Deck 18: Principles of Endocrinology: the Central Endocrine Glands

Question 1

Which class(es) of hormones is/are released by exocytosis upon appropriate stimulation?

A)peptides
B)catecholamines
C)steroids
D)thyroid hormone
E)Both a and b

Answer 1

E

Question 2

Which statement about tropic hormones is incorrect?

A)They may stimulate the secretion of other hormones.
B)They target other glands.
C)They are all produced in the anterior pituitary gland.
D)Both a and b
E)All of the above

Answer 2

C

Question 3

____________ is/are synthesized by the endoplasmic reticulum-Golgi complex mechanism.

A)Peptides
B)Catecholamines
C)Steroids
D)Thyroid hormone
E)Both b and d

Answer 3

A

Question 4

Which statement is incorrect?

A)A single endocrine gland may produce multiple hormones.
B)A single target cell may be influenced by more than one hormone.
C)A single hormone can influence only one type of target cell.
D)An endocrine organ may secrete non-endocrine substances in addition to hormones.
E)The same hormone may be secreted by more than one endocrine gland.

Question 5

Tropic hormones

A)are produced by the posterior pituitary
B)are secreted only by the hypothalamus
C)primarily regulate hormone secretion by certain other endocrine glands
D)all have non-tropic functions too
E)are the hormones that stimulate athletes to win trophies

Question 6

Hormones

A)are all of similar chemical composition
B)combine with specific receptors on the target cell's surface or inside the target cell
C)are secreted at a constant rate
D)all act by activating adenylate cyclase, which transforms ATP into cyclic AMP
E)have all of the above characteristics

Question 7

Which statement regarding endocrine glands is incorrect?

A)They produce hormones.
B)They secrete their products into the blood.
C)They are comprised of epithelial tissue.
D)They are all controlled by the nervous system.
E)They are ductless.

Question 8

The specificity of hormones is due to

A)specialized hormone secretion
B)molecular rearrangement at the site of action
C)specific binding of hormones to plasma proteins
D)specialization of target-cell receptors
E)inactivation of hormones by the kidneys

Question 9

Hormones are classified into three types:

A)amines, peptides, and steroids
B)amines, steroids, and phospholipids
C)amines, phospholipids, and steroids
D)amines, free fatty acids, and peptides
E)free fatty acids, peptides, and steroids

Question 10

The transport of lipid-soluble hormones in the blood is accomplished by

A)loose binding with albumin
B)specific binding to plasma proteins
C)binding with tropic hormones
D)both a and b
E)none of the above

Question 11

___________ is/are not stored in the secretory cell after being synthesized.

A)Peptides
B)Catecholamines
C)Steroids
D)Thyroid hormone
E)b and c

Question 12

Neurosecretory neurons

A)release neurotransmitters
B)release hormones
C)are unable to conduct action potentials, unlike ordinary neurons
D)perform both a and b
E)are found in most endocrine glands

Question 13

All hormones

A)are regulated by the hypothalamus
B)initiate synthesis of new proteins
C)are secreted by endocrine glands through ducts into the blood
D)must combine with specific receptors on the target cells in order to exert their effects
E)are eventually inactivated by enzymes in the liver, kidneys, blood, or target cells

Question 14

____________ is not controlled, at least in part, by hormones.

A)Homeostasis
B)Organic metabolism
C)Rapid interactions with the external environment
D)H2O and electrolyte balance
E)Adaptation to stress

Question 15

Which of the following is true about hormones?

A)They are released from exocrine glands.
B)They interact with receptors at target-cell sites.
C)They are synthesized in the lymph nodes.
D)They interact with receptors in the blood.
E)They are all similar chemically.

Question 16

Which class of hormones are polar and, accordingly, hydrophilic?

A)Peptides
B)Catecholamines
C)Steroids
D)Both a and b
E)None of the above

Question 17

_________ is not a tropic hormone.

A)ACTH
B)ADH
C)GIP
D)LH
E)TSH

Question 18

Which of the following is not a function of the endocrine system?

