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203 Cards in this Set
- Front
- Back
Hormones that regulate:
Glucose and Lipids |
Insulin and Glucagon from Pancreas
Epinephrine from Adrenal Medulla |
|
Hormone that regulates:
Osmolarity and Volume |
Antidiuretic Hormone (ADH) from Posterior Pituitary
|
|
Hormone that regulates:
Sodium, Potassium, and Volume |
Aldosterone from Adrenal Cortex
|
|
Hormones that regulate:
Blood Pressure |
Aldosterone from Adrenal Cortex
Epinephrine from Adrenal Medulla |
|
Hormones that regulate:
Calcium and Phosphate |
Parathyroid Hormone (PTH) from Parathyroid Gland
1,25 dihydroxyvitamin D from Kidney |
|
Which endocrine glands produce protein/peptide hormones?
|
Hypothalamus, Pituitary Gland, Parathyroid Gland, Pancreas
|
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Mature peptide hormones are stored in _______.
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secretory vesicles
|
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Acute regulation occurs at the level of ________.
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Secretion (exocytosis)
|
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Long-term regulation occurs at the level of _________.
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Synthesis (gene expression)
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Which pituitary glands are dedicated glands?
|
Pituitary, Thyroid, Parathyroid, Adrenal, Pineal, Thymus glands
|
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True/False : Peptide hormones circulate in the blood bound to transport proteins.
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False; they usually circulate in the blood "free"
|
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What are the receptors that span the membrane called? (lol)
|
Transmembrane receptors :D
|
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Hormones induce what sort of rapid response?
|
Covalent modification (Phosphorylation)
|
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Hormones induce what sort of longer term responses?
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Transcription Factors (for gene expression)
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Where are peptide hormones degraded?
Where are they excreted? |
Degraded in the blood and in the liver
Excreted by the kidney |
|
What are catecholamine hormones?
|
Hormones produced by the adrenal gland, the "fight or flight" hormones.
|
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Are catecholamines produced in the medulla or the cortex of the adrenal gland?
|
Medulla. The medulla secretes mostly epinephrine but also norepinephrine.
|
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Catecholamines are made from which amino acid?
|
Tyrosine
|
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Catecholamines bind to what receptors and what kind of signal transduction pathway is used?
|
Adrenergic receptors, G-protein Coupled Receptors
|
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Where are steroid hormones produced?
|
Adrenal Glands, Ovaries, Testes
|
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What kind of molecule is a steroid hormone made from?
|
Cholesterol (a complex lipid!?)
|
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What are the five major classes of steroid hormones?
|
Progestins, Estrogens, Androgens, Glucocorticoids, Mineralocorticoids
|
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What kind of molecule is Vitamin D derived from?
|
Cholesterol with an open ring structure.
|
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Example of a Progestin and where it is synthesized
|
Progesterone, Ovary
Progestin is a class of steroid hormone |
|
Example of an Estrogen and where it is synthesized
|
Estradiol, Ovary
Estrogen is a class of steroid hormone |
|
Example of an Androgen hormone and where it is synthesized
|
Testosterone, DHT; Testes
Androgen is a class of steroid hormone |
|
Example of a Glucocorticoid and where it is synthesized
|
Cortisol; Adrenal Cortex
Glucocorticoid is a class of steroid hormone |
|
Example of a Mineralocorticoid and where it is synthesized
|
Aldosterone; Adrenal Cortex
|
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True/False : Steroid hormones circulate primarily bound to transport proteins
|
True; Steroid hormones are not particularly water soluble.
|
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Where are steroid hormone receptors primarily found?
|
The cytoplasm or the nucleus
|
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Steroids are stored as __________ in large _________ .
|
Cholesterol esters; lipid droplets
|
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Steroidogenic enzymes are localized in the ______________ and _________.
|
mitochondria; endoplasmic reticulum
|
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Regulation of steroid hormone production is at the level of ________ .
|
synthesis.
due to absence of secretory vesicles to store them in. |
|
True/False : Steroids can be further modified through peripheral conversion.
|
True.
