed with the disease.
23. The signs of thyrotoxic crisis include:
a. Constipation with gastric distention
b. Hyperthermia and tachycardia
c. Bradycardia and bradypnea
d. Constipation and lethargy
Hyperthermia and tachycardia
24. The level of thyroid-stimulating hormone (TSH) in individuals with Graves disease is
usually:
a. High
b. Normal
c. Low
d. In constant flux
Low. The hyperfunction of the thyroid gland leads to suppression of TSH because of the
normal negative feedback mechanism.
25. Palpation of the neck of a person diagnosed with Graves disease would detect a thyroid
that is:
a. Left of midline
b. Normal in size
c. Small with discrete nodules
d. Diffusely enlarged
Diffusely enlarged.
26. The effects of the syndrome of inappropriate antidiuretic hormone (SIADH) secretion
include solute:
a. Retention and water retention
b. Dilution and water retention
c. Retention and water loss
d. Dilution and water loss
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Retention and water loss
27. The common cause of elevated levels of antidiuretic hormone (ADH) secretion is:
a. Ectopically produced ADH
b. Posterior pituitary tumor
c. Inflammation of the hypothalamus
d. Inflammation of the nephrons
Ectopically produced ADH
28. Which laboratory value would the nurse expect to find if a person is experiencing
syndrome of inappropriate antidiuretic hormone (SIADH)?
a. Hypernatremia and urine hypo-osmolality
b. Serum potassium (K
+
) level of 5 mEq/L and urine hyper-osmolality
c. Serum sodium (Na
+
) level of 120 mEq/L and serum hypo-osmolality
d. Hypokalemia and serum hyper-osmolality
Serum Na level of 120 and serum hypo-osmolatlity. A diagnosis of SIADH requires a
serum sodium level of less than 135 mEq/L, serum hypo-osmolality less than 280
mOsm/kg, and urine hyper-osmolarity. Potassium levels are not considered a factor.
29. A patient who is diagnosed with a closed head injury has a urine output of 6 to 8 L/day.
Electrolytes are within normal limits, but his antidiuretic hormone (ADH) level is low.
Although he has had no intake for 4 hours, no change in his polyuria level has occurred.
These symptoms support a diagnosis of:
a. Neurogenic diabetes insipidus
b. Syndrome of inappropriate antidiuretic hormone
c. Psychogenic polydipsia
d. Osmotically induced diuresis
Neurogenic diabetes insipidus. Remember, sodium has to be below 135 to meet the
requirement for SIADH.
30. Diabetes insipidus, diabetes mellitus, and syndrome of inappropriate antidiuretic
hormone all exhibit which symptom?
a. Polyuria
b. Vomiting
c. Edema
d. Thirst
Thirst, is the only symptom in common.
31. The cause of neurogenic diabetes insipidus (DI) is related to an organic
a. Anterior pituitary
b. Posterior pituitary
c. Thalamus
d. Renal tubules
Posterior pituitary. Neurogenic DI is a result of dysfunctional antidiuretic hormone
synthesis, caused by a lesion of the posterior pituitary, hypothalamus, or pituitary stalk.
32. Which form of diabetic insipidus (DI) will result if the target cells for antidiuretic
hormone (ADH) in the renal collecting tubules demonstrate insensitivity?
a. Neurogenic
b. Nephrogenic
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c. Psychogenic
d. Ischemic
Nephrogenic. Only nephrogenic DI is associated with an insensitivity of the renal
collecting tubules to ADH.
33. Which laboratory value is consistently low in a patient with diabetes insipidus (DI)?
a. Urine-specific gravity
b. Urine protein
c. Serum sodium
d. Serum total protein
Urine-specific gravity. The basic criteria for diagnosing DI include a low urine-specific
gravity while sodium levels are high. Protein levels are not considered.
34. Which form of diabetes insipidus (DI) is treatable with exogenous antidiuretic hormone
(ADH)?
a. Neurogenic
b. Nephrogenic
c. Psychogenic
d. Ischemic
Neurogenic DI is treated with ADH replacement therapy.
35. The term used to describe a person who experiences a lack of all hormones associated
with the anterior pituitary is:
a. Panhypopituitarism
b. Hypopituitarism
c. Adrenocorticotropic hormone deficiency
Panhypopituitarism is the only available term that is correctly associated with the lack of
all anterior pituitary hormones.
36. Diabetes insipidus is a result of:
a. Antidiuretic hormone hyposecretion
b. Insulin hyposecretion
c. Antidiuretic hormone hypersecretion
d. Insulin hypersecretion
ADH hyposecretion
37. Visual disturbances are a result of a pituitary adenoma because of the:
a. Liberation of anterior pituitary hormones into the optic chiasm
b. Pituitary hormones clouding the lens of the eyes
c. Pressure of the tumor on the optic chiasm
d. Pressure of the tumor on the optic and oculomotor cranial nerves
Pressure on the optic chiasm is the only cause for visual disturbances resulting from a
pituitary adenoma.
