Question 1

Which of the following statements best captures an aspect of the role of hormones in the body?

Accepted Answer

Some chemicals, such as epinephrine, can both function as a hormone and be closely integrated with the central and peripheral nervous systems as well as the immune systems, leading to current terminology such as "neuroendocrine." Hormones modulate, but do not initiate, changes in the body, and one hormone may exert multiple effects on multiple body systems. Hormones are produced by a variety of body tissues, not solely by endocrine glands.

Question 2

An example of a single hormone that can exert effects in different tissues, erythropoietin, made in the kidney stimulates the bone marrow to produce

Accepted Answer

A characteristic of hormones is that a single hormone can exert various effects in different tissues. For example, erythropoietin, a traditional circulating hormone, is made in the kidney and stimulates erythropoiesis in the bone marrow.

Question 3

A nurse who works in the office of an endocrinologist is orienting a new staff member. Which of the following teaching points is the nurse justified in including in the orientation? Select all that apply.

Accepted Answer

A single hormone can exert various effects in different tissues or, conversely, a single function can be regulated by several different hormones. Hormones act both distant from their source and more locally, as in the case of autocrine and paracrine actions. Hormones are normally present at all times.

Question 4

When explaining about structural classifications to a group of students, the instructor discusses the peptides and proteins. They talk about small hormones and hormones as large and complex as growth hormone (GH), which has approximately how many amino acids involved?

Accepted Answer

Growth hormone is a very large and complex protein that has approximately 200 amino acids.

Question 5

Which of the following hormones are derivatives of cholesterol?

Accepted Answer

Steroids such as aldosterone and testosterone are a classification of hormones that are derived from cholesterol. Epinephrine and norepinephrine are both amino acids, while insulin and glucagon are classified among peptides, polypeptides, proteins, and glycoproteins. Eicosanoids and retinoids consist of fatty acid compounds.

Question 6

A 51-year-old woman has been experiencing signs and symptoms of perimenopause and has sought help from her family physician. A deficiency in estrogen levels has been determined to be a contributing factor. Which of the following phenomena could potentially underlie the woman's health problem?

Accepted Answer

Steroids such as estrogen are produced in the smooth endoplasmic reticulum. Synthesis and release are not separate processes as in the case of peptide hormones, and prohormones are associated with peptide, polypeptide, and protein hormones.

Question 7

Which of the following best describes the half-life of a highly protein-bound drug such as thyroxine (99% protein bound)? The half-life would be

Accepted Answer

The half-life of a hormone-the time it takes for the body to reduce the concentration of the hormone by one half-is positively correlated with its percentage of protein binding. Thyroxine, which is more than 99% protein bound, has a half-life of 6 days, whereas aldosterone, 15% bound, has a half-life of only 25 minutes.

Question 8

Since steroid hormones are bound to protein carriers for transport, this means

Accepted Answer

Steroid hormones are bound to protein carriers for transport and are inactive in the bound state. Their activity depends on the availability of transport carriers.

Question 9

Neurotransmitters like catecholamines (e.g., dopamine and epinephrine) have a reaction time of

Accepted Answer

The neurotransmitters, which control the opening of ion channels, have a reaction time of milliseconds.

Question 10

A client with a history of an endocrine disorder exhibits signs and symptoms of hormone deficiency. Which of the following processes would the client's care team most likely rule out first as a contributing factor?

Accepted Answer

Up-regulation is a response to low hormone levels in which the number of receptors increases. As such, it would not likely result in signs and symptoms of deficiency but is rather a compensatory mechanism that counters a deficiency. Insufficient numbers of receptors, low affinity, and down-regulation could all contribute to signs and symptoms of a hormone deficiency.

Question 11

Which of the following statements best captures the essence of a second messenger in the mechanisms of the endocrine system?

Accepted Answer

Second messengers interact with hormones that cannot cross the cell membrane, and they mediate the ultimate effect on the cell. They are not produced by thehormone-producing cell, and they are necessary to bring about hormonal effects, not simply for increasing the intensity of the effect. They are not an alternative mechanism of effect but rather a prerequisite for certain hormonal effects on body cells.

Question 12

A client with a new diagnosis of an endocrine disorder is unclear how the body can control the levels of different hormones over time. Which of the following statements most accurately underlies the dominant regulation process of hormone levels in the body?