Example: Androgen hormones can be converted to estrogens in the breast. |
|
How are steroid hormones metabolized?
|
By the liver, usually by making them more hydrophilic and then excreted by the kidney.
|
|
Where are iodothyronines made? (lol)
|
Thyroid gland :D
|
|
What amino acid are thyroid hormones derived from?
|
Tyrosine;
Two molecules of tyrosine are linked head-to-head |
|
What SPEHSHUL atom do iodothyronines have? (LOL)
|
IODINE LOL :D
|
|
What is the active form of thyroid hormone?
|
T3;
T4 can be deiodinated peripherally to form T3. |
|
True/False : Thyroid hormones circulate through the blood freely.
|
False;
Both T3 and T4 circulate tightly bound to transport proteins. |
|
How do iodothyronines act on the cell?
|
They act on nuclear receptors and are involved with regulating gene transcription.
|
|
What are the symptoms of hypoglycemia?
|
Autonomic - sweating, nausea
Neuroglycopenia - confusion, coma, death Hypoglycemia is low blood glucose (too much insulin) |
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What are the symptoms of hyperglycemia?
|
Osmotic stress - dehydration
Glucotoxicity - renal and retinal destruction, peripheral neuropathies, cardiovascular disease Type II Diabetes (all the above plus dyslipidemia and lipotoxicity) Hyperglycemia is high blood glucose |
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What is the difference between endocrine and exocrine glands?
|
Endocrine glands are ductless and release hormones directly into the extracellular space into capillaries and into the blood stream.
Exocrine glands have ducts and secrete products into body cavities or surfaces. |
|
What is the GLUT4 transporter and how is it regulated?
|
GLUT4 transporter is a transporter for the uptake of glucose into muscle and adipose cells. It is regulated by insulin and inserted into the membrane.
|
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Which part of the pancreas has a larger mass: the endocrine or exocrine?
|
Exocrine
|
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Where is the Islet of Langerhans?
|
Endocrine Pancreas; It is a cluster of endocrine cells within the exocrine pancreas (acinar cells).
|
|
Alpha cells in the pancreas produce which hormone?
|
Glucagon
|
|
Beta cells in the pancreas produce which hormone?
|
Insulin
|
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Is loss of insulin or loss of glucagon more dire for your health?
|
Insulin; glucagon's effects can also be induced by epinephrine.
|
|
Describe synthesis of insulin from proinsulin.
|
The insulin gene is transcribed into mRNA and translated into one contiguous protein, proinsulin. Proinsulin is packaged into membrane bound vesicles along with converting enzymes that cut the peptide into 3 chains (A, B, and C). Mature insulin, peptide A and B linked by two disulfide bonds, is secreted along with the biologically inactive C peptide.
|
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What kind of transporter is GLUT2?
|
High capacity transporter.
|
|
What is the first action of insulin?
|
To inhibit glucagon. Beta cells are located toward the middle and blood flow outwards gets the insulin to the insulin receptors on the alpha cells.
|
|
Which hormones elevate blood glucose?
|
Glucagon, Epinephrine, Growth Hormone, and Cortisol
(Only insulin decreases blood glucose.) |
|
The only organ that can export glucose is ___________ .
|
the liver.
... because it has glucose 6-phosphatase. |
|
Glucagon's quickest and most important action is _________ .
|
signalling the liver to export glucose.
|
|
How do hormonal levels change in concordance to blood glucose concentration?
|
<4.4mM (80mg/dL) insulin cessation
3.6mM-4.4mM (65mg/dL-80mg/dL) secretion of glucagon and epinephrine <3.6mM (or exercise or other stress) diffuse activation of sympathetic nervous system |
|
What is the structural difference between epinephrine and norepinephrine?
|
Epinephrine has a methyl group that norepinephrine doesn't.
|
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True/False : The adrenal glands receive more arteries than the kidney.
|
True. The kidney receives one artery while the adrenal glands receive more.
|
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What is produced in the adrenal cortex?
|
Aldoesterone, Cortisol, and androgens.
