Introduction to the Endocrine System

1.

The nurse is discussing the endocrine system with a class of nursing students. What substance would the nurse label as a hormone?
A)
Acetylcholine
B)
Norepinephrine
C)
Nucleic acid
D)
Serotonin
Ans:
B

Feedback:

A hormone is secreted directly into the bloodstream and travels from the site of production to react with specific receptor sites to cause an action. Norepinephrine, which is a neurotransmitter, is a hormone when it is produced in the adrenal medulla, secreted into circulation, and travels to norepinephrine receptor sites to cause an effect. Acetylcholine and serotonin are neurotransmitters, but are not hormones. Nucleic acid is used to build deoxyribonucleic acid and ribonucleic acid.

2.

What organ should the nurse recognize as the coordinating center for the nervous and endocrine responses to internal and external stimuli?
A)
Hypothalamus
B)
Pituitary gland
C)
Thyroid gland
D)
Parathyroid gland
Ans:
A

Feedback:

The hypothalamus is the coordinating center for the nervous and endocrine responses to internal and external stimuli. The pituitary, thyroid, and parathyroid glands all play an important role in maintaining homeostasis, but they do not connect the nervous and endocrine systems.

3.

What criteria can the nurse use to describe all hormones?
A)
They are produced in very large amounts.
B)
They circulate until they are used by receptor cells.
C)
They are secreted directly into the tissue where they react.
D)
They travel in the blood to specific receptor sites.
Ans:
D

Feedback:

Hormones are chemicals that are produced in the body and meet specific criteria. All hormones are produced in very small amounts and are secreted directly into the bloodstream. They travel in the blood to specific receptor sites throughout the body and are immediately broken down.

4.

The nurse is caring for a patient with abnormal calcium levels. What thyroid hormone does the nurse expect this will impact?
A)
Aldosterone
B)
Calcitonin
C)
Erythropoietin
D)
Insulin
Ans:
B

Feedback:

Calcitonin is produced and secreted by the thyroid gland in direct response to serum calcium levels. Aldosterone is an adrenocorticoid hormone that is released in response to adrenocorticotropic hormone. Erythropoietin is released by the juxtaglomerular cells in the kidney in response to decreased pressure or decreased oxygenation of the blood flowing into the glomerulus. Insulin is produced by the pancreas in response to varying blood glucose levels.

5.

The nurse explains the end result of the hypothalamus in regulating the central nervous system (CNS), autonomic nervous system (ANS), and endocrine system is what?
A)
Regulation of the negative feedback system
B)
Creation of a diurnal rhythm
C)
Maintenance of homeostasis
D)
Production of prolactin-inhibiting factor (PIF)
Ans:
C

Feedback:

The hypothalamus maintains internal homeostasis by sensing blood chemistries and by stimulating or suppressing endocrine, autonomic, and CNS activity. In essence, it can turn the ANS and its effects on or off. The negative feedback system is one way homeostasis is maintained. When the hypothalamus senses a need for a particular hormone, it secretes a releasing factor directly into an area such as the anterior pituitary. This causes the area to produce a hormone. When the hypothalamus senses a rising level of the hormone it stops secreting the releasing factor, which decreases the hormone production. When this occurs the hypothalamus senses the falling hormone level and the releasing factor is secreted again. This process is how the hormone level is maintained. Diurnal rhythm refers to the release of hormones at various times of the day. PIF, produced by the hypothalamus, acts as a regulator to shut off production of hormones when levels become too high.

6.

While caring for a diabetic patient, the nurse explains that normally insulin is produced by the pancreas and does what when reacting with the human cell?
A)
Metabolizes glucose
B)
Allows water to enter the cell
C)
Alters cellular messenger ribonucleic acid (RNA)
D)
Changes the cell permeability to glucose
Ans:
D

Feedback:

Insulin reacts with specific receptor sites on the cell membrane to change the cell’s permeability to glucose to allow glucose to enter the cell. It does not affect water transport or messenger RNA. Insulin does not metabolize glucose but rather helps it move into the cell where it supplies energy for cellular activity.

7.

What hormone enters the cell and reacts with a receptor inside the cell to change messenger ribonucleic acid and affect the cell’s function?
A)
Estrogen
B)
Insulin
C)
Calcitonin
D)
Thyroid-stimulating hormone
Ans:
A

Feedback:

Estrogen enters the cell and reacts with a receptor site inside of the cell to make changes and produce an action. This does not happen quickly, and it may take months to years to produce the changes. Estrogen, calcitonin, and thyroid-stimulating hormone react with specific receptor sites on the cell membrane to stimulate change and action within the cell.

8.

The patient’s body modulates pain perception as a result of the production of what in the intermediate lobe of the pituitary gland?
A)
Antidiuretic hormone (ADH)
B)
Endorphins
C)
Adrenocorticotropic hormone (ACTH)
D)
Oxytocin
Ans:
B

Feedback:

Endorphins and enkephalins are produced by the intermediate lobe of the pituitary gland. Oxytocin and ADH are produced by the posterior pituitary gland, and ACTH is produced by the anterior pituitary gland.

9.

The nurse explains the purpose of the negative feedback system used by the endocrine system is what?
A)
To change the environment of the pituitary gland
B)
To regulate hormone release
C)
To maintain hormone concentration at a certain level
D)
To control the action of hormones
Ans:
C

Feedback:

The negative feedback system is a control system in which increasing levels of a hormone lead to decreased levels of releasing and stimulating hormones, leading to decreased hormone levels, which stimulates the release of releasing and stimulating hormones; it allows tight control of the endocrine system. It does not involve changing the environment or control the action of hormones.

10.

Melanocyte-stimulating hormone (MSH) released from the anterior pituitary is important in humans because of its suspected ability to do what?
A)
Block the perception of pain
B)
Change the color of skin in some environments
C)
Stimulate fat mobilization
D)
Stimulate nerve growth and development
Ans:
D

Feedback:

MSH might be important for nerve growth and development in humans. Animals use MSH to change skin color as part of protective camouflage, but it does not have this effect in humans. Lipotropins stimulate fat mobilization. Endorphins and enkephalins are hormones that block the perception of pain.

11.

The nurse is caring for a patient diagnosed with a condition resulting in inadequate production of cholecystokinin. What would the nurse expect to find when assessing this patient?
A)
Elevated serum sodium and reduced serum potassium levels
B)
Decreased bowel sounds
C)
Increased numbers of red blood cells
D)
Increased serum calcium levels
Ans:
B

Feedback:

Cholecystokinin is secreted by the intestine and decreases gastric movement resulting in diminished bowel sounds as well as stimulation of bile and pancreatic juice secretion. Aldosterone causes sodium retention and potassium excretion. Erythropoietin increases red blood cell production. Parathyroid hormone causes an increase in serum calcium levels.

12.

A group of nursing students are developing a presentation on hormones. What hormone will the students’ presentation identify as regulating the metabolic rate and influencing the growth and development of the body?
A)
Parathyroid hormone or parathormone
B)
Thyroid hormone
C)
Cortisol
D)
Insulin
Ans:
B

Feedback:

Thyroid hormone regulates the metabolic rate of the body and greatly influence growth and development. Parathormone, cortisol, and insulin do not regulate the metabolic rate or influence growth and development.

13.

The patient’s anterior pituitary hormone secretion is impacted by time of day and activity level, which the nurse assesses as what?
A)
Diurnal rhythm
B)
Physiological rhythm
C)
Circadian rhythm
D)
Biannual rhythm
Ans:
A

Feedback:

The anterior pituitary hormones are released in a rhythmic manner into the bloodstream. Their secretion varies with time of day (often referred to as diurnal rhythm) or with physiological conditions, such as exercise or sleep. A biannual rhythm would be twice a year. Circadian rhythm is indicated by when the patient prefers to sleep or wake, such as those who describe themselves as “morning people.” There is no such thing as a physiological rhythm.

