endocrine system 2 Flashcards
week 1 (139 cards)
1
Q
the hypothalamus is connected to the pituitary gland by a stalk called the —
A
infundibulum
2
Q
the posterior pituitary lobe is composed of — tissue that secretes —
A
neural; neurohormones
3
Q
the anterior pituitary lobe is composed of — tissue; called the —
A
glandular; adenohypophysis
4
Q
the hypophyseal portal system vascularly connects the — to the —
A
anterior lobe; hypothalamus
5
Q
the hypophyseal portal system includes the —, —, and —
A
primary capillary plexus, hypophyseal portal veins, and secondary capillary plexus
6
Q
why is the the hypophyseal portal system important?
A
it allows for efficient hormone signaling and regulation between the hypothalamus and anterior pituitary gland
7
Q
the hypothalamic-hypophyseal tract is a bundle of nerve fibers that connects the — to the —
A
hypothalamus; posterior pituitary gland
8
Q
why is the hypothalamic-hypophyseal tract important?
A
enables the direct release of oxytocin and ADH (hormones) into the bloodstream to regulate functions like water balance, childbirth, and lactation.
9
Q
paraventricular neurons produce —
supraoptic neurons produce —
A
oxytocin; ADH
10
Q
hormones are stored in —, they are released into the blood when neurons fire
A
axon terminals
11
Q
— is released during childbirth and is a strong stimulant of contractions
A
oxytocin
12
Q
oxytocin should be associated with — feedback mechanisms
A
positive
13
Q
oxytocin acts as a — in the brain
A
neurotransmitter
14
Q
oxytocin uses the — second messenger system
A
PIP2-calcium
15
Q
when concentration is too high, the —is triggered to secrete —
A
posterior pituitary; ADH
16
Q
high concentrations of vasopressin lead to —
A
vasoconstriction
17
Q
ADH acts to inhibit urine formation by promoting water reabsorption in the —–, helping to prevent —.
A
kidneys; dehydration
18
Q
release of ADH is triggered by —, —, and —
A
pain; low blood pressure; drugs
19
Q
release of ADH it is inhibited by — and —
A
alcohol; diuretics
20
Q
what are diuretics?
A
substances or medications that promote the production of urine, helping the body get rid of excess salt and water
21
Q
All six anterior pituitary hormones are peptides, with all except the — hormone using the cAMP pathway
A
growth
22
Q
what do tropic hormones (tropins) regulate?
A
the secretion of other hormones
23
Q
what are the 6 hormones of the anterior pituitary?
A
- Growth Hormone (GH)
- Thyroid-Stimulating Hormone (TSH)
- Adrenocorticotropic Hormone (ACTH)
- Follicle-Stimulating Hormone (FSH)
- Luteinizing Hormone (LH)
- Prolactin (PRL)
24
Q
growth hormone is also called —. It is produced by — cells.
A
somatotropin; somatotrophic
25
GH has direct actions on --- and indirect actions on ---
metabolism; growth-promoting
26
what three direct actions does GH have on metabolism?
1. reduces glucose and metabolism use by cells
2. stimulates the liver to release glucose from stored glycogen.
3. increases blood fatty acids for energy and supports protein building.
27
what three direct actions does GH have on growth?
1. stimulates the liver, muscles, and bones to produce insulin-like growth factors.
2. insulin-like growth factors help cells absorb nutrients for DNA and protein production, supporting cell growth, bone formation, and collagen production.
3. growth hormone makes cells grow and divide, especially in bones and muscles.
28
the release or inhibition of GH is regulated by two hypothalamic hormones, what are they?
growth hormone-releasing hormone (GHRH) and growth hormone-inhibiting hormone (GHIH)
29
growth hormone-releasing hormone --- GH
stimulates
30
growth hormone-releasing hormone --- GH
inhibits
31
the highest amounts of GH are secreted during ---
sleep
32
GHRH is triggered by low --- or --- levels
blood GH; glucose
33
GHIH is triggered by increased levels of --- and ---
GH, IGF
34
Release of GH is also stimulated by --- – the hunger hormone
ghrelin
35
thyroid-stimulating hormone (TSH) is a --- hormone. It is also called ---. It is produced by --- cells.
tropic; thyrotropin; thyrotropic
36
TSH stimulates normal development and secretory activity of the ---
thyroid gland
37
release of TSH is triggered by secretion of thyrotropin-releasing hormone (TRH) from the ---
hypothalamus
38
TSH is inhibited by high levels of --- hormones in the blood and --- hormone
thyroid; growth hormone-inhibiting
39
adrenocorticotropic hormone (ACTH) is also called --- and is secreted by --- cells.
corticotropin; corticotropic.
