Endocrine Flashcards
1
Q
Tumor of the suprarenal gland that liberates excessive androgens, causing virilism (masculinization) in females
A
Virilizing adenoma
2
Q
A severe state of hyperthyroidism that can be life-threatening. It is characterized by high body temperature, rapid heart rate, high blood pressure, digestive canal symptoms (abdominal pain, vomiting, diarrhea), agitation, tremors, confusion, seizures, and possibly coma.
A
Thyroid crisis (storm)
3
Q
Excessive development of mammary glands in a male.
A
Gynecomastia
4
Q
The thyroid gland often decreases its output of thyroid hormones with age, causing a ____ in metabolic rate, an _____ in body fat,
A
decrease; increase
5
Q
With aging, the blood level of PTH _____
A
rises
6
Q
The resultant decreased output of estrogens leads to conditions such as
A
osteoporosis, high blood cholesterol, and atherosclerosis
7
Q
The most common abnormality associated with dysfunction of the posterior pituitary is
A
Diabetes Insipidus
8
Q
due to defects in antidiuretic hormone (ADH) receptors or an inability to secrete ADH; excretion of large volumes of urine, with resulting dehydration and thirst. Bed-wetting is common in afflicted children
A
Diabetes Insipidus
9
Q
types of diabetes Insipidus
A
Neurogenic diabetes insipidus; nephrogenic diabetes insipidus
10
Q
hyposecretion of thyroid hormones that is present at birth, has devastating consequences if not treated promptly. Previously termed cretinism, this condition causes severe mental retardation and stunted bone growth
A
Congenital hypothyroidism
11
Q
Hypothyroidism during the adult years produces _____, which occurs about five times more often in females than in males. A hallmark of this disorder is edema (accumulation of interstitial fluid) that causes the facial tissues to swell and look puff
A
myxedema
12
Q
The most common form of hyperthyroidism; autoimmune disorder in which the person produces antibodies that mimic the action of thyroid-stimulating hormone (TSH).
A
Graves′ disease (ophthalmic hyperthyroidism)
13
Q
Graves′ patients often have a peculiar edema behind the eyes, called
A
exophthalmos
14
Q
leads to a deficiency of blood Ca2+, which causes neurons and muscle fibers to depolarize and produce action potentials spontaneously. This leads to twitches, spasms, and tetany (maintained contraction) of skeletal muscle.
A
tetany
15
Q
An elevated level of PTH causes excessive resorption of bone matrix, raising the blood levels of calcium and phosphate ions and causing bones to become soft and easily fractured.
A
Hyperparathyroidism
15
Q
Hypersecretion of cortisol by the suprarenal cortex produces; characterized by breakdown of muscle proteins and redistribution of body fat, resulting in spindly arms and legs accompanied by a rounded “moon face,” “buffalo hump” on the back, and pendulous (hanging) abdomen
A
Cushing’s syndrome
16
Q
Hyposecretion of glucocorticoids and aldosterone causes; The skin may have a “bronzed” appearance that often is mistaken for a suntan.
A
Addison’s disease (chronic adrenocortical insufficiency).
17
Q
Usually benign tumors of the chromaffin cells of the suprarenal medulla _______ cause hypersecretion of epinephrine and norepinephrine.
A
Pheochromocytomas
18
Q
is a chronic disorder in which the pancreas does not produce sufficient insulin or body cells do not use insulin properly
A
Diabetes mellitus
19
Q
is an autoimmune disease in which insulin level is low because the person’s immune system destroys pancreatic beta cells, the producers of insulin; called insulin-dependent diabetes; juvenile-onset diabetes because it usually occurs in people under 20 years of age
A
type 1 diabetes
20
Q
noninsulin-dependent diabetes or adult-onset diabetes and is the more common type of diabetes and typically occurs in individuals who are over 40 and who are overweight. In these people, body cells become resistant to insulin. As a result, the pancreas has to work harder to produce more insulin. This damages beta cells and therefore insulin production decreases
A
Type 2 diabetes
21
Q
A variety of stressful conditions or noxious agents elicit a similar sequence of bodily changes. These changes, called the
A
stress response or general adaptation syndrome (GAS), are controlled mainly by the hypothalamus
22
Q
The stress response occurs in three stages:
A
(1) an initial fight-or-flight response,
(2) a slower resistance reaction,
(3) exhaustion
23
Q
initiated by nerve impulses from the hypothalamus to the sympathetic part of the autonomic nervous system (ANS), including the suprarenal medulla, quickly mobilizes the body’s resources for immediate physical activity
A
fight-or-flight response
24
nonessential body functions such as digestive, urinary, and reproductive activities are inhibited
fight-or-flight response
25
causes the kidneys to retain Na+, which
leads to water retention and elevated blood pressure
Aldosterone
26
is initiated in large part by hypothalamic releasing hormones and is a longer-lasting response. The hormones involved are corticotropin-releasing hormone (CRH), growth hormone–releasing hormone (GHRH), and thyrotropin-releasing hormone (TRH)
Resistance Reaction
27
stimulates the anterior pituitary to secrete ACTH, which in turn stimulates the suprarenal cortex to increase release of cortisol.