A)Maintenance of blood sugar levels
B)Regulation of metabolic activity and H2O and electrolyte balance
C)Promotion of growth and development
D)Transduction of external stimuli
E)Helping the body cope with stressful situations

Question 19

Select the incorrect statement about peptide hormones.

A)They include adrenal cortex hormones.
B)Insulin is an example.
C)They are stored within secretory granules.
D)They are secreted from endocrine glands.
E)They must bind to membrane receptors to invoke their actions.

Question 20

Amines are

A)chains of specific amino acids of varying length
B)derived from the amino acid tyrosine
C)hormones secreted by the thyroid gland and adrenal medulla
D)all of the above
E)only a and c

Question 21

Diurnal rhythms are

A)are inherent cyclical peaks and ebbs of hormone secretion that are a function of time and are entrained to the 24-hour light-dark cycle
B)are important in maintaining hormone levels at a relatively constant set point no matter the time of day
C)mainly associated with adrenal hormones
D)are all of the above
E)none of the above

Question 22

Which statement is not correct?

A)Normally the effective plasma concentration of a hormone is regulated by appropriate adjustments in the rate of its secretion.
B)In order to maintain homeostasis, the rate of hormone secretion remains constant.
C)All hormones are regulated through negative feedback controls.
D)Neuroendocrine reflexes produce a sudden increase in hormone secretion in response to a specific, usually external, stimulus.
E)Some organs have endocrine and exocrine functions.

Question 23

In the process of negative feedback,

A)TSH inhibits thyroid hormone secretion by the thyroid gland
B)thyroid hormone inhibits TSH secretion by the anterior pituitary
C)thyroid hormone directly inhibits further thyroid hormone secretion by the thyroid gland
D)TRH inhibits TSH secretion by the anterior pituitary
E)thyroid hormone and TRH inhibit TSH secretion by the anterior pituitary

Question 24

Peptide hormones

A)are synthesized from modified cholesterol molecules
B)are typically not bound to plasma proteins in the blood
C)bind to intracellular receptors at their target cells
D)typically activate genes to cause the synthesis of new protein molecules
E)have characteristics c and d

Question 25

Lipophilic hormones must interact with __________ prior to gene activation.

A)membrane receptors
B)G-proteins
C)intracellular receptors
D)adenylate cyclase
E)both b and d

Question 26

The most common second messenger used by hydrophilic hormones is

A)calcium
B)cyclic AMP
C)chromatin
D)messenger RNA
E)plasma proteins

Question 27

Steroid hormones are

A)lipophilic
B)derived from cholesterol
C)able to initiate the synthesis of specific new proteins within their target cells
D)both a and b
E)all of the above

Question 28

Estrogens, testosterone, cortisol, and aldosterone are all derived from

A)tyrosine
B)cholesterol
C)phospholipid
D)IGF-2
E)epinephrine

Question 29

Which of the following is least associated with the hydrophilic hormones?

A)cyclic AMP
B)protein kinase
C)adenylate cyclase
D)intracellular receptor
E)phosphorylated enzymes

Question 30

Select the correct statement about TSH.

A)A buildup of the thyroid hormone stimulates its production by negative feedback.
B)It is secreted by the thyroid gland.
C)It is stored in the posterior pituitary.
D)It stimulates the thyroid gland.
E)Its activity is unrelated to a set point.

Question 31

___________ do(es) not require membrane receptors to invoke cell responses.

A)Peptides
B)Catecholamines
C)Steroids
D)Thyroid hormone
E)Corticotropes

Question 32

Which of the following is not shared by both lipophilic and hydrophilic hormones?

A)Amplification of hormone actions in a cell
B)Transport via plasma proteins
C)Regulation of metabolic reactions
D)Initiation of second messenger systems
E)Both b and d

Question 33

Which class of hormones triggers the synthesis of new intracellular proteins within the target cell?