40
ACTH stimulates the adrenal cortex to release ---
corticosteroids
41
Follicle-Stimulating Hormone (FSH) + Luteinizing Hormone (LH) are secreted by the --- cells of the anterior pituitary
gonadotropic
42
FSH stimulates the production of --- (egg or sperm)
gametes
43
In females, LH helps to mature egg-containing follicles, triggers ovulation, create and release --- + ---
estrogen; progesterone
44
In males, LH stimulates the production of ---
testosterone
45
During and after puberty, FSH and LH are triggered by --- from the hypothalamus
gonadotropin-releasing hormone (GnRH)
46
prolactin (PRL) is secreted by --- cells in the --- pituitary
prolactin; anterior
47
what does prolactin stimulate in females?
milk production
48
regulation of prolactin is primarily controlled by --- AKA dopamine
prolactin-inhibiting hormone (PIH)
49
decreased levels of PIH leads to ---
lactation
50
what's the reason for breast swelling and tenderness during menstruation?
prolactin levels rise and fall in rhythm with estrogen
51
blood levels of PRL dramatically --- at the end of pregnancy
rise
52
what is the largest pure endocrine gland in the body?
the thyroid gland
53
where is the thyroid gland located?
on the trachea, just inferior to the larynx.
54
what are the four parts of the thyroid gland?
1. isthmus
2. follicles
3. colloid
4. parafollicular cells
55
what hormone do parafollicular cells produce?
calcitonin
56
thyroid hormone is stored extracellularly in the ---
follicle lumen
57
thyroid hormone is found in two forms, what are they?
thyroxine (T4) and triiodothyronine (T3)
58
what's the difference between thyroxine (T4) and triiodothyronine (T3)?
thyroxine (T4) has 4 bound iodine atoms whereas triiodothyronine (T3) has 3 bound iodine atoms
59
at the tissue level, --- must be converted to ---
T3; T4
60
thyroid hormone regulates --- and ---, while maintaining ---
tissue growth; development; blood pressure
61
calcitonin is produced by the --- in response to --- Ca2+ levels
parafollicular cells; high
62
calcitonin is an antagonist to parathyroid hormone (PTH). calcitonin --- calcium, while PTH --- it.
lowers; raises
63
what three things happen when calcitonin's level is elevated?
1. osteoclast activity is inhibited
2. the release of Ca2+ from bone matrix is prevented
3. the uptake of Ca2+ by bone matrix is stimulated
64
where is the parathyroid gland?
The parathyroid gland is located on the posterior (back) side of the thyroid gland, usually 4 to 8 small, yellow-brown glands.
65
the parathyroid gland contains --- and --- cells
oxyphil; parathyroid
66
parathyroid cells secrete ---- hormone
parathyroid hormone (PTH)
67
PTH is the most important hormone in ---
Ca2+ homeostasis
68
PTH’s target organs are the ---, ---, and ---
skeleton, kidneys, and intestines
69
what are three functions of the PTH?
1. stimulate bone breakdown, releasing calcium into the blood.
2. increase calcium reabsorption and phosphate excretion by the kidneys.
3. activate vitamin D in the kidneys, boosting calcium absorption in the intestines.
70
where is the adrenal gland located?
on top of the kidneys
71
what is the difference between the adrenal cortex and the adrenal medulla?
the adrenal cortex is made of glandular tissue, the adrenal medulla is made of nervous tissue
72
the adrenal cortex secretes ---, the adrenal medulla secretes ---
corticosteroids; catecholamines
73
true or false: steroid hormones are not stored in cells
true
74
the 3 layers of cortical cells produce different types of corticosteroids.
zona glomerulosa produces ---,
zona fasciculata produces ---,
zona reticularis produces ---.
mineralocorticoids; glucocorticoids; gonadocorticoids
75
what is the strongest mineralocorticoid?
aldosterone
76
aldosterone stimulates reabsorption of --- by the kidneys, which results in increased blood volume and pressure. it also stimulates elimination of K+ by the kidneys
Na+; K+
77
Atrial Natriuretic Peptide (ANP) tells the body to --- Na+
release
78
glucocorticoids influence the metabolism of most --- and help us to resist ---
cells; stressors
79
glucocorticoids work to keep blood glucose levels relatively ---
constant
80
glucocorticoids maintain blood pressure by increasing the activity of ---
vasoconstrictors
81
what are three glucocorticoid hormones?
Cortisol (Hydrocortisone)
Cortisone
Corticosterone
82
what is the only glucocorticoid made in significant amounts in humans ?
cortisol
83
Cortisol is released in response to ---
ACTH
84
ACTH is released in response to ---
corticotropin-releasing hormone (CRH)
85
CRH is released when cortisol levels are ---. Increased cortisol levels inhibit both --- and ---
low; ACTH; CRH
86
cortisol secretion cycles are governed by our patterns of --- and ---
eating; physical activity
87
the --- can override cortisol’s inhibition of ACTH and CRH leading to more cortisol secretion
central nervous system
88
what is Cushing's disease?
a condition where the body produces too much cortisol, causing symptoms like weight gain, high blood pressure, and muscle weakness.
89
what is Addison's disease?
a disorder where the adrenal glands don't produce enough cortisol, causing symptoms like fatigue, weight loss, low blood pressure, and darkened skin.
