Which type of chemical messenger, when released, binds to receptors on the cell that released the chemical messenger?
autocrine
Which type of chemical messenger, when released, binds to receptors on a neighboring cell?
paracrine
Where is a systemic hormone released?
into the blood stream
What system does a cytokine contribute to?
Immune - cytokines are active in the immune response
Neurohormones are released into the _______ from _______
blood ; interneurons
Quick fact : Steroid hormones usually have something to do with _______
the nucleus
The opening or closing of fast ligand-gated channels describes a _____ hormone
peptide
The activation of an enzyme-linked receptor describes a ____ hormone
peptide
The ______of the cAMP second messenger system describes a peptide hormone
activation
Altering the transcription of mRNA describes what type of hormone?
a steroid hormone (estrogen)
Where is the Pars tuberalis located and what hormone(s) does it produce?
located in the pituitary stock ; does not produce hormones
What 6 hormones are produced by the Pars distalis of the pituitary?
GH, LH, FSH, prolactin, ACTH, TSH
What 2 hormones are produced by the Pars nervosa of the pituitary?
vasopressin and oxytocin
What is the median eminence responsible for in the pituitary?
capillary action
What hormone is produced by the Pars intermedia of the pituitary?
melanocyte-stimulating hormone (MSH)
The rate limiting enzyme of melatonin synthesis is _____
N-acetyltransferase
Hydroxyindole-O-methyltransferase is part of the second step of ______ synthesis
melatonin
Sporadic melatonin secretion is most likely due to _____
sporadic light cues
If melatonin secretion is inhibited there is ______ light
constant light
The SCN runs on a _____ hour clock
25 hr
In constant darkness, the SCN is ______
activated
In constant darkness for several days, melatonin secretion shows a ________
circadian rhythm - (a 25hr circadian rhythm due to the SCN)
If you remove the ____ , then melatonin is not produced but the SCN can still receive significant light cues
PVN
No PVN = ___________
No PVN = no melatonin from the pineal gland
Melatonin is slightly produced by the ____ and ____ . This melatonin is _____ entrained by the SCN.
GI and eye retina ; still entrained
If the optic tract is ablated, then melatonin production is ______
rhythmic
No SCN = ______________
No SCN = no circadian rhythm
The SCN is responsible for _________
driving circadian rhythm
The PVN is responsible for _________
regulating melatonin production
The epidydimal ducts are responsible for __________
the maturation of sperm
What is the chorionic villi?
forms the membrane between the mother and fetus
In females, the Mullerian ducts ______ as a result of apoptosis
develop
What are the seminiferous ducts responsible for?
sperm generation
In females, the Wolffian ducts ____ as a result of apoptosis
atrophy
In males, androgens (testosterone) are made by _______ cells
Leydig
In females, _____ cells have receptors for LH and produce androgens
thecal
In females, _________ stimulates granulosa cells to convert _____ to ______
FSH ; androgens to estradiol
Estrogen production in ovarian follicles involves ________
both thecal and granulosa cells
Estrogen production is mainly controlled by what 2 hormones?
LH and FSH
What enzyme converts testosterone to DHT?
5alpha-reductase
Estrogen production is ________ just prior to ovulation
increased
Estrogen production in ovarian follicles requires the synthesis of androgens in ____ cells
thecal
Aromatase and 5alpha-reductase act on what hormone?
testosterone
FSH and LH are secreted by what major cell?
the gonadotrope
Gonadotropes are endocrine cells in the anterior pituitary that produce the gonadotropins, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) and is regulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus.