A)peptides
B)catecholamines
C)steroids
D)thyroid hormone
E)c and d

Question 34

Identify all correct statements about lipophilic hormones.

A)They include steroids and thyroid hormone
B)They bind with receptors located inside their target cells
C)They activate second-messenger systems within their target cells
D)Both a and b
E)Both a and c

Question 35

Which of the following situations represents negative feedback?

A)Hormone A stimulates hormone B; hormone B inhibits hormone C.
B)Hormone A inhibits hormone B; hormone B inhibits hormone A.
C)Hormone A stimulates hormone B; hormone B inhibits hormone A.
D)Hormone A inhibits hormone B; hormone B inhibits hormone C.
E)Hormone A stimulates hormone B; hormone B stimulates hormone A.

Question 36

__________ do(es) not use a second messenger system.

A)ACTH
B)Steroid hormones and TH
C)Glucagon
D)Most hydrophilic hormones
E)Only a few lipophilic hormones

Question 37

The effective plasma concentration of a hormone is normally regulated by appropriate adjustments in the hormone's rate of

A)excretion
B)binding to plasma proteins
C)metabolic inactivation
D)secretion
E)binding with target-cell receptors

Question 38

A hormone's effective plasma concentration can be influenced by

A)its rate of excretion
B)its extent of binding to plasma proteins
C)its rate of metabolic inactivation
D)its rate of secretion
E)all of the above

Question 39

Which hormones use second-messenger systems?

A)proteins
B)catecholamines
C)steroids
D)thyroid hormone
E)Both c and d

Question 40

In one kind of second-messenger system,

A)a small amount of one hormone (second messenger) is required to release another
B)a tropic hormone (first messenger) stimulates secretion of another hormone (the second messenger)
C)the hormone binds to a specific surface receptor, whereupon the hormone-receptor complex moves into the cell to combine with an intracellular receptor
D)releasing hormones (first messenger) from the hypothalamus regulate anterior pituitary hormones (second messengers)
E)a hormone (first messenger) binds to surface receptors that activate adenylate cyclase, which then catalyzes cAMP formation

Question 41

Melatonin's actions may include

A)regulation of circadian rhythms
B)antioxidant activity
C)induction of calcium reabsorption
D)both a and b
E)none of the above

Question 42

Which structure(s) is/are neuroendocrine in nature?

A)anterior pituitary
B)posterior pituitary
C)hypothalamus
D)Both a and b
E)Both b and c

Question 43

The posterior pituitary

A)is composed of nervous tissue
B)stores anterior pituitary hormones, which are released into the blood upon hypothalamic stimulation
C)synthesizes and secretes vasopressin and oxytocin
D)is composed of nervous tissue and synthesizes and secretes vasopressin and oxytocin
E)has all of the above characteristics

Question 44

Select the incorrect association.

A)adrenal medulla/vasopressin
B)anterior pituitary/adenohypophysis
C)epinephrine/catecholamine
D)insulin/polypeptide
E)posterior pituitary/neurohypophysis

Question 45

Melatonin is an antioxidant that

A)accelerates metabolism
B)defends against free radicals
C)lowers the concentration of blood sugar
D)serves as a secondary messenger
E)stimulates reduction reactions

Question 46

Which of the following hormones secreted by the anterior pituitary is non-tropic?

A)TSH
B)PRL
C)LH
D)ACTH
E)FSH

Question 47

Synergism occurs when

A)one hormone induces the loss of another hormone's receptors
B)the actions of several hormones are complementary, and their combined effect is greater than the sum of their separate effects
C)one hormone must be present in adequate amounts for the full exertion of another hormone's effect, even though the first hormone does not directly elicit the response
D)one hormone increases the number of target-tissue receptors for another hormone
E)the number of target tissue receptors for a hormone is reduced as a direct consequence of the hormone's effect on its own receptors

Question 48

The posterior pituitary

A)secretes ADH
B)stores anterior pituitary hormones
C)stores ACTH and LH
D)secretes vasopressin and oxytocin into the hypothalamo-hypophyseal portal system
E)does none of the above

Question 49

The anterior pituitary

A)is also known as the neurohypophysis
B)is composed primarily of nervous tissue
C)primarily secretes tropic hormones
D)is both a and b
E)has characteristics b and c

Question 50

Identify the gonadotropic hormone(s).