Three zones in the cortex produce three different hormones. |
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What is produced in the adrenal medulla?
|
Catecholamines
|
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What are the zones of the adrenal cortex called?
|
Zona Glomerulosa, Zona Fasciculata, Zona Reticularis
|
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What is produced in the Zona Glomerulosa of the adrenal cortex?
|
Mineralocorticoids
|
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What is produced in the Zona Fasciculata of the adrenal cortex?
|
Glucocorticoids
|
|
What is produced in the Zona Reticularis of the adrenal cortex?
|
Androgens
|
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How does norepinephrine become epinephrine?
|
Phenylethanolamine-N-methyl transferase induced by cortisol
|
|
Describe the synthesis of epinephrine.
|
L-Tyrosine -> L-DOPA -> Dopamine -> Norepinephrine -> Epinephrine
(Tyrosine hydroxylase *ratelimiting*, DOPA Decarboxylase, Dopamine beta Hydroxlase, Phenylethanolamine-N-methyl transferase) |
|
Epinephrine can only be made if there is ____________ around.
|
cortisol
|
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Why is the adrenal medulla dependent upon the adrenal cortex?
|
Adrenal cortex makes the cortisol. (When cortisol reaches the bloodstream, it's diluted and has no effect on other organs.)
|
|
How does the adrenal medulla detect low blood glucose levels?
|
Signal from the hypothalamus. The hypothalamus has an indirect plasma glucose receptor (low ATP/AMP level indicates low plasma glucose).
|
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True/False : There are no nerve connections between the anterior pituitary and the hypothalamus.
|
True.
|
|
What does the hormone arginine vasopressin do?
|
Arginine vasopressin = ADH lol
Increases water reabsorption by the collecting duct and causes peripheral vasoconstriction. Secreted when plasma sodium concentration is high. |
|
What does the hormone oxytocin do?
|
Required for milk ejection and causes uterine contraction.
|
|
What are the pars nervosa and the pars distalis?
|
Pars nervosa = Posterior pituitary
Pars distalis = Anterior pituitary |
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What hormones are secreted by the pars nervosa/posterior pituitary?
|
Vasopressin (ADH) and Oxytocin
|
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What hormones are secreted by the pars distalis/anterior pituitary?
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ACTH, TSH, LH, FSH, Growth Hormone, Prolactin
|
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How is secretion from the pars nervosa regulated?
|
Synaptic input
|
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How is secretion from the pars distalis regulated?
|
Hypothalamic hormones and feedback control
|
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What are the glycoprotein hormones?
|
TSH, LH, FSH
Thyroid Stimulating Hormone, Luteinizing Hormone, Follicle Stimulating Hormone |
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The _________ __________ gland serves as an interface between the brain and hormonal control of peripheral organs.
|
anterior pituitary
|
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The magnocellular hypothalamic neurons secrete ___________ and ________.
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vasopressin; oxytocin
|
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T4 is the ___hormone while T3 is the ______ hormone.
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pro; active
|
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What is a goiter?
|
Enlarged thyroid gland; does not refer to functional state
|
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True/False : T3 hormone makes ATP synthesis more efficient.
|
False; T3 hormone makes ATP synthesis less inefficient to increase heat production.
|
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True/False : If T4 enters a cell it is completely useless since it's the inactive form.
|
False. Deiodinase will show up and take off an iodine, thus turning the T4 molecule into a T3 molecule which is active. Yay.
|
|
What are the major functions of T3?
|
Attain and maintain a differentiated state and regulate growth
Regulate the efficiency of ATP use and production to maintain body temperature. |
|
How does the T3 receptor work?
|
T3 binds to a transcription factor which dimerizes with itself and attaches to the promotor region of T3 responsive genes.
|
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How is T3 regulated?
|
Firstly, T4 is the prohormone, so it's inactive until the deiodinase takes off an iodine from the outer ring which activates it. Then, there's an enzyme that takes the iodine off the inner ring rather than the outer ring, which is an inactive form of T3.
|
|
What is a cause of goiters?
|
Chronically elevated TSH levels
|
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In which kind of cell is thyroid hormone produced?
|
Epithelial cells (in the thyroid gland, duh.)
|
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Where is calcitonin made?
|
C cells in the thyroid gland.
|
|
Iodine is potentially toxic. Where is it stored?
|
Colloid spaces in the thyroid gland.