14.

Some hormones react with specific receptor sites on a cell membrane and stimulate what?
A)
Meiosis
B)
Cyclic adenosine monophosphate (cAMP)
C)
Increase in hormonal inactivity
D)
Decrease in hormonal activity
Ans:
B

Feedback:

Some hormones react with specific receptor sites on a cell membrane to stimulate the nucleotide cAMP within the cell to elicit an effect. Hormones that react with specific receptor sites do not stimulate miosis, or a change in amount of hormonal activity, either an increase or decrease, which would be regulated by a negative feedback mechanism.

15.

Estrogen enters the cell and reacts with a receptor site. What is the final result of this reaction?
A)
Deoxyribonucleic acid (DNA) is affected.
B)
Ribonucleic acid enters the cell nucleus.
C)
Alteration in cellular function
D)
Changes messenger RNA
Ans:
C

Feedback:

Estrogen enters the cell and reacts with a receptor site inside the cell to change messenger RNA, which enters the cell nucleus to affect cellular DNA, and the final result is an alteration in the cell’s function.

16.

The nurse is preparing a class on the endocrine system for students. What benefit is served by the positioning of the hypothalamus in the brain? (Select all that apply.)
A)
Close to other important areas of the brain
B)
Able to influence and be influenced by emotions and thoughts
C)
Poorly protected by the blood–brain barrier
D)
Floats within ventricles of the brain
E)
Protected from the limbic system
Ans:
A, B, C

Feedback:

Situated at the base of the forebrain, the hypothalamus receives input from virtually all other areas of the brain, including the limbic system, cerebral cortex and the special senses that are controlled by the cranial nerves: smell, sight, touch, taste, hearing. Because of its positioning, the hypothalamus is able to influence, and be influenced by, emotions and thoughts. The hypothalamus also is located in an area of the brain that is poorly protected by the blood–brain barrier, so it is able to act as a sensor to various electrolytes, chemicals, and hormones that are in circulation and do not affect other areas of the brain. It does not float within the ventricles of the brain, and it is located to allow input from the limbic system.

17.

The nurse is caring for a pregnant patient. What hormone must be secreted to cause uterine contractions?
A)
Oxytocin
B)
ADHD
C)
Estrogen
D)
Enkephalins
Ans:
A

Feedback:

The pituitary is made up of three lobes: anterior, intermediate, and posterior. The posterior lobe stores two hormones produced by the hypothalamus, ADH and oxytocin. Oxytocin stimulates uterine smooth muscle contraction in late phases of pregnancy and also causes milk release or “let down” reflex in lactating women. The posterior lobe does not store estrogen or enkephalins. ADHD (i.e., attention deficit hyperactivity disorder is a disease process, not a hormone.

18.

What receptors in the body stimulate the hypothalamus to release antidiuretic hormone (ADH)?
A)
Diuretic receptors
B)
Osmoreceptors
C)
Alpha receptors
D)
Nicotinic receptors
Ans:
B

Feedback:

The osmoreceptors in the hypothalamus stimulate the release of ADH. There is no such thing as a diuretic receptor. Alpha receptors are associated with the sympathetic nervous system and nicotinic receptors are associated with the parasympathetic nervous system.

19.

What are the areas of the hypothalamus called that are specifically sensitive to certain stimuli to regulate body functions?
A)
Nodes
B)
Lobes
C)
Neurocenters
D)
Epicenters
Ans:
C

Feedback:

The hypothalamus has various neurocenters—areas specifically sensitive to certain stimuli—that regulate various body functions, including body temperature, thirst, hunger, water retention, blood pressure, respiration, reproduction, and emotional reactions. Areas of special sensitivity in the hypothalamus are not called depots, lobes, or epicenters.

20.