A)LH
B)FSH
C)Testosterone
D)All of the above
E)Only a and b

Question 51

Which of the following hormones is released from the hypothalamus?

A)CRH
B)TSH
C)FSH
D)LH
E)GH

Question 52

Which of the following is a neurohormone?

A)vasopressin
B)thyroid hormone
C)growth hormone
D)cortisol
E)luteinizing hormone

Question 53

The __________ has a direct anatomical connection to the hypothalamus?

A)adrenal gland
B)posterior pituitary
C)thyroid gland
D)parathyroid gland
E)thymus gland

Question 54

Endocrine disorders resulting in too little hormone activity may stem from all of the following except

A)lack of target cell receptors
B)hyposecretion
C)reduced plasma protein binding
D)increased removal from blood
E)genetic mutations

Question 55

The ________ is the target for ACTH.

A)adrenal gland
B)anterior pituitary
C)posterior pituitary
D)ovary
E)pancreas

Question 56

Melatonin is produced in the

A)anterior pituitary
B)posterior pituitary
C)pineal
D)hypothalamus
E)thyroid

Question 57

With regards to circadian rhythms,

A)the hypothalamus supraoptic nucleus maintains them
B)the suprachiasmatic nucleus is responsible for generating them
C)they are brought about by fluctuating levels of clock proteins
D)both a and b are true
E)both a and c are true

Question 58

Too little activity of a particular hormone can arise from

A)an abnormality within the endocrine gland that produces this hormone
B)a deficiency of this hormone's tropic hormone
C)an inborn lack of target-cell receptors for this hormone
D)deficient target-cell receptors
E)all of the above

Question 59

The ___________ secretes insulin and glucagon.

A)posterior pituitary
B)liver
C)pancreas
D)stomach
E)adrenal medulla

Question 60

Permissiveness of hormones refers to the fact that

A)hormones permit cellular processes to occur
B)hormones permit their target organs to function at the optimal rate
C)in some instances an adequate amount of one hormone must be present for the full exertion of another hormone's effect, even though the first hormone itself does not directly elicit the response
D)the nervous system through numerous neuroendocrine relationships permits the endocrine system to function
E)the tropic hormones permit other endocrine glands to secrete their hormones

Question 61

Which statement about hypophysiotropic hormones is/are correct?

A)Each hormone influences only one anterior pituitary hormone.
B)All of them stimulate the release of anterior pituitary hormones.
C)They are also produced outside of the hypothalamus, where they serve different functions.
D)They are secreted into the general circulation.
E)None of the above

Question 62

Growth hormone

A)levels in the blood are directly correlated with the rate of growth throughout life
B)stimulates the secretion of somatomedins
C)stimulates osteoclast activity more than osteoblast activity
D)does both b and c
E)does none of the above

Question 63

Which of the following hormones is regulated by the anterior pituitary?

A)parathyroid hormone
B)cortisol
C)aldosterone
D)insulin
E)TRH

Question 64

_________ is not an effect of GH.

A)Increased fat breakdown
B)Increased bone growth
C)Decreased glucose entry into muscle cells
D)Decreased protein synthesis
E)Increased rate of cell division

Question 65

_______ is a pituitary hormone that has no role in reproductive physiology.

A)Follicle-stimulating hormone
B)Luteinizing hormone
C)Oxytocin
D)Prolactin
E)Vasopressin

Question 66

Hormones produced in the anterior pituitary are

A)made in distinct populations of cells
B)either tropic or nontropic
C)secreted into the blood
D)released in response to certain hormones
E)all of the above

Question 67

Hormone secretion from the anterior pituitary gland is controlled by

A)hormones from the hypothalamus
B)by neural innervation of anterior pituitary cells
C)negative-feedback action of target-tissue hormones
D)both a and c
E)none of the above

Question 68

Growth hormone

A)increases the uptake of amino acids by cells
B)promotes triglyceride breakdown
C)works with insulin to lower blood sugar
D)does both a and b
E)does both a and c

Question 69

The _________ releases corticotropin in response to _______ from the _______.

