Pregunta 1
Pregunta
Which of the following hormones derive from amino acids?
Respuesta
-
estradiol
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epinephrine
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thyroid hormones
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calcitriol
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dopamine
Pregunta 2
Pregunta
Which of the following statements about hyperthyroidism are TRUE?
Pregunta 3
Pregunta
List at least three groups of plasma membrane receptors
1) [blank_start]Ion[blank_end] channels
2) [blank_start]G[blank_end]-[blank_start]Protein[blank_end] coupled receptor
3) [blank_start]Death[blank_end] receptors
Pregunta 4
Pregunta
G protein-coupled receptors
Respuesta
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are associated with monomeric G-proteins
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are receptors for lipophilic hormones
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transmit the signal of epinephrine and glucagon
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have an intracellular domain rich in tyrosine
Pregunta 5
Pregunta
Which of the following statements are NOT TRUE?
Respuesta
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glucocorticoids are synthesized in zona glomerulosa of the adrenal gland
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adrenal androgens are DHEA and 5-dihydrotestosterone
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5-dihydrotestosterone is more potent androgen than testosterone
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renin stimulates the conversion of angiotensin 1 into angiotensin 2
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17-hydroxylase is the principle regulatory enzyme in streroidogenesis
Pregunta 6
Pregunta
List at least 3 second messengers in the process of signal transduction
1) cyclic [blank_start]AMP[blank_end]
2) cyclic [blank_start]GMP[blank_end]
3) [blank_start]calcium[blank_end]
Pregunta 7
Pregunta
Which of the following statements about hypothyroidism are TRUE:
Pregunta 8
Pregunta
Which of the following statements are NOT TRUE?
Respuesta
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CYP 450 side chain cleavage enzyme is the key regulatory enzyme in the synthesis of all the steroid hormones
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25-dehydrogenase is the main regulatory enzyme in the synthesis of calcitriol
-
calcitriol causes a decrease of blood Ca2+ levels
-
cortisol has a prominent hyperglycemic effect
Pregunta 9
Pregunta
Which of the following statements are TRUE:
Respuesta
-
testosterone is less potent androgen than 5-dihydrotestosterone
-
glucocorticoids are synthesized in zona fasciculata of the adrenal gland
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angiotensin ll stimulates the production of aldosterone in zona glomerulosa of the adrenal gland
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testosterone is converted into estradiol by 17-ketoreduetase (17β- dehydrogenase)
Pregunta 10
Pregunta
Based on their chemical composition hormones are:
Pregunta 11
Pregunta
Which of the following statements are TRUE:
Respuesta
-
phosphodiesterase is inhibited by insulin
-
epinerphrine and ACTH use cAMP as a second messenger
-
insulin uses PI3K signaling pathway
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guanylyl cyclase activates protein kinase C (PKC)
Pregunta 12
Pregunta
Which of the following hormones are secreