NUR 4135 PrepU Chapter 40
Which statement best explains the function of hormone receptors? - Hormone receptors produce antibodies to block certain hormones from entering the cell. - Hormone receptors respond to decreasing hormone levels by producing a decrease in receptor numbers. - Hormone receptors recognize a specific hormone and translate the hormonal signal into a cellular response. - Hormone receptors are located within the red blood cells and carry hormones to the target cells.
Hormone receptors recognize a specific hormone and translate the hormonal signal into a cellular response. Explanation: Hormone receptors are complex molecular structures that are located either on the surface of or inside target cells. The function of these receptors is to recognize a specific hormone and translate the hormonal signal into a cellular response.
Cyclic adenosine monophosphate (cAMP) performs which role in the functioning of the endocrine system? Acting as a high-affinity receptor on the surface of target cells Mediating hormone synthesis by non-vesicle-mediated pathways Inactivating hormones to prevent excess accumulation Acting as a second messenger to mediate hormone action on target cells
Acting as a second messenger to mediate hormone action on target cells Explanation: cAMP is one of the most common second messengers, whose role is to generate an intracellular signal in response to cell surface receptor activation by a hormone. cAMP does not mediate hormone synthesis, act as a receptor itself, or inactivate hormones.
When hormones act locally rather than being secreted into the bloodstream, their actions are termed: Preventers and inhibitors Localized and influential Autocrine and paracrine Autocratic and paracratic
Autocrine and paracrine Explanation: When hormones act locally on cells other than those that produced the hormone, the action is called paracrine. Hormones also can exert an autocrine action on the cells from which they were produced.
To prevent the accumulation of hormones in our bodies, the hormones are constantly being metabolized and excreted. Where are adrenal and gonadal steroid hormones excreted? Bile and urine Cell metabolites and lungs Feces and urine Bile and lungs
Bile and urine Explanation: Unbound adrenal and gonadal steroid hormones are conjugated in the liver, which renders them inactive, and then excreted in the bile or urine. Adrenal and gonadal steroid hormones are not excreted in the feces, cell metabolites, or the lungs.
The nurse is planning to collect a 24-hour urine sample for hormone assay. In which situation does the nurse collaborate with the health care provider to find an alternate type of testing? Client has anemia. Client has anuria. Client has hypothyroidism. Client has diabetes.
Client has anuria. Explanation: The advantages of a urine test include the relative ease of obtaining urine samples and the fact that blood sampling is not required. The disadvantage is that reliably timed urine collections often are difficult to obtain and rely on adequate renal function. Anuria refers to the absence of urine output.
Which gland acts as a signal relaying bridge between multiple body systems and the pituitary gland? Parathyroid Hypothalamus Thyroid Posterior pituitary
Hypothalamus Explanation: The activity of the hypothalamus is regulated by both hormonally mediated signals (e.g., negative feedback signals) and by neuronal input from a number of sources. Neuronal signals are mediated by neurotransmitters such as acetylcholine, dopamine, norepinephrine, serotonin, gamma-aminobutyric acid (GABA), and opioids. Cytokines that are involved in immune and inflammatory responses, such as the interleukins, also are involved in the regulation of hypothalamic function. This is particularly true of the hormones involved in the hypothalamic-pituitary-adrenal axis. Thus, the hypothalamus can be viewed as a bridge by which signals from multiple systems are relayed to the pituitary gland. This cannot be said of the other options.
A health care provider is assessing a client for a potential endocrine disorder. Assessment findings identify abnormalities with emotion, pain, and body temperature. Which mechanism of endocrine control will require further laboratory/diagnostic assessment? Cerebral cortex Cerebellum Anterior pituitary Hypothalamus
Hypothalamus Explanation: The hypothalamus is the coordinating center of the brain for endocrine, behavioral, and autonomic nervous system function. It is at the level of the hypothalamus that emotion, pain, body temperature, and other neural input are communicated to the endocrine system. The anterior pituitary regulates several physiologic processes, including stress, growth, reproduction, and lactation. The cerebellum is involved in motor control, and the cerebral cortex is associated with sensory, motor, and association.