Collagenase os secreted by the ______ follicle
mature
Ghrelin is related to what sensation?
hunger
What does somatostatin do?
inhibits GH
What is the major role of calcitonin?
it inhibits calcium release from bone to blood
______ was recently discovered and has been implicated in reproduction
kisspeptin
The SRY gene produces __________ and causes _____ development
testes determining factor ; testicular
The Wolfian duct develops in ________ while the Mullerian duct develops in _________
Wolffian = males
Mullerian = females
Hashimoto's is a autoimmune disease associated with ________
HYPOthyroidism
Adduson's disease is associated with __________
adrenal deficiency
Cushing's disease is often associated with high _____
cortisol
Graves' disease is due to __________
HYPERthyroidism
Surgical removal of the adrenals often leads to _____ disease
Nelson's
T/F - Thyroid hormones are water soluble, which explains why they pass through cell membranes easily
FALSE
Tri-iodothyronine (T3) has a strong ______ effect on TRH secretion
inhibitory
_______ are due to iodine deficiency, increased iodine demand, or _______ deficiency
Goiters ; selenium
T/F - Cortisol levels remain constant throughout the day
FALSE
Excess ______ causes skin discoloration in Addison's disease
ACTH
Iodide is converted to iodine by the activity of __________
thyroid peroxidase (TPO)
Iodine is actively exchanged with ____ at the luminal surface of the follicular cell
sodium
Thyroxine (T4) is synthesized in _______ amounts than tri-iodothyronine (T3)
greater
T3 is (more/less) active than T4
MORE
_______ is an essential element involved in thyroid hormone metabolism
selenium
Cortisol has an affinity for the aldosterone receptor (more/less/equal) to that of aldosterone
EQUAL - cortisol competes with aldosterone
Aldosterone is secreted by the ____ layer of the adrenals
zona glomerulosa (outer)
Cortisol is secreted by the ____ layer of the adrenals
zona fasciculata (middle)
Androgen is secreted by the ____ layer of the adrenals
zona reticularis (inner)
The middle layer of the adrenals is called the zona _______
fasciculata
The outer layer of the adrenals is called the zona ____
glomerulosa
The inner layer of the adrenals is called the zona ______
reticularis
Angiotensinogen is converted to angiotensin by _____
RENIN
Aromatase converts ______ into _______
testosterone into estrogen
Angiotensin-I is converted to Angiotensin-II by ________
angiotensin-converting enzyme
__________ is responsible for the reuptake of sodium and the secretion of potassium
aldosterone
What ion does parathyroid hormone help regulate?
calcium
Excess aldosterone secretion will lead to elevated plasma levels of ______
sodium
What happens if TPO is inhibited?
iodide is not converted to iodine
Dexamethasone (incr/decr) ACTH levels
decreases
_________ is a medical glucocorticoid more potent than cortisol
dexamethasone
Excess cortisol can lead to what disease?
Cushing's
Gluconeogenesis is the formation of glucose from oxaloacetate via __________
phosphenol pyruvate
Triglycerides are formed by ________ synthesis from glucose
de novo
Glycolysis is the metabolism of __________ to pyruvate
glucose-6-phosphate
Glycogenolysis is stimulated by _________
cortisol
GLUT2 facilitates glucose uptake in the ______
liver
GLUT4 facilitates glucose uptake in the __________
muscles
After insulin binds to its receptors, _______ formation is stimulated
glycogen
When insulin binds to a cell receptor, __________ transporters move to the cell membrane
GLUT4
Entry of amino acids into the cell is facilitated when sinsulin binds to _________
its cell receptor
Lipogenesis is ________by insulin
stimulated
_______ is released together with its cleaved C peptide
insulin
Insulin is released in a _______ manner in response to a glucose infusion
BIPHASIC
What is secreated in response to the depolarization of beta cells and the opening of voltage-gated calcium channels?
Insulin
Vitamin D is a _________ hormone
steroid
Vitamin D is hydroxylated into its potent form in the _________
kidney
FSH goes to the ______ cells in males while LH goes to the ______ cells for negative feedback
Sertoli (anterior pituitary)
Leydig (anterior pituitary & hypothalamus)
Vitamin D is hydroxylated in what 2 organs of the body?
liver and kidney
Calcium may be taken up from the lumen of the gut by ______
endocytosis
All processes of calcium absorption require _________
calcium-binding proteins
Synthesis of calcium-binding proteins is stimulated by _______