corticotropin-releasing hormone (CRH)
28
stimulates gluconeogenesis by liver cells, breakdown of triglycerides into fatty acids (lipolysis), and catabolism of proteins into amino acids. Tissues throughout the body can use the resulting glucose, fatty acids, and amino acids to produce ATP or to repair damaged cells.
Cortisol
29
causes the anterior pituitary to secrete growth hormone (GH) in liver
growth hormone–releasing hormone
30
stimulates lipolysis and glycogenolysis, the breakdown of glycogen to glucose, in the
liver
insulinlike growth factors
31
stimulates the anterior pituitary to secrete thyroid-stimulating hormone
thyrotropin-releasing hormone
32
promotes secretion of thyroid hormones, which stimulate the increased use of glucose for ATP production
TSH
33
the resistance stage fails to combat the stressor, and the body moves into the state
Exhaustion
34
stimulate the hypothalamus to initiate the stress response through the fight-or-flight response and the resistance reaction
Stressors
35
Stress responses
Lipolysis
Gluconeogenesis
Protein catabolism
Sensitized blood vessels
Reduced inflammation
promoted by cortisol
36
a substance secreted by macrophages of the
immune system, is an important link between stress and immunity. One action of this is to stimulate secretion of ACTH, which in turn stimulates the production of cortisol.
Interleukin-1
37
an anxiety disorder that may develop in an individual who has experienced, witnessed, or learned about a physically or psychologically distressing event
Post-traumatic stress disorder (PTSD)
38
pituitary gland begins to develop from two different regions of the
ectoderm
39
posterior pituitary is derived from an outgrowth of ectoderm called the
neurohypophyseal bud
40
The anterior pituitary is derived from an invagination of ectoderm from the roof of the mouth called the
hypophyseal pouch or Rathke’s pouch.
41
The thyroid gland develops during the fourth week as a midventral outgrowth of endoderm
thyroid diverticulum, from the floor of the pharynx at the level of the second pair of pharyngeal pouches
42
The parathyroid glands develop during the fourth week from endoderm as outgrowths from
third and fourth pharyngeal pouches
43
The suprarenal cortex is derived from the same region of
mesoderm that produces the gonads
44
The suprarenal medulla is derived from
ectoderm from neural crest cells that migrate to the superior pole of the kidney
45
neural crest cells also give rise to
sympathetic ganglia and other structures of the nervous system
46
pancreas develops during the fifth through seventh weeks from two outgrowths of
endoderm from the part of the foregut that later becomes the duodenum
47
The pineal gland arises during the seventh week as an outgrowth between the thalamus and colliculi of the midbrain from
ectoderm associated with the diencephalon
48
The thymus arises during the fifth week from
endoderm of the third pharyngeal pouches
49
Two families of eicosanoid molecules that are found in virtually all body cells except red blood cells, where they act as local hormones (paracrines or autocrines) in response to chemical or mechanical stimuli.
prostaglandins (PGs) and the leukotrienes (LTs)
50
is a modified PG that constricts blood vessels and promotes platelet activation.