90
--- disease is characterized by having a "buffalo hump" of fat on the upper back
Cushings
91
--- disease causes a year-round sun tan
Addisons
92
cortisol increases levels of ---, ---, and --- in the blood
glucose; fatty acids; amino acids
93
--- is one of cortisol's key functions, where the body makes more sugar (glucose) from fats and proteins, giving energy to the brain while encouraging other cells to use fat for energy instead of glucose.
gluconeogenesis
94
cortisol enhances --- to elevate --- quickly and distribute nutrients to ---
vasoconstriction; BP; cells
95
--- are weak androgens (male sex hormones)
gonadocorticoids
96
two examples of gonadocorticoids?
androstenedione and dehydroepiandrosterone (DHEA)
97
gonadocorticoids are converted to --- and some --- in the tissue cells
testosterone; estrogen
98
what are the three functions of gonadocorticoids?
1. Help control the timing of puberty and the development of traits like body hair and voice changes.
2. Regulate sex drive in women
3. Provide a source of estrogens in postmenopausal women
99
medullary chromaffin cells synthesize ---
catecholamines
100
what are two examples of catecholamines?
epinephrine and norepinephrine
101
some effects of catecholamines include --- , increased --- and ---, and
redirecting blood to the ---, ---, and ---
vasoconstriction; heart rate; blood glucose levels ; brain; heart; skeletal muscles
102
epinephrine mainly boosts ---, while norepinephrine focuses more on --- blood vessels and --- blood pressure.
metabolism; narrowing; increasing
103
pinealocytes secrete --- which is a hormone derived from ---
melatonin; serotonin
104
melotonin may affect what four things?
1. the timing of sexual maturity and puberty
2. day/night cycles
3. the physiological processes that slow rhythmic variations – body temperature, sleep, appetite
4. production of antioxidants and detoxification molecules
105
--- contains both exocrine and endocrine cells
the pancreas
106
acinar cells are --- cells that produce the enzyme-rich juice needed for ---
exocrine; digestion
107
pancreatic islets contain --- cells
endocrine
108
--- cells produce glucagon
alpha
109
--- cells produce insulin
beta
110
glucagon is triggered by decreased ---, rising --- levels, or the --- system
blood glucose; amino acid; sympathetic nervous
111
how does glucagon target the liver to raise blood glucose levels?
1. breaks down glycogen to glucose (glycogenolysis)
2. synthesizes glucose from lactic acid and other noncarbohydrates (gluconeogenesis)
3. releases glucose into the blood
112
insulin is secreted when --- levels increase
blood glucose
113
how does insulin lower blood glucose levels?
1. enhances membrane transport of glucose into fat and muscle cells
2. inhibits the breakdown of glycogen to glucose
3. inhibits the conversion of amino acids or fats to glucose
114
Insulin is not needed for glucose uptake by the ---, ---, or ---
liver; kidneys; brain
115
--- produce the same steroid sex hormones as the adrenal cortex – just in lesser amounts
gonads
116
--- produce estrogens and progesterone
ovaries
117
--- helps mature the reproductive organs, triggers secondary sex traits like body hair, and works with progesterone to develop breasts and control changes in the uterus.
estrogen
118
--- produce testosterone
testes
119
--- helps develop and maintain reproductive organs, triggers secondary sex traits like facial hair, and is needed for sperm production.
testosterone
120
the placenta secretes ---, ---, and ---
estrogens; progesterone; human chorionic gonadotropin (hCG)
121
adipose tissue secretes ---, ---, and ---
leptin; resistin; adiponectin
122
what is leptin's role in the body?
helps control appetite and boosts energy use in the body.
123
what is resistin's role in the body?
works against the effects of insulin.
124
what is adiponectin's role in the body?
enhances the body's response to insulin.
125
the gastrointestinal tract secretes ---, ---, ---, ---, and ---
gastrin; ghrelin; secretin; cholecystokinin; incretins.
126
what is gastrin's role in the body?
triggers the release of stomach acid (HCl).
127
what is ghrelin's role in the body?
stimulates hunger and increases food intake.
128
what is secretin's role in the body?
help the liver make bile and the pancreas release fluids that neutralize stomach acid.
129
what is cholecystokinin's role in the body?
stimulates or triggers the pancreas, gallbladder, and hepatopancreatic sphincter to do their specific jobs:
130
what is incretin's role in the body?
boost insulin release and reduce glucagon production
131
the heart releases ---
Atrial Natriuretic Peptide (ANP):
132
what is Atrial Natriuretic Peptide's (ANP's) role in the body?
to decrease concentration of Na+ in the blood and therefore decrease blood pressure and volume
133
the kidneys secrete ---
and ---
erythropoietin; renin
134
what is role of erythropoietin in the body?
it triggers production of red blood cells
135
what is role of renin in the body?
it initiates the renin-angiotensin-aldosterone mechanism
136
--- is a hormone secreted by --- (bone cells) in the skeleton
osteocalcin; osteoblasts
137
osteocalcin stimulates the pancreas to release more ---, improve --- handling, and reduce ---
insulin; glucose; body fat
138
what is the thymus?
a large organ in infants, shrinks with age
139
the thymus produces hormones like ---, ---, and ---, which are important for the development of T-lymphocytes, crucial cells in the immune system.
thymulin; thymopoietins; thymosins