A)anterior pituitary; cortisol; hypothalamus
B)hypothalamus; cortisol; adrenal gland
C)adrenal gland; ACTH; anterior pituitary
D)anterior pituitary; CRH; hypothalamus
E)posterior pituitary; corticotropin-releasing hormone; hypothalamus

Question 70

Hypophysiotropic hormones

A)control the release of oxytocin and vasopressin from the posterior pituitary
B)travel via neuron axons from the hypothalamus to the anterior pituitary
C)are carried in the hypothalamo-hypophyseal portal system
D)are released upon positive-feedback stimulation via anterior pituitary tropic hormones
E)always act to stimulate the release of anterior pituitary hormones

Question 71

The hypothalamo-hypophyseal portal system

A)carries anterior pituitary hormones to the hypothalamus to regulate the release of hypophysiotropic hormones
B)diverts blood to the pituitary, completely bypassing the hypothalamus
C)carries hypophysiotropic hormones to the anterior pituitary to regulate anterior pituitary hormone secretion
D)carries anterior pituitary hormones into the general systemic circulation
E)connects the hypothalamus and posterior pituitary

Question 72

Which statement regarding vasopressin is incorrect?

A)It is produced in the hypothalamus.
B)It stimulates uterine smooth muscle contraction.
C)It increases kidney reabsorption of water.
D)It is a potent arteriolar vasoconstrictor.
E)It is released when the osmolarity of the plasma increases.

Question 73

A portal system exists between the

A)adrenal cortex and adrenal medulla
B)hypothalamus and anterior pituitary
C)hypothalamus and posterior pituitary
D)small intestine and liver
E)both b and d

Question 74

__________ is not a characteristic of oxytocin.

A)Stimulating uterine contractions
B)Promoting milk ejection from mammary gland ducts
C)Influencing bonding behavior between mother and baby
D)Being a tropic hormone
E)Being released from the neurohypophysis

Question 75

LH stimulates the

A)cells that destroy the cells of Leydig
B)enlargement of the follicles
C)development of the hypothalamus
D)formation of the corpus luteum
E)water balance in the kidney

Question 76

Growth hormone

A)closes the epiphyseal plate of long bones
B)promotes hypertrophy and hyperplasia
C)secretion is stimulated by an increased blood glucose level
D)is the only factor responsible for governing the growth of an individual
E)has all of the above characteristics

Question 77

__________ is not a function of GH.

A)Increasing uptake of amino acids by cells
B)Stimulating the synthesis of somatomedins
C)Enhancing glucose uptake by muscle cells
D)Stimulating cell division
E)Promoting bone growth

Question 78

________ inhibiting ______ secretion represents a long-loop negative feedback mechanism.

A)Cortisol, CRH
B)CRH, ACTH
C)ACTH, CRH
D)ACTH, cortisol
E)CRH, cortisol

Question 79

________ is the hypothalamic hormone that causes the anterior pituitary to release ____, thus, resulting in thyroid hormone release.

A)Thyroid-releasing hormone; thyroid-stimulating hormone
B)Thyroid stimulating hormone; thyrotropin-releasing hormone
C)Thyrotropin-releasing hormone; thyroid-stimulating hormone
D)Thyroid hormone; thyrotropin-releasing hormone
E)Thyrotropin-releasing hormone; thyroid hormone

Question 80

Which one of the following hormones signals the kidneys to control water balance?

A)vasopressin
B)ACTH
C)TRH
D)somatostatin
E)PIH