Thromboxane (TX)
51
stimulate chemotaxis (attraction to a chemical stimulus) of white blood cells and mediate inflammation
Leukotrienes
52
alter smooth muscle contraction, glandular secretions, blood flow, reproductive processes, platelet function, respiration, nerve impulse transmission, lipid metabolism, and immune responses. They also have roles in promoting inflammation and fever, and in intensifying pain.
prostaglandins
53
found in the skin that plays a role in the synthesis of calcitriol, the active form of vitamin D.
Cholecalciferol
54
Found in the Digestive canal that promotes secretion of gastric juice; increases movements of the stomach.
Gastrin
55
Found in the Digestive canal which stimulates release of insulin by pancreatic beta cells
Glucose- dependent insulinotropic peptide (GIP)
56
Found in the digestive canal which stimulates secretion of pancreatic juice and bile
Secretin
57
Found in the digestive canal which stimulates secretion of pancreatic juice; regulates release of bile from gallbladder; causes feeling of fullness after eating
Cholecystokinin (CCK)
58
In the placenta: Stimulates corpus luteum in ovary to continue production of estrogens and progesterone to maintain pregnancy.
Human chorionic gonadotropin (hCG)
59
In the placenta: Maintain pregnancy; help prepare mammary glands to secrete milk.
Estrogens and progesterone
60
In the placenta: Stimulates development of mammary glands for lactation.
Human chorionic somatomammotropin (hCS)
61
From the kidneys: Part of reaction sequence that raises blood pressure by bringing about
vasoconstriction and secretion of aldosterone.
Renin
62
From the kidneys: Increases rate of red blood cell formation.
Erythropoietin (EPO)
63
From the kidneys: Aids in absorption of dietary calcium and phosphorus
Calcitriol
64
From the heart: Decreases blood pressure.
atrial natriuretic peptide (ANP)
65
from the adipose tissue: Suppresses appetite; may increase FSH and LH activity
Leptin
66
inhibit cyclooxygenase (COX), a key enzyme involved in prostaglandin synthesis
Aspirin and related nonsteroidal anti- inflammatory drugs (NSAIDs), such as ibuprofen (Motrin®)
67
GF: Produced in submaxillary (salivary) glands; stimulates proliferation of epithelial cells, fibroblasts, neurons, and astrocytes; suppresses some cancer cells and secretion of gastric juice by stomach
Epidermal growth factor (EGF)
68
GF: Produced in blood platelets; stimulates proliferation of neuroglia, smooth muscle fibers, and fibroblasts; appears to have role in wound healing; may contribute to atherosclerosis development
platelet- derived growth factor (PDGF)
69
GF: Found in pituitary gland and brain; stimulates proliferation of many cells derived from embryonic mesoderm (fibroblasts, adrenocortical cells, smooth muscle fibers, chondrocytes, and endothelial cells); stimulates formation of new blood vessels (angiogenesis).
Fibroblast growth factor (FGF)
70
GF: Produced in submandibular (salivary) glands and hippocampus of brain; stimulates growth of ganglia in embryo; maintains sympathetic nervous system; stimulates hypertrophy and differentiation of neurons.
Nerve growth factor (NGF)
71
Produced by normal and tumor cells; stimulate growth of new capillaries, organ regeneration, and wound healing.
tumor angiogenesis factors (TAFs)
72
Produced by various cells as separate molecules: TGF- alpha has activities similar to epidermal growth factor; TGF- beta inhibits proliferation of many cell types.
transforming growth factors (TGFs)
73
Together with gonadotropic hormones of anterior pituitary (LH and FSH), regulate female reproductive cycle, maintain pregnancy, prepare mammary glands for lactation, and promote development and maintenance of female secondary sex characteristics.
Estrogens and progesterone
74
Increases flexibility of pubic symphysis during pregnancy; helps dilate uterine cervix during labor and delivery.
Relaxin
75
Inhibits secretion of FSH from anterior pituitary.
Inhibin
76
Stimulates descent of testes before birth; regulates sperm production; promotes development and maintenance of male secondary sex characteristics.
testosterone
77
Inhibits secretion of FSH from anterior pituitary.
Inhibin
78
a small endocrine gland attached to the roof of the third ventricle of the brain at the midline
pineal gland
79
The gland consists of masses of neuroglia and secretory cells called
pinealocytes
80
appears to contribute to the setting of the body’s biological clock, which is controlled by the suprachiasmatic nucleus of the hypothalamus
Melatonin
81
is a type of depression that afflicts some people during the winter months, when day length is short. It is thought to be due, in part, to overproduction of melatonin.