An infant whose mother had myxedema during the pregnancy has failed to meet standards for growth and is developmentally delayed. Which hormonal imbalance is this child exhibiting? Calcium insufficiency Hypoglycemia Hypothyroidism Dopamine insufficiency
Hypothyroidism Explanation: Thyroid hormone is necessary for metabolism at all ages, as well as growth and development during childhood. Uncorrected thyroid insufficiency in childhood leads to cretinism, a condition with marked physical and intellectual disability. Myxedema is the term used for thyroid insufficiency in adults.
A nursing instructor is teaching a group of students about the action of hormones. The instructor determined that teaching was effective when the students recognize the local action of hormones as: Autocrine Hormonal Pancreatic Paracrine
Paracrine Explanation: When hormones act locally on cells other than those that produced the hormone, the action is called paracrine. Hormones can also exert an autocrine action on the cells in which they were produced. Pancreatic and hormonal are not actions.
Which statement best describes the relationship between the hypothalamus and the posterior pituitary in the normal functioning of the endocrine system? Posterior pituitary hormones are produced in the cell bodies of neurons in the hypothalamus but released from the pituitary gland. Posterior pituitary hormones are constituted from components of both the hypothalamus and the pituitary gland itself. The hypothalamus regulates the production and release of posterior pituitary hormones by the pituitary gland. The posterior pituitary gland regulates the release of hypothalamic hormones.
Posterior pituitary hormones are produced in the cell bodies of neurons in the hypothalamus but released from the pituitary gland. Explanation: The posterior pituitary hormones, ADH and oxytocin, are synthesized in the cell bodies of neurons in the hypothalamus that have axons that travel to the posterior pituitary, where they are released when needed. The two glands do not contribute components that are subsequently combined.
Imaging has proven useful in both the diagnosis and follow-up of endocrine disorders. Two types of imaging studies are useful when dealing with endocrine disorders: Isotopic imaging and non-isotopic imaging. What is an example of isotopic imaging? Renal angiography PET scan Thyroid scan MRI
Thyroid scan Explanation: Isotopic imaging includes radioactive scanning of the thyroid. The other answers are all examples of non-isotopic imaging.
In major athletic competition, athletes are required to submit to liquid chromatography testing looking for: - use of performance-enhancing agents to increase the chances of winning. - blood doping to increase RBC levels. - use of opioids to minimize pain during competition. - low serum sodium levels indicating dehydration.
use of performance-enhancing agents to increase the chances of winning. Explanation: For some steroid or peptide hormones, mass spectrometry is becoming increasingly useful and can be combined with other analytical techniques, such as liquid chromatography. These approaches provide definitive identification of the relevant hormone or compound according to its chemical or physical characteristics (e.g., unequivocal detection of performance-enhancing agents in sports).
The nurse is assessing a client with thyrotoxicosis and the nurse is explaining how the thyroid gland is stimulated to release thyroid hormones. The nurse should describe what process? Direct neural stimulation Steady-state continuous release Action of releasing hormones from hypothalamus Homeostatic receptors on surface of gland
Action of releasing hormones from hypothalamus Explanation: The synthesis and release of anterior pituitary hormones are largely regulated by the action of releasing or inhibiting hormones from the hypothalamus, which is the coordinating center of the brain for endocrine activity such as thyroid activity. There are no direct innervations for hormone release from the thyroid gland, and homeostatic receptors do not exist. Steady-state release of hormones does not occur.
Hormones can be synthesized by both vesicle-mediated pathways and non-vesicle-mediated pathways. What hormones are synthesized by non-vesicle-mediated pathways? Renin and angiotensin Androgens and estrogens Pepsin and ghrelin Neurotransmitters that are also hormones
Androgens and estrogens Explanation: Hormones that are synthesized by non-vesicle-mediated pathways include the glucocorticoids, androgens, estrogens, and mineralocorticoids—all steroids derived from cholesterol.
A client experiences an increase in thyroid hormone as a result of a thyroid tumor. Which hormonal response demonstrates the negative feedback mechanism? Decreased thyroid-stimulating hormone (TSH) Increased follicle-stimulating hormone (FSH) Increased thyrotropin-releasing hormone (TRH) Decreased adrenocorticotropic hormone (ACTH)
Decreased thyroid-stimulating hormone (TSH) Explanation: Negative feedback occurs when secretion of one hormone causes a reduction in the secretion of the hormone that stimulates production of the first hormone. In this case, TSH, which is manufactured by the anterior pituitary gland, would normally stimulate release of thyroid hormones, but with the increase of those hormones by the secreting tumor, enough thyroid hormones flood the system that there should be a reduction in TSH levels.