It is transported there via a Na/I symporter. |
|
What kind of receptor is the TSH receptor?
|
G-Protein Coupled Receptor with cAMP second messenger
|
|
What does TSH do?
|
Stimulates the secretion and synthesis of thyroid hormone.
|
|
What are thyroglobulin molecules?
|
Where tyrosine residues chill before they become thyroid hormones. TSH stimulates the degradation of thyroglobulin.
|
|
How does the plasma potassium concentration affect aldosterone levels?
|
Increased K stimulates aldosterone
Decreased K decreases aldosterone |
|
What does aldosterone do?
|
It increases sodium reabsorption and stimulates potassium excretion and hydrogen excretion in the distal tubule.
|
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True/False : Aldosterone is not dependent on ACTH.
|
True.
|
|
How is aldosterone synthesized? (the reactions, bwahahahaha)
|
Progesterone -> 11-Deoxycorticosterone -> Corticosterone -> Aldosterone
21 beta hydroxylase, 11 beta hydroxylase, aldosterone synthase |
|
What does cortisol do?
|
Stimulates gluconeogenesis, inhibits inflammatory response, suppresses the immune system, enhances vascular responsiveness to catecholamines
|
|
_________ has a pattern of diurnal secretion.
|
Cortisol
Highest in morning, lowest at night |
|
What are some side effects of glucocorticoids? (use of steroids)
|
Skin thinning and purpura, cataracts, hyperlipidemia, fluid retention, hyperglycemia (increased insulin resistance), hypertension, myopathy, osteoporosis
|
|
What are some effects of chronic glucocorticoid usage and hao2treat?
|
Decreased ACTH levels causing atrophy of adrenal cortex
Acute stress - hypotension Treatment - stress dose steroids, giving the amount the body usually makes when stressed |
|
Why is potassium homeostasis normal with glucocorticoid usage?
|
Renin Angiotensin system is intact. Yay.
|
|
Explain a low dose dexamethasone suppression test.
|
Dexamethasone given at night, feedbacks on hypothalamus and pituitary which decreases CRH and ACTH and thus decreasing cortisol release. Normal person has decreased cortisol in the morning. Cushings has increased cortisol.
|
|
What is Addison's Disease?
|
Lack or shortage of hormones produced in the adrenal gland.
|
|
What does 21 beta hydroxylase deficiency cause? (Adrenocortical hormones)
|
Decreased aldosterone
Decreased cortisol Increased androgens (secondary to increased ACTH) |
|
What does 17 beta hydroxylase deficiency cause? (Adrenocortical hormones)
|
Increased mineralocorticoids
Decreased cortisol Decreased androgens |
|
What does 11 beta hydroxylase deficiency cause? (Adrenocortical hormones)
|
Increased 11deoxycorticosterone
Decreased cortisol Increased androgens |
|
What does the alpha1 catecholamine receptor do?
|
Vasoconstriction
Effect of Epinephrine = Norepinephrine |
|
What does the beta1 catecholamine receptor do?
|
Heart - Increased heart rate and increased contractility
Effect of Epinephrine = Norepinephrine |
|
What does the beta2 catecholamine receptor do?
|
Vasodilation; Broncodilation (in lungs?)
Effect of Epinephrine >> Norepinephrine |
|
How does the high dose dexamethasone test work?
|
Pituitary adenomas (Cushing's Disease) suppresses cortisol after high dose.
|
|
Where is parathyroid hormone secreted? (lol)
|
Synthesized and secreted by the chief cells in the parathyroid gland. :D
|
|
What is the primary effect of parathyroid hormone?
|
Increase plasma levels of Ca++
|
|
How is calcium concentration sensed by the chief cells?
|
The calcium-sensing receptor in the chief cells is a G-protein coupled receptor which affects the gene expression of PTH.