Seasonal affective disorder (SAD)
82
Roughly 99% of the cells of the pancreas are
exocrine cells arranged in clusters called___; produce digestive enzymes, which flow into the digestive canal through a network of ducts.
pancreatic acini
83
is both an endocrine gland and an exocrine gland.
pancreas
84
Scattered among the pancreatic acini are 1–2 million tiny clusters of endocrine cells called
pancreatic islets
85
constitute about 17% of pancreatic islet cells and secrete glucagon
alpha or A cells
86
constitute about 7% of pancreatic islet cells and secrete somatostatin
Delta or D cells
86
constitute about 70% of pancreatic islet cells and secrete insulin
Beta or B cells
86
constitute the remainder of pancreatic islet cells and secrete pancreatic polypeptide
pancreatic polypeptide cells
87
acts in a paracrine manner to inhibit both insulin and glucagon release from neighboring beta and alpha cells. It may also act as a circulating hormone to slow absorption of nutrients from the gastrointestinal tract; inhibits the secretion of growth hormone
Somatostatin
88
inhibits somatostatin secretion, gallbladder contraction, and secretion of digestive enzymes by the pancreas.
pancreatic polypeptide
89
The level of blood glucose controls secretion of glucagon and insulin
negative feedback
90
Glucagon acts on hepatocytes (liver cells) to accelerate the conversion of glycogen into glucose
glycogenolysis
91
formation of glucose from lactic acid and certain amino acids
gluconeogenesis
92
glycogen to glucose
glycogenolysis
93
glucose into glycogen
glycogenesis
94
Insulin secretion is also stimulated by
Acetylcholine
The amino acids arginine and leucine
Glucose- dependent insulinotropic peptide (GIP)
95
Glucagon secretion is stimulated by
Increased activity of the sympathetic part of the ANS, as occurs during exercise
rise in blood amino acids if blood glucose level is low
96
indirectly stimulate secretion of insulin because they act to elevate blood glucose.
growth hormone (GH) and adrenocorticotropic hormone
97
Control of Secretion: Decreased blood level of glucose, exercise, and mainly protein meals stimulate secretion; somatostatin and insulin inhibit secretion.
Glucagon
98
Principal Action: Raises blood glucose level by accelerating breakdown of glycogen into glucose in liver (glycogenolysis), converting other nutrients into glucose in liver (gluconeogenesis), and releasing glucose into blood.
Glucagon
99
Cell Types in the Pancreatic Islets
Alpha
Beta
Delta
F cells
100
Control of Secretion: Increased blood level of glucose, acetylcholine (released by parasympathetic vagus nerve fibers), arginine and leucine (two amino acids), glucagon, GIP, GH, and ACTH stimulate secretion; somatostatin inhibits secretion.
Insulin
101
Principal actions: Lowers blood glucose level by accelerating transport of glucose into cells, converting glucose into glycogen (glycogenesis), and decreasing glycogenolysis and gluconeogenesis; increases lipogenesis and stimulates protein synthesis.
Insulin
102
Control of Secretion: Pancreatic polypeptide inhibits secretion
Somatostatin
103
Principal action: Inhibits secretion of insulin and glucagon; slows absorption of nutrients from digestive canal.
Somatostatin
104
Control of Secretion: Meals containing protein, fasting, exercise, and acute hypoglycemia stimulate secretion; somatostatin and elevated blood glucose level inhibit secretion.
pancreatic polypeptide
105
Principal Action: Inhibits somatostatin secretion, gallbladder contraction, and secretion of pancreatic digestive enzymes.
pancreatic polypeptide
106
comprising 80–90% of the supradrenal gland
suprarenal cortex
107
produces steroid hormones that are essential for life.
suprarenal cortex
108
produces three catecholamine hormones— norepinephrine, epinephrine, and a small amount of dopamine
suprarenal medulla
109
suprarenal cortex is subdivided into three zones
zona glomerulosa
zona fasciculata
zona reticularis
110
secrete hormones called mineralocorticoids; affect mineral homeostasis.