Which hormone is produced by the anterior pituitary gland? Norepinephrine Growth hormone (GH) Corticotropin-releasing hormone (CRH) Oxytocin
Growth hormone (GH) Explanation: GH is among the hormones produced and released by the anterior pituitary. Oxytocin is a posterior pituitary hormone, whereas CRH is produced by the hypothalamus. Norepinephrine and epinephrine are produced by the adrenal medulla.
When hypofunction of an endocrine organ is suspected, which type of diagnostic test can be administered to measure and assess target gland response? 24-hour urine Agglutination Hormone stimulation Antibody binding
Hormone stimulation Explanation: Stimulating hormone can be given to identify (determine hypofunction) if the target gland is able to increase hormone response to increased stimulation. Agglutination with enzymes is a way of measuring hormone antigen levels. The 24-hour urine sample measures hormone metabolite excretion. Radioactive hormone-antibody binding levels provide a method of measuring plasma levels.
Which gland acts as a signal-relaying bridge between multiple body systems and the pituitary gland? Posterior pituitary Hypothalamus Thyroid Parathyroid
Hypothalamus Explanation: The activity of the hypothalamus is regulated by both hormonally mediated signals (e.g., negative feedback signals) and by neuronal input from a number of sources. Neuronal signals are mediated by neurotransmitters such as acetylcholine, dopamine, norepinephrine, serotonin, gamma-aminobutyric acid (GABA), and opioids. Cytokines that are involved in immune and inflammatory responses, such as the interleukins, also are involved in the regulation of hypothalamic function. This is particularly true of the hormones involved in the hypothalamic-pituitary-adrenal axis. Thus, the hypothalamus can be viewed as a bridge by which signals from multiple systems are relayed to the pituitary gland. This cannot be said of the other options.
While teaching a science class, the instructor mentions that both autocrine and paracrine hormonal actions occur without entering the bloodstream. A student asks, "What cells do paracrine actions affect?" Which response is correct? Self Stored Local Target
Local Explanation: Paracrine actions are hormonal interactions with local cells other than those that produce the hormone; autocrine actions are with self-cells (cells from which they were produced). Both autocrine and paracrine hormonal actions affect target cells. Neither paracrine nor autocrine actions affect cell storage.
Which gland is often referred to as the master gland because it secretes many hormones? Hypothalamus Pancreas Pituitary Thyroid
Pituitary Explanation: The pituitary gland has been called the master gland because its hormones control the functions of many target glands and cells. That is not a term used to refer to the other options.
As part of maintaining homeostasis, why are hormones, secreted by endocrine cells, continuously inactivated? Absorb metabolic waste Free receptor sites Prevent accumulation Stimulate production
Prevent accumulation Explanation: Continuous inactivation of secreted hormones is necessary to prevent accumulation that could disrupt the feedback mechanism. Increased secretion stimulates production of more receptor sites. Metabolic waste absorption is not a function of the endocrine system.
Select the most accurate statement regarding measurements of urinary hormone. - Provide a better measure of hormone levels during a designated period. - Requires blood and urine sampling. - Discarded samples will not alter results. - Drugs will not alter testing results.
Provide a better measure of hormone levels during a designated period. Explanation: Measurements of urinary hormone or hormone metabolite excretion often are done on a 24-hour urine sample and provide a better measure of hormone levels during that period than hormones measured in an isolated blood sample. The advantages are relative ease of obtaining urine samples and blood sampling is not required. The disadvantages are that timed urine collections often are difficult to obtain and urine samples may be accidentally discarded or inaccurately preserved; drugs or disease states that alter hormone metabolism may interfere with the test results.
A client has received an injection containing thyrotropin-releasing hormone (TRH) and is now being assessed for serum levels of thyroid-stimulating hormone (TSH). Which type of diagnostic testing is this client undergoing? Suppression testing Autoantibody testing Radioimmunoassay (RIA) Stimulation testing
Stimulation testing Explanation: Introduction of TRH tests the pituitary gland's ability to produce TSH, and is an example of a stimulation test. Suppression testing examines a gland's response to a stimulus that would normally result in decreased hormone production. RIA and autoantibody testing are examples of direct and indirect measurement of serum levels of a hormone.
A client undergoing an evaluation of hormone levels asks, "What regulates the hormone levels?" Which response by the nurse would be considered most accurate? The positive feedback loop Exogenous forms of hormones The hypophysial portal system The hypothalamic-pituitary-target cell system
The hypothalamic-pituitary-target cell system Explanation: The levels of many of the hormones are regulated by feedback mechanisms that involve the hypothalamic-pituitary-target cell system. Positive feedback control refers to rising levels of a hormone that causes another gland to release a hormone that is stimulating to the first. The hypophyseal portal system connects the supraoptic and paraventricular nuclei of the hypothalamus with the posterior pituitary gland. Exogenous forms of hormones (given as drug preparations) can influence the normal feedback control of hormone production and release.
Which hormones exert paracrine action? Progesterone Epinephrine Estrogen Adrenocorticotropic hormone (ACTH) Insulin Calcitonin
Estrogen Progesterone Explanation: Hormones can exert four types of effects. Endocrine effects occur when the hormone is secreted into the blood and it travels to a distant site of action. Hormones that do this are epinephrine, calcitonin, and ACTH. Paracrine effects occur when the hormone acts locally on surrounding cells other than those that produced the hormone. Autocrine action is when the hormone produces a biologic effect on the cell that produced it. Insulin has that effect on pancreatic beta cells blocking further release. Intracrine action is when the hormone is produced and acts within the same cell.
Which hormone is secreted based on a cyclic rather than a diurnal manner? Antidiuretic hormone (ADH) Growth hormone Follicle-stimulating hormone (FSH) Adrenocorticotropic hormone (ACTH)
Follicle-stimulating hormone (FSH) Explanation: Hormone secretion varies widely over a 24-hour period. Some hormones, such as GH and adrenocorticotropic hormone (ACTH), have diurnal fluctuations that vary with the sleep-wake cycle. Others, such as the female sex hormones (e.g., follicle-stimulating hormone [FSH]) are secreted in a complicated cyclic manner. The levels of hormones such as insulin and antidiuretic hormone (ADH) are regulated by feedback mechanisms that monitor substances such as glucose (insulin) and water (ADH) in the body. The levels of many of the hormones are regulated by feedback mechanisms that involve the hypothalamic-pituitary-target cell system.
While discussing the regulation of hormone levels, the instructor gives an example of hormones regulated by feedback mechanisms. Which example of this regulation is best? - When a person's body pH is decreasing, the stomach lining becomes more acidic to offset this. - In children, the body knows to release growth hormones while they are sleeping instead of when they are awake and running around. - Following a meal that was high in carbohydrates, a person's blood glucose elevates, which stimulates the release of insulin from the pancreas. - When a female is thinking about getting pregnant, the body knows to release female sex hormones in greater proportion than usual.
Following a meal that was high in carbohydrates, a person's blood glucose elevates, which stimulates the release of insulin from the pancreas. Explanation: The levels of hormones such as insulin and antidiuretic hormone (ADH) are regulated by feedback mechanisms that monitor substances such as glucose (insulin) and water (ADH) in the body. None of the other examples are accurate examples of this feedback mechanism.
An adult client is scheduled for testing of a suspected growth hormone (GH)-secreting tumor. Which result from the glucose suppression test would confirm the condition? Increased GH secretion Decreased GH levels Hyperinsulinemia Hypoglycemia
Increased GH secretion Explanation: A suppression test is intended to determine if an organ that is oversecreting will respond to feedback to suppress that hormone. The glucose suppression test is used for an adult with acromegaly from excessive GH production. Normally, glucose would cause a decrease in GH secretion, but there is increased production of GH in response to the glucose in the test when the client has acromegaly.
Which organ system is matched with the preferred type of imaging? Ultrasound of bone density Magnetic resonance imaging (MRI) of the pituitary gland Dual energy x-ray absorptiometry (DXA) scan of the adrenal glands Computed tomography (CT) scan of the thyroid gland
Magnetic resonance imaging (MRI) of the pituitary gland Explanation: Preferred types of scans for endocrine tissues include MRI of the pituitary gland and hypothalamus, CT scan of the adrenal glands, DXA scan of bone density, and ultrasound of possible nodules of the thyroid gland.
A client with a history of brain tumors that resulted in partial removal of the pituitary gland years ago expresses concern to the health care provider about whether she will be able to breast-feed her infant. Which physiologic function of the pituitary gland facilitates breast milk production? Growth hormone (GH) Corticotropin-releasing hormone (CRH) Prolactin Oxytocin
Prolactin Explanation: The anterior pituitary gland or adenohypophysis contains five cell types: (1) thyrotrophs, which produce thyrotropin, also called TSH; (2) corticotrophs, which produce corticotropin, also called ACTH; (3) gonadotrophs, which produce the gonadotropins, LH and FSH; (4) somatotrophs, which produce GH; and (5) lactotrophs, which produce prolactin that is involved with breast growth and milk production.
Several hormones, including growth hormone (GH) and thyrotropin-releasing hormone (TRH), are bound to and carried by which substance? Prohormones Target cells Proteins Cholesterol
Proteins Explanation: Some hormones, such as steroids and thyroid hormone, are bound to protein carriers for transportation to the target cell destination. Cholesterol is a precursor for steroid hormone. Prohormones have an extra amino acid and convert to hormones in the Golgi complex.
When trying to explain hypothyroidism to a newly diagnosed client, the nurse stresses the fact that the thyroid hormone is transported in blood by specific: Prohormones Proteins Cholesterol molecules Target cells
Proteins Explanation: Some hormones, such as steroids and thyroid hormone, are bound to protein carriers for transportation to the target cell destination. The extent of carrier binding influences the rate at which hormones leave the blood and enter the cells. Cholesterol is a precursor for steroid hormone. Prohormones have an extra amino acid and are converted to hormones in the Golgi complex.
The physician suspects a client may be experiencing hypofunction of an endocrine organ. Select the most appropriate test to determine organ function. Imaging studies Genetic testing Stimulation tests Suppression tests
Stimulation tests Explanation: Stimulation tests are used when hypofunction of an endocrine organ is suspected. Suppression tests are used when hyperfunction of an endocrine organ is suspected. Genetic testing is used for DNA analysis, and imaging may be used as a follow-up after the diagnosis.
The nurse is teaching a client who has been newly diagnosed with hypothyroidism about the function of the thyroid. Which statement about the role of the thyroid gland is most accurate? - The thyroid gland releases neurotransmitters when the "flight or flight" mechanism is stimulated. - The thyroid gland promotes development of secondary sex characteristics. - The thyroid gland is responsible for regulating serum calcium levels. - The thyroid gland is responsible for increasing the metabolic rate.
The thyroid gland is responsible for increasing the metabolic rate. Explanation: The thyroid gland produces thyroid hormones, T3 and T4. These hormones increase the metabolic rate; increase protein and bone turnover; increase responsiveness to catecholamines; are necessary for fetal and infant growth and development. The parathyroid gland regulates calcium metabolism. The adrenal glands regulate "flight or fight" and the testes or ovaries regulate development of secondary sex characteristics.
A client with hyperthyroidism is being treated with medication that blocks the activity of thyroid-stimulating hormone. Her care team has determined that she has been overproducing TSH. This client will have lost her ability to: metabolize TSH. have negative feedback regulation. metabolize thyroxin. have positive feedback regulation.
have negative feedback regulation. Explanation: When the sensors detect a decrease in hormone levels, they initiate changes that cause an increase in hormone production; when hormone levels rise above the set point of the system, the sensors cause hormone production and release to decrease. Positive feedback increases activity rather than shuts if off. Metabolism of the hormone is not an issue in regulation.
Which type of imaging is preferred to evaluate the bone density of a client with hyperparathyroidism? Ultrasound Dual energy x-ray absorptiometry (DXA) scan Computed tomography (CT) scan Magnetic resonance imaging (MRI)
Dual energy x-ray absorptiometry (DXA) scan Explanation: Preferred types of scans for endocrine tissues include MRI of the pituitary gland and hypothalamus, CT scan of the adrenal glands, DXA scan of bone density, and ultrasound of possible nodules of the thyroid gland. Bone density may be decreased in a client with hyperparathyroidism.