CaSR activation by Ca++ inhibits PTH secretion and gene expression. |
|
What are the actions of parathyroid hormone?
|
Increase distal tubular reabsorption of calcium
Decrease proximal tubular resorption of Pi Increase activity of vitamin D 1alpha-hydroxylase Increases osteoclastic bone resorption Indirectly increases absorption of dietary calcium and Pi via effects on 1,25OH2D3 production |
|
Where does PTH act on the nephron?
|
Distal tubule for calcium
Proximal tubule for Pi |
|
Where is most of the body's calcium found?
|
In the skeleton as modified hydroxyapatite crystals embedded in bone matrix
|
|
What are osteoblasts?
|
Differentiated bone forming cells that secrete bone matrix upon which Ca++ and Pi mineral is deposited.
Bone forming cells |
|
What are osteocytes?
|
Mature bone cells derived from osteoblasts that are encased in lacunae within the mineralized bone matrix.
Involved in mechanotransduction, Pi metabolism |
|
What are osteoclasts?
|
Large multinucleated cells derived from hematopoietic precursors that are highly specialized to resorb bone
Break down old bone, mobilize Ca++ when needed by the body |
|
What is the osteoid?
|
Matrix that eventually becomes mature bone.
|
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Osteoclasts secrete __________ to ______ ______ old bone.
|
acid/protons; break down
|
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True/False : Osteoclasts don't have PTH receptors.
|
True. PTH acts on the osteoblast lineage which make cytochines and promote differentiation of osteoclasts.
|
|
What precursor to vitamin D is in our skin?
|
7-dehydrocholesterol
|
|
Light turns 7-dehydrocholesterol into what?
|
Cholecalciferol (vitamin D)
biologically inactive |
|
What is vitamin D2?
|
Provided by dietary sources and multivitamins, biologically inert, converted to active form in liver and kidneys
|
|
What is vitamin D3?
|
Naturally occuring form in humans, formed by ultraviolet light on precursors, biologically inert, converted to active form in liver and kidneys
|
|
What enzymes convert vitamin D to its active form?
|
25 hydroxylase in liver and 1alpha hydroxylase in kidney
1 a-hydroxylase is regulated by PTH and low Pi |
|
How is vitamin D inactivated?
|
Hydroxylation at the 24 position.
|
|
What are symptoms of vitamin D deficiency?
|
Rickets (bowed legs)
Osteomalacia (poorly mineralized bone) |
|
What action does vitamin D have on bones?
|
1,25 OH2 D3 acts on osteoblasts via a steroid hormone-like receptor to stimulate differentiation and function of osteoclasts.
Promote bone resorption. |
|
How does vitamin D promote intestinal calcium absorption?
|
Vitamin D acts via a nuclear receptor to increase gene transcription and translation. One gene product is calcium binding protein in the GI tract which facilitates calcium uptake (and also Pi uptake)
|
|
True/False : Vitamin D is fat soluble.
|
True.
Fat soluble vitamins - ADEK |
|
Where is calcitonin made?
|
Synthesized and secreted by the parafollicular or C cells of the parathyroid.
Stimulus for secretion is a rise in plasma calcium ion levels. |
|
What does calcitonin do?
|
Directly inhibits osteoclastic bone resorption and used clinically as anti-resorptive, but not required for maintenance of normocalcemia in humans.
|
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Reproductive systems are composed of three general parts:
_____________ _____________ _____________ |
Gonad (testes or ovary)
Reproductive tract External genitalia (plus placenta and breasts in female) |
|
True/False : Gonads have exocrine and endocrine function.
|
True.
Endocrine - production of hormones Exocrine - gametogenesis |
|
What is the difference between genetic sex, gonadal sex, and phenotypic sex?
|
Genetic - either XX or XY (or other)
Gonadal - presence of ovary or testes Phenotypic - internal and external genitalia |
|
What is the SRY gene?
|
Sex-determining region of the Y chromosome
SRY induces testicular differentiation SRY inhibits ovarian differentiation |
|
In the absence of a Y chromosome, _________ forms.
|
an ovary! ;D
|
|
What are the mesonephric and mullerian ducts?
|
Undifferentiated potential reproductive tracts.