The hypothalamus receives input from virtually all other areas of the brain. Where is the hypothalamus located?
A)
Behind the frontal lobe
B)
In the substantia nigra
C)
At the base of the pons
D)
At the base of the forebrain
Ans:
D

Feedback:

Situated at the base of the forebrain, the hypothalamus receives input from virtually all other areas of the brain, including the limbic system and the cerebral cortex. Therefore, the other options are incorrect.

21.

The hypothalamus fine-tunes and regulates the release of hormones using what process?
A)
Negative feedback systems
B)
Indirect feedback systems
C)
Direct local input
D)
Direct release of hormones into bloodstream
Ans:
A

Feedback:

The fine-tuning and regulation of hormone release through the hypothalamus is often regulated by a series of negative feedback systems. Other options are incorrect answers as they are distracters for this question.

22.

To better understand the negative feedback system, what might the nurse compare it with?
A)
The actions of use and disuse
B)
The law of supply and demand
C)
The concept of need and use
D)
The contract of give and take
Ans:
B

Feedback:

A negative feedback system works much like the law of supply and demand in business. In business, when the supply of a product is adequate, production of that product will be cut back because demand is not there. Other options are distracters for this question.

23.

When the hypothalamus senses a need for thyroid hormone, where does it secrete the releasing factor thyrotropin-releasing hormone (TRH)?
A)
Directly into the posterior pituitary
B)
Directly into the bloodstream
C)
Directly into the anterior pituitary
D)
Directly into the thyroid gland
Ans:
C

Feedback:

When the hypothalamus senses a need for a particular hormone, it secretes TRH directly into the anterior pituitary. Other options, therefore, are incorrect.

24.

What hormones does the pancreas produce and release that aids in the body’s varying blood glucose levels? (Select all that apply.)
A)
Insulin
B)
Antidiuretic hormone (ADH)
C)
Glucagon
D)
Somatostatin
E)
Amylase
Ans:
A, C, D

Feedback:

Hormones other than stimulating hormones are also released in response to stimuli. For example, the endocrine pancreas produces and releases insulin, glucagon, and somatostatin from different cells in response to varying blood glucose levels. ADH does not respond to blood glucose levels but controls sodium and potassium levels. Amylase is an enzyme released by the pancreas.

25.

The hypothalamic–pituitary axis (HPA) functions through one of two processes to regulate hormone production. One of these processes is the negative feedback system. What is the other process?
A)
Direct use of inhibiting factors
B)
Indirect use of feedback loop
C)
Direct use of releasing factors
D)
Indirect use of stimulating factors
Ans:
A

Feedback:

The HPA functions through negative feedback loops or the direct use of inhibiting factors to constantly keep particular hormones regulated. Other options are incorrect because hormones are not regulated by feedback loops, releasing factors, or stimulating factors.

26.

The nurse administers an exogenous hormone to the patient. How does the nurse’s action impact the endocrine system? (Select all that apply.)
A)
May decrease exogenous hormone levels
B)
May increase hormone levels in the body
C)
May stop production of releasing and stimulating hormones
D)
May lead to a decrease in the normal production of the hormone
E)
May increase the endogenous hormone levels
Ans:
B, C, D

Feedback:

Supplying an exogenous hormone may increase the hormone levels in the body, but then might affect the hypothalamic–pituitary axis (HPA) to stop production of releasing and stimulating hormones, leading to a decrease in the body’s normal production of the hormone. Supplying exogenous hormone will not cause a decrease in exogenous hormone levels nor will it cause an increase in endogenous hormone levels.

27.

The nursing instructor is talking with her clinical group about the hypothalamic–pituitary axis (HPA) and what happens when a need arises to interact with the total system. The instructor explains that this can create what?
A)
A negative feedback system
B)
Homeostasis
C)
Complications
D)
Maximum efficiency
Ans:
C

Feedback:

This system (i.e., the HPA) also can create complications, especially when a need exists to override or interact with the total system, as is the case with replacement therapy or treatment of endocrine disorders. Interactions with the total system cannot create a negative feedback system, homeostasis, or maximum efficiency. The other options are incorrect.

28.