zona glomerulosa
111
secrete mainly glucocorticoids; affect glucose
homeostasis
zona fasciculata
112
synthesize small amounts of weak androgens
zona reticularis
113
major mineralocorticoid. It regulates homeostasis of two mineral ions— namely, sodium ions (Na+) and potassium ions (K+)—and helps adjust blood pressure and blood volume. Also promotes excretion of H+ in the urine; this removal of acids from the body can help prevent acidosis (blood pH below 7.35)
aldosterone
114
controls secretion of aldosterone
renin–angiotensin–aldosterone (RAA) pathway
115
Stimuli that initiate the renin–angiotensin–aldosterone pathway
dehydration, Na+deficiency, or hemorrhage
116
Lowered blood pressure stimulates certain cells of the kidneys, called juxtaglomerular cells, to secrete the enzyme
renin
117
As blood flows through capillaries, particularly those of the lungs, the enzyme angiotensin-converting enzyme (ACE)converts angiotensin I
angiotensin II
118
stimulates the suprarenal cortex to secrete
aldosterone
angiotensin II
119
With increased water reabsorption by the kidneys, blood volume
increases
120
Glucocorticoids have the following effects
Protein breakdown
Glucose formation
Lipolysis
Resistance to stress
Anti- inflammatory effects
Depression of immune responses
121
For this reason, glucocorticoids are prescribed for organ transplant recipients to retard tissue rejection by the immune system
Depression of immune responses
122
Control of glucocorticoid secretion occurs via a typical
negative feedback system
123
Low blood levels of glucocorticoids, mainly cortisol, stimulate neurosecretory cells in the hypothalamus to secrete
corticotropin- releasing hormone (CRH)
124
major androgen secreted by the suprarenal gland is
dehydroepiandrosterone (DHEA)
125
A high level of CRH and a low level of glucocorticoids promote the release
ACTH
126
stimulate growth of axillary and pubic hair in boys and girls and contribute to the prepubertal growth spurt.
Suprarenal androgens
127
genetic disorder in which one or more enzymes needed for synthesis of cortisol are absent. Because the cortisol level is low, secretion of ACTH by the anterior pituitary is high due to lack of negative feedback inhibition. ACTH in turn stimulates growth and secretory activity of the suprarenal cortex. As a result, both suprarenal glands are enlarged.
Congenital adrenal hyperplasia (CAH)
128
The inner region of the suprarenal gland s a modified sympathetic ganglion of the autonomic nervous system (ANS).
suprarenal medulla
129
The hormone-producing cells, called___ are are innervated by sympathetic preganglionic neurons of the ANS
chromaffin cells
130
The two major hormones synthesized by the suprarenal medulla are
epinephrine and norepinephrine (NE)
131
Control of Secretion: Increased blood K+
level and angiotensin II stimulate secretion.
Mineralocorticoids (mainly aldosterone)
132
principal actions: Increase blood levels of Na+
and water; decrease blood level of K+
Mineralocorticoids (mainly aldosterone)
133
Control of Secretion: ACTH stimulates release; corticotropin releasing hormone (CRH) promotes ACTH secretion in response to stress and low blood levels of glucocorticoids.
Glucocorticoids (mainly cortisol)
134
principal actions: Increase protein breakdown (except in liver), stimulate gluconeogenesis and lipolysis, provide resistance to stress, dampen inflammation, depress immune responses.
Glucocorticoids (mainly cortisol)
135
Control of Secretion: ACTH stimulates secretion
androgens (mainly dehydroepiandrosterone, or DHEA)
136
principal actions: Assist in early growth of axillary and pubic hair in both sexes; in females, contribute to libido and are source of estrogens after menopause.
androgens (mainly dehydroepiandrosterone, or DHEA)
137
Suprarenal cortex hormones
Mineralocorticoids (mainly aldosterone)
Glucocorticoids (mainly cortisol)
Androgens (mainly dehydroepiandrosterone, or DHEA)
138
Suprarenal medulla hormones
Epinephrine and norepinephrine
139
CoS: Sympathetic preganglionic neurons release acetylcholine, which stimulates secretion.
Epinephrine and norepinephrine
140
PA: Enhance effects of sympathetic part of autonomic nervous system during stress
Epinephrine and norepinephrine
141
from dense principal parathyroid cells
parathyroid hormone (PTH)
142
CoS: Low blood Ca2+ levels stimulate secretion; high blood Ca2+ levels inhibit secretion.