Mesonephric -> male duct Mullerian -> female duct One dies. |
|
The testis forms at __ weeks and secretes the two hormones ________ and _________ .
|
7; testosterone; antimullerian hormone
testosterone promotes development of mesonephric duct, forms a penis and induces descent of testes into scrotum antimullerian hormone causes degeneration fo mullerian duct |
|
True/False : The "default" gender is female.
|
True.
If no Y chromosome lack of testosterone and antimullerian hormone causes default into female. |
|
What are the gonad, the tract, and the accessory glands in males?
|
Gonad - testes in the scrotum
Tract - tubular structures from testis to tip of penis, continuous with seminiferous tubules of testis, includes urinary system, involved in unidirectional transport of gametes Accessory glands - prostate, produces semen |
|
What are the gonad, the tract, and accessory glands in females?
|
Gonad - ovary
Tract - Tubular structures from ovary to opening of vagina, discontinuous from gonad, does not include urinary system, involved in bidirectional transport of male and female gametes Accessory glands - none associated with tract, but maybe boobs or something |
|
What kind of hormones do the gonads produce?
|
steroid hormones and protein hormones
|
|
Describe generally the process of meiosis for gametes.
|
spermatogonia -> primary spermatocyte -> secondary spermatocyte -> spermatid
oogonia -> primary oocyte -> secondary oocyte -> egg [Enter meiosis, first meiotic division, second meiotic division] |
|
Gametogenesis in the testis occurs in the ___________ __________.
|
seminiferous tubules
which actually are one continuous tube that is continuous with the male tract |
|
Sperm complete meiosis within the ______.
|
testis
|
|
What is spermiogenesis?
|
The transformation of sperm where they develop a tail and other structures necessary for fertilization.
|
|
True/False : Sperm are released from the testis as immature and immotile.
|
True. They mature and become motile in part of the male tract (epididymis)
|
|
Gametogenesis in the ovary occurs in ______________ .
|
follicles!
|
|
In the ovary, what are cumulus cells?
|
Somatic cells surrounding the egg.
|
|
Eggs are secondary oocytes arrested in which phase of meiosis?
|
metaphase of the second meiotic division.
|
|
What is GnRH (gonadotropin releasing hormone)?
|
It's a hormone produced by the hypothalamus which stimulates the gonadotropes of the pituitary gland to secrete the gonadotropins FSH and LH.
|
|
What do LH and FSH do in males?
|
Stimulate the production of testosterone and spermatogenesis
|
|
What do LH and FSH do in females?
|
LH and FSH induce the production of estrogen from the ovary for the first half of the menstrual cycle.
|
|
Estrogen initially exerts a _______ feedback on the hypothalamus and pituitary, but at midcycle, it switches to __________ feedback causing a gonadotropin surge which induces ovulation.
|
negative; positive
|
|
After ovulation, the ovary produces __________ (and estrogen) during the second half of the cycle.
|
progesterone
|
|
How is puberty activated?
|
Before puberty, the CNS inhibits the hypothalamus from producing GnRH, but the inhibition is removed and the gonadal axis is activated.
|
|
What is a difference between the roles of the somatic cells around the gametes in males and females?
|
The male somatic nurse cells are not released with the sperm, but the female somatic cumulus cells are released with the egg.
|
|
Which organ releases LH and FSH?
|
The pituitary gland
|
|
What does the hypothalamus gland release (for the reproductive system)?
|
GnRH
|
|
Describe the organization of testis.
|
The testis is divided into several hundred lobules (lobuli testis).
Each lobule is divided into 2-4 coils of seminiferous tubules. Each tubule is lined by seminiferous epithelium. |
|
What types of cells are in the seminiferous epithelium?
|
Developing sperm cells and nurse cells (Sertoli)
|
|
Spermatozoa which are ready to be flushed out have what distinctive shape?
|
streamlined nuclei
|
|
What is the function of the Sertoli cells?
|
They are the nurse cells for sperm. They surround developing sperm cells and phagocytize dead sperm cells and residual bodies.
