MARYVILLE NURS 611 EXAM 3 UPDATE COMPREHENSIVE QUESTIONS AND VERIFIED SOLUTIONS 2025

What are clinical manifestations of hypothyroidism? - -Constipation, decreased heat rate, and lethargy 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: - -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. Lipid-soluble hormone receptors are located: - -Inside the plasma membrane in the cytoplasm. The releasing hormones that are made in the hypothalamus travel to the anterior pituitary via the: - -Portal hypophyseal blood vessels. Which mineral is needed for thyroid-stimulating hormone (TSH) to stimulate the secretion of thyroid hormone (TH)? - -Iodide. What effect does hyperphosphatemia have on other electrolytes? - -Decreases serum calcium. Insulin transports which electrolyte in the cell? - -Potassium. Which second messenger is stimulated by epinephrine binding to a β-adrenergic receptor? - -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. Regulation of the release of catecholamines from the adrenal medulla is an example of which type of regulation? - -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 NURS 611 NURS 611 which is neural control (e.g., stress-induced release of catecholamines from the adrenal medulla), regulate the release of hormones. Which hormone does the second messenger calcium (Ca++) bind to activate phospholipase C through a G protein? - -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. The control of calcium in cells is important because it: - -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. Where is antidiuretic hormone (ADH) synthesized, and where does it act? - 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. How does a faulty negative-feedback mechanism result in a hormonal imbalance? - Excessive hormone production results from a failure to turn off the system. Negative- feedback 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 off the system, can cause various hormonal imbalances and related conditions. A deficiency of which chemical may result in hypothyroidism? - -Iodine. The only cause of hypothyroidism from among the provided options is a deficiency of endemic iodine. What imbalance lessens the rate of secretion of parathyroid hormone - -The overall effect of parathyroid hormone (PTH)is to increase serum calcium and to decrease serum phosphate concentration. Which condition may result from pressure exerted by a pituitary tumor? - 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. Which substance is a water-soluble protein hormone? - -Insulin. Peptide or protein hormones, such as insulin, pituitary, hypothalamic, and parathyroid, are water soluble and circulate in free (unbound) forms. Which of the following is a lipid-soluble hormone? - -Cortisol. Cortisol and adrenal androgens are lipid-soluble hormones and are primarily bound to a carrier or transport protein in circulation. NURS 611 NURS 611 Most protein hormones are transported in the bloodstream and are: - -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. 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? - Direct. Direct effects are the obvious changes in cell function that specifically result from the stimulation by a particular hormone. Graves disease develops from a(n): - -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. Pathologic changes associated with Graves disease include: - -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. The signs of thyrotoxic crisis include: - -Hyperthermia and tachycardia The level of thyroid-stimulating hormone (TSH) in individuals with Graves disease is usually: - -Low. The hyperfunction of the thyroid gland leads to suppression of TSH because of the normal negative feedback mechanism. Palpation of the neck of a person diagnosed with Graves disease would detect a thyroid that is: - -Diffusely enlarged. The effects of the syndrome of inappropriate antidiuretic hormone (SIADH) secretion include solute: - -Dilution & water retention The common cause of elevated levels of antidiuretic hormone (ADH) secretion is: - Ectopically produced ADH Which laboratory value would the nurse expect to find if a person is experiencing syndrome of inappropriate antidiuretic hormone (SIADH)? - -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. 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: - -Neurogenic diabetes insipidus. Remember, sodium has to be below 135 to meet the requirement for SIADH. NURS 611 NURS 611 Diabetes insipidus, diabetes mellitus, and syndrome of inappropriate antidiuretic hormone all exhibit which symptom? - -Thirst, is the only symptom in common. The cause of neurogenic diabetes insipidus (DI) is related to an organic - -Posterior pituitary. Neurogenic DI is a result of dysfunctional antidiuretic hormone synthesis, caused by a lesion of the posterior pituitary, hypothalamus, or pituitary stalk. Which form of diabetic insipidus (DI) will result if the target cells for antidiuretic hormone (ADH) in the renal collecting tubules demonstrate insensitivity? - -Nephrogenic. Only nephrogenic DI is associated with an insensitivity of the renal collecting tubules to ADH. Which laboratory value is consistently low in a patient with diabetes insipidus (DI)? - 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. Which form of diabetes insipidus (DI) is treatable with exogenous antidiuretic hormone (ADH)? - -Neurogenic DI is treated with ADH replacement therapy. The term used to describe a person who experiences a lack of all hormones associated with the anterior pituitary is: - -Panhypopituitarism is the only available term that is correctly associated with the lack of all anterior pituitary hormones. Diabetes insipidus is a result of: - -ADH hyposecretion Visual disturbances are a result of a pituitary adenoma because of the: - -Pressure on the optic chiasm is the only cause for visual disturbances resulting from a pituitary adenoma. Which hormone is involved in the regulation of serum calcium levels? - -The parathyroid glands produce PTH, a regulator of serum calcium. Target cells for parathyroid hormone are located in the: - -Tubules of nephrons. Parathyroid hormone acts on its plasma membrane receptor only in the distal and proximal tubules of the kidney's nephron. Renal failure is the most common cause of which type of hyperparathyroidism? - 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. The most common cause of hypoparathyroidism is: - -Parathyroid gland damage. The most common cause of hypoparathyroidism is damage caused during thyroid surgery. NURS 611 NURS 611 The most probable cause of low serum calcium after a thyroidectomy is: - -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. 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