38. Which hormone is involved in the regulation of serum calcium levels?
a. Parathyroid hormone (PTH)
b. Thyroxine (T
)
c. Adrenocorticotropic hormone (ACTH)
d. Triiodothyronine (T
4
)
The parathyroid glands produce PTH, a regulator of serum calcium.
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7
39. Target cells for parathyroid hormone are located in the:
a. Tubules of nephrons
b. Glomeruli of nephrons
c. Thyroid gland
d. Smooth and skeletal muscles
Tubules of nephrons. Parathyroid hormone acts on its plasma membrane receptor only
in the distal and proximal tubules of the kidney’s nephron.
40. Renal failure is the most common cause of which type of hyperparathyroidism?
a. Primary
b. Exogenous
c. Secondary
d. Inflammatory
Secondary. Chronic renal failure is the most common cause of secondary
hyperparathyroidism because of the resulting hyperphosphatemia that stimulates
parathyroid hormone secretion. Although the other options may occur, they are not the
most common types of the disorder.
41. The most common cause of hypoparathyroidism is:
a. Pituitary hyposecretion
b. Parathyroid gland damage
c. Parathyroid adenoma
d. Autoimmune parathyroid disease
Parathyroid gland damage. The most common cause of hypoparathyroidism is damage
caused during thyroid surgery.
42. The most probable cause of low serum calcium after a thyroidectomy is:
a. Hyperparathyroidism, secondary to Graves disease
b. Myxedema, secondary to surgery
c. Hypoparathyroidism caused by surgical injury
d. Hypothyroidism caused by the lack of thyroid replacement
The most common cause of hypoparathyroidism is damage caused during thyroid
surgery, resulting in a lack of circulating PTH and causing a depressed level of serum
calcium.
43. A patient diagnosed with diabetic ketoacidosis (DKA) has the following laboratory values:
arterial pH 7.20; serum glucose 500 mg/dl; positive urine glucose and ketones; serum
potassium (K
+
) 2 mEq/L; serum sodium (Na
+
) 130 mEq/L. The patient reports that he has
been sick with the “flu” for 1 week. What relationship do these values have to his insulin
deficiency?
a. Increased glucose use causes the shift of fluid from the intravascular to the
intracellular space.
b. Decreased glucose use causes fatty acid use, ketogenesis, metabolic acidosis, and
osmotic diuresis.
c. Increased glucose and fatty acids stimulate renal diuresis, electrolyte loss, and
metabolic alkalosis.
d. Decreased glucose use results in protein catabolism, tissue wasting, respiratory
acidosis, and electrolyte loss.
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Decreased glucose causes fatty acid use, ketogenesis, metabolic acidosis, and osmotic
diuresis, which have resulted in the symptoms listed in the question.
44. Polyuria occurs with diabetes mellitus because of the:
a. Formation of ketones
b. Elevation in serum glucose
c. Chronic insulin resistance
d. Increase in antidiuretic hormone
Elevation of serum glucose. Glucose accumulates in the blood and appears in the urine
as the renal threshold for glucose is exceeded, producing an osmotic diuresis and the
symptoms of polyuria and thirst.
45. Type 2 diabetes mellitus is best described as a(an):
a. Resistance to insulin by insulin-sensitive tissues
b. Need for lispro instead of regular insulin
c. Increase of glucagon secretion from α cells of the pancreas
d. Presence of insulin autoantibodies that destroy β cells in the pancreas
Resistance to insulin by insulin-sensitive tissues. One of the basic pathophysiologic
characteristics of type 2 diabetes is the development of insulin-resistant tissue cells.
46. A person diagnosed with type 1 diabetes experiences hunger, lightheadedness,
tachycardia, pallor, headache, and confusion. The most probable cause of these
symptoms is:
a. Hyperglycemia caused by incorrect insulin administration
b. Dawn phenomenon from eating a snack before bedtime
c. Hypoglycemia caused by increased exercise
d. Somogyi effect from insulin sensitivity
Hypoglycemia caused by increased exercise. The most likely cause of these symptoms is
hypoglycemia, which is often caused by a lack of systemic glucose as a result of
muscular activity.
47. When comparing the clinical manifestations of both diabetic ketoacidosis (DKA) and
hyperglycemic hyperosmolar nonketotic syndrome (HHNKS), which condition is
associated with only DKA?
a. Fluid loss
b. Increased serum glucose
c. Weight loss
d. Kussmaul respirations
Kussmaul respirations are only observed in those with DKA and is that “air hunger” or
rapid deep labored breathing.
48. Hypoglycemia, followed by rebound hyperglycemia, is observed in those with:
a. The Somogyi effect
b. The dawn phenomenon
c. Diabetic ketoacidosis
d. Hyperosmolar hyperglycemic non-ketotic syndrome
Hypoglycemia, followed by rebound hyperglycemia, is observed only in the Somogyi
effect.
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