What is the connecting link between the nervous system and the endocrine system?
A)
Hypothalamus
B)
Thalamus
C)
Medulla oblongata
D)
Posterior pituitary
Ans:
A

Feedback:

The main connecting link between the nervous system and the endocrine system is the hypothalamus, which responds to nervous system stimulation by producing hormones. The thalamus and medulla oblongata are part of the nervous system and the posterior pituitary is part of the endocrine system but none of these represents a link between the two systems.

29.

When the student develops a poster of the endocrine system, what gland will be excluded because it is not classified as a major organ of the endocrine system?
A)
Hypothalamus
B)
Pituitary
C)
Thyroid
D)
Gallbladder
Ans:
D

Feedback:

The gallbladder is not part of the endocrine system and does not secrete hormones. All other options are organs of the endocrine system.

30.

What is a releasing hormone?
A)
Chemical that interacts with a hormone to activate it
B)
Chemical released by the body to stimulate the hypothalamus
C)
Chemical released by the body organs to stimulate the pituitary
D)
Chemical released by the hypothalamus into the anterior pituitary
Ans:
B

Feedback:

Releasing hormones or factors are chemicals released by the hypothalamus into the anterior pituitary to stimulate the release of anterior pituitary hormones. The releasing hormone does not activate a hormone but stimulates its production. It does not stimulate the glands (hypothalamus or pituitary) but rather stimulates release of an anterior pituitary hormone.

31.

The nurse overhears a physician talking about the “master gland.” What gland does the nurse recognize is being discussed?
A)
The pituitary gland
B)
The hypothalamus gland
C)
The thyroid gland
D)
The parathyroid gland
Ans:
B

Feedback:

Scientists now designate the hypothalamus as the master gland because it has even greater direct regulatory effects over the neuroendocrine system, including stimulation of the pituitary gland to produce its hormones. The pituitary gland was formerly considered the master gland, but new research has helped scientists realize it is the hypothalamus that is the master gland.

32.

The nurse administers a thyroid hormone replacement pill to the patient. What effect will this action have on the patient’s production of thyroid hormones?
A)
Stimulates the gland that normally produces that hormone
B)
Stops production of releasing and stimulating hormones
C)
Initiates the negative feedback system
D)
Stimulates the hypothalamic–pituitary axis
Ans:
B

Feedback:

Supplying an exogenous hormone may increase the hormone levels in the body, but it then may affect the hypothalamic–pituitary axis (HPA) to stop production of releasing and stimulating hormones, leading to a decrease in the body’s normal production of the hormone. It does not stimulate the gland or the HPA. It also does not trigger a negative feedback response.

33.

What hormones do not have a target organ to produce hormones and cannot be regulated by the same feedback as other hormones?
A)
Growth hormone and prolactin
B)
Estrogen and progesterone
C)
Erythropoietin and renin
D)
Insulin and glucagon
Ans:
A

Feedback:

Two of the anterior pituitary hormones (i.e., growth hormone and prolactin) do not have a target organ to produce hormones and so cannot be regulated by the same type of feedback mechanism. Estrogen and progesterone have the uterus, ovaries, and breast, as their target organs. The target organs for erythropoietin is the bone marrow, for renin it is the arteries, and insulin and glucagon come from the pancreas to stimulate cells to metabolize glucose and regulate serum glucose levels

34.

What qualifies the hypothalamus to be called the master gland?
A)
It regulates the nervous and endocrine responses to stimuli.
B)
It stimulates the pituitary gland to control the endocrine system.
C)
It combines the nervous and endocrine system to work together.
D)
It produces all of the releasing hormones in the body.
Ans:
B

Feedback:

The hypothalamus gland is called the master gland of the neuroendocrine system because it regulates both nervous and endocrine responses to internal and external stimuli. There is more to the hypothalamus than just its stimulation of the pituitary gland or its production of releasing hormones that leads it to be considered the master gland. The neuroendocrine system combines the nervous and endocrine systems to work closely together to maintain regulatory control and homeostasis in the body.