Accepted Answer

Most hormone levels are controlled by way of a negative feedback cycle, in which low levels stimulate production and/or release. A positive feedback cycle would not achieve this effect. While some hormones are released on a diurnal schedule, the dominant form of hormone regulation in the body is that of negative feedback. Hormone release is not predetermined by the pituitary gland.

Question 13

A 21-year-old female is suspected of having inadequate function of her hypothalamic- pituitary-thyroid system. Her care provider is planning to inject thyrotropin-releasing hormone (TRH) and then measure her levels of TSH. Which of thefollowing diagnostic tests is being performed?

Accepted Answer

A stimulation test involves the introduction of an element that stimulates the production of another factor or hormone followed by measurement of that hormone. This is not the case in a suppression test, RIA test, or metabolite excretion test.

Question 14

Following a meal, a woman's blood glucose level has increased. In addition, her pancreas has increased the amount of insulin produced and released. Which of the following phenomena has occurred?

Accepted Answer

The level of some hormones is adjusted according to the amount of the substance that they control. In this case, insulin controls glucose levels and would increase in response to the increase in serum glucose that follows a meal. This differs from a negative feedback cycle in which a simple decrease in a hormone level stimulates production and/or release of that hormone. Positive feedback and hypothalamic-pituitary control are not evident in this situation.

Question 15

Which of the following statements best captures the relationship between the hypothalamus and the pituitary gland as it relates to endocrine function?

Accepted Answer

The hypothalamus can be viewed as a bridge by which signals from multiple systems are relayed to the pituitary gland. The hypothalamus collects data from sources throughout the body rather than directly measuring levels, and communication normally flows from the hypothalamus to the pituitary.

Question 16

A 38-year-old woman takes clomiphene, an infertility drug that works by competing with, and thereby blocking, cellular receptors for estrogen. Which of the following statements is most likely to be true of this client?

Accepted Answer

Because estrogen is a steroid hormone, its receptors in target cells are located inside the cell membrane, and their blockage does not affect the movement of the hormone into and out of the cell. Receptors are specific for each hormone, so no hormones other than estrogen will be blocked. Up-regulation occurs when hormone levels are decreased, and in this case, the estrogen level will increase. Second messengers, such as cAMP, are only activated by peptide hormones and catecholamines.

Question 17

During the follicular stage of menstruation, increased estradiol production causes an increase in FSH production. This increase in FSH production by the anterior pituitary gland will have what effect on the follicle?

Accepted Answer

In positive feedback control, rising levels of a hormone cause another gland to release a hormone that is stimulating to the first. Increased estradiol production during the follicular stage of the menstrual cycle causes increased FSH production by the anterior pituitary gland. This stimulates further increases in estradiol levels until the demise of the follicle.

Question 18

A middle-aged woman has acromegaly as a result of a pituitary adenoma that was found and removed when she was a teenager. The physician is suspecting that the tumor has returned and has ordered a diagnostic work-up. A glucose load is ordered. If the tumor has returned, the nurse would expect which of the following results?

Accepted Answer

When a GH-secreting tumor is suspected, the GH response to a glucose load is measured as part of the diagnostic workup. Normally, a glucose load would suppress GH levels. However, in adults with GH-secreting tumors (acromegaly), GH levels are not suppressed (and paradoxically increase in 50% of cases) to a glucose load.

Question 19

A patient exhibiting problems with his or her thyroid has been scheduled for a radioactive scan. From the following list of patients, what would the nurse question as to whether this would be a safe procedure for this patient?

Accepted Answer

Radioactive iodine therapy is contraindicated in pregnant women because ¹³¹I crosses the placenta and can adversely affect the fetal thyroid gland. The other clients would have no contraindication to the substance.

Question 20

A 48-year-old woman has been found to have nodules on her thyroid that must be biopsied to determine whether or not they are malignant. Which of the following imaging techniques will be most helpful to the surgeon in visualization of the nodes for fine needle aspiration?

Accepted Answer

Thyroid ultrasound is recommended for managing thyroid nodules and can aid in visualization of the nodule for biopsy (fine needle aspiration [FNA]), which is necessary to help distinguish benign from malignant etiology. Magnetic resonance imaging is the preferred choice for pituitary and hypothalamic imaging. Isotopic imaging includes radioactive scanning of the thyroid (e.g., using radioiodine), parathyroids (e.g., using sestamibi), and adrenals (e.g., using metaiodobenzylguanidine [MIBG] to detect pheochromocytoma).

Quiz 46: Sexually Transmitted Infections