PTH
142
PA: Increases blood Ca2+ and Mg2+ levels and
decreases blood HPO42− level; increases bone resorption by osteoclasts; increases Ca2+ reabsorption and HPO42− excretion by kidneys; promotes formation of calcitriol (active form of vitamin D), which increases rate of dietary Ca2+ and Mg2+ absorption.
PTH
143
few cells called C thyrocytes (parafollicular cells) produces
calcitonin
144
CS: Secretion is increased by thyrotropin-releasing hormone (TRH), which stimulates release of thyroid- stimulating hormone (TSH) in response to low thyroid hormone levels, low metabolic rate, cold, pregnancy, and high altitudes; TRH and TSH secretions are inhibited in response to high thyroid hormone levels; high iodine level suppresses T3/T4 secretion.
T3 (triiodothyronine) and T4 (thyroxine) or thyroid hormones from follicular cells
145
PA: Increase basal metabolic rate; stimulate synthesis of proteins; increase use of glucose and fatty acids for ATP production; increase lipolysis; enhance cholesterol excretion; accelerate body growth; contribute to development of nervous system
T3 (triiodothyronine) and T4 (thyroxine) or thyroid hormones from follicular cells
146
CS: High blood Ca2+ levels stimulate secretion; low blood Ca2+ levels inhibit secretion.
Calcitonin (CT)
147
PA: Lowers blood levels of Ca2+ and HPO42− by inhibiting bone resorption by osteoclasts and by accelerating uptake of calcium and phosphates into bone extracellular matrix
Calcitonin (CT)
148
As cells produce and use more ATP, BMR increases, more heat is given off, and body temperature rises, a phenomenon called the
calorigenic effect
149
CS: Neurosecretory cells of hypothalamus secrete OT in response to uterine distension and stimulation of nipples.
Oxytocin (OT)
150
PA: Stimulates contraction of smooth muscle cells of uterus during childbirth; stimulates contraction of myoepithelial cells in mammary glands to cause milk ejection
Oxytocin (OT)
151
CS: Neurosecretory cells of hypothalamus secrete ADH in response to elevated blood osmotic pressure, dehydration, loss of blood volume, pain, or stress; inhibitors of ADH secretion include low blood osmotic pressure, high blood volume, and alcohol
antidiuretic hormone (ADH) or vasopressin
152
PA: Conserves body water by decreasing urine volume; decreases water loss through perspiration; raises blood pressure by constricting arterioles
antidiuretic hormone (ADH) or vasopressin
153
posterior pituitary hormones
OT and ADH
154
The neuronal cell bodies of both the paraventricular and the supraoptic nuclei synthesize the hormones
OT and ADH
155
The axon terminals in the posterior pituitary are associated with specialized neuroglia called
pituicytes
156
Blood is supplied to the posterior pituitary by the
Inferior hypophyseal arteries, which branch from the internal carotid arteries.
157
In the posterior pituitary, the inferior hypophyseal arteries drain into the
capillary plexus of the infundibular stalk
158
FIVE types of anterior pituitary cells
somatotrophic cells
thyrotrophic cells
gonadotrophic cells,
prolactin cells
corticotrophic cells
159
epinephrine alone only weakly stimulates lipolysis (the breakdown of triglycerides), but when small amounts of thyroid hormones (T3
and T4) are present, the same amount of epinephrine stimulates lipolysis much more powerfully
permissive effect
160
target cells require a simultaneous or recent exposure to a second hormone
permissive effect
161
both glucagon and epinephrine increase the blood glucose concentration by stimulating the breakdown of glycogen in liver cells. When both hormones are present, the increase in blood glucose concentration is greater than the sum of the individual hormone responses.
synergistic effect
162
bind to receptors that protrude from the target-cell surface. The receptors are integral transmembrane proteins in the plasma membrane
water-soluble hormones
163
bind to receptors within target cells
Lipid-Soluble Hormones
164
Lipid-Soluble Hormones
steroid hormones
thyroid hormones
nitric oxide
eicosanoid hormones
165
The water-soluble hormones
amine hormones
protein and peptide hormones