They also secrete androgen-binding protein into the lumens of the seminiferous tubules, which concentrates testosterone in the seminiferous tubules. They also produce fluid that washes the released spermatozoa from the testis to the epididymis. |
|
What is a residual body (sperm)?
|
The cytoplasm and stuff left behind in the creation of a sperm.
|
|
What is the blood-testis barrier?
|
tight junctions that Sertoli cells form which protect the sperm cells from immune attack (because they don't have exactly the same DNA) and chemicals
Barrier exists between spermatogonia and primary spermatocytes |
|
What is the acrosome?
|
It's a membrane lined bag of enzymes at the front of the head of the sperm. It's necessary to penetrate the layer that encloses the egg.
It is coated with secretions from the epididymis to prevent premature release of enzymes. |
|
What is decapacitation and capacitation of sperm?
|
Decapacitation - head of sperm is coated with secretions from the epididymis to prevent acrosome being released
Capacitation - this protective layer is removed in the oviduct of the female tract |
|
What is the Leydig cell and what does it do?
|
Leydig cells live in the peritubular compartment in between the seminiferous tubules and produces testosterone in response to stimulation by LH.
|
|
True/False : Sperm cells respond to testosterone and FSH.
|
False. Sperm cells don't directly respond to testosterone or FSH, but these actions are mediated by the Sertoli cells.
|
|
How is testosterone converted to Dihydrotestosterone?
|
5 alpha reductase converts testosterone to DHT
|
|
If testosterone goes to the adipose or liver tissue, what is it converted to?
|
Testosterone is converted to estradiol by aromatase
|
|
What kind of receptor is the androgen receptor?
|
a transcription factor
|
|
What can secreted testosterone be peripherally converted to?
|
DHT and Estradiol
|
|
Testosterone, DHT, and Estradiol circulate in the blood bound to a transport protein, _______________ .
|
sex hormone binding protein (lol)
|
|
Give a tour for the travelling sperm.
|
rete testis -> efferent ductules -> epididymis -> vas deferens -> ejaculatory duct -> male urethra (prostatic, membranous, penile)
|
|
What stuff is in semen?
|
Fructose, Zinc, and Citrate
|
|
The penis is composed of ___ erectile bodies. What are they called?
|
three;
2 corpora cavernosa 1 corpus spongiosum (with urethra) |
|
What are the arteries that flow into the erectile tissue called?
|
helicine arteries
|
|
What are special characteristics of helicine arteries?
|
They have thick walls that can contract and they control the blood flow. During erotic parasympathetic stimulation, the helicine arteries relax and blood flow increases, causing erection.
|
|
Parasympathetic cavernous nerves release which signalling molecule?
|
NO (nitric oxide)
|
|
Termination of erection is called __________ .
|
detumescence
|
|
How does androgen abuse lead to infertility?
|
Large amounts of androgens suppresses hypothalamus and pituitary gland function.
|
|
Sertoli cells respond to which hormones?
|
FSH and testosterone
|
|
Leydig cells respond to which hormone?
|
LH
|
|
What is the corpus luteum?
|
forms from a follicle after ovulation of an egg.
|
|
True/False : There are many tubules in the ovary.
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False; There are no tubules in the ovary. Just a lot of follicles.
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True/False : Follicular phase is variable
Luteal phase is always 14 days. |
True.
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Primary oocytes are arrested at which stage of meiosis?
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First meiotic prophase
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What are granulosa cells?
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Enlarged follicle cells
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What is the zona pellucida?
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An acellular matrix secreted by the oocyte.
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Thecal cells respond to which hormone?
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LH; thecal cells are comparable to male lyedic cells
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Splitting of the granulosa layer and formation of a fluid filled antrum marks the development of an _____ ________ ________.
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early antral follicle
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Endocrine function doesn't occur until the follicle is a ______ _______ __________.
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large antral follicle
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What does the thecal cell produce in response to LH?
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produces androstenedione from cholesterol
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Androstenedione turns into ___________ or ___________ .
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testosterone or estradiol
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FSH promotes androstenedione to _____________ .
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estradiol
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What happens during the follicular phase?
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Antral follicles produce estradiol and granulosa cells produce inhibin. This inhibits FSH and follicles that are dependent on FSH die. Selection of the dominant follicle. Then the dominant follicle secretes high levels of estrogen
Estrogen levels become high and positive feedback begins which results in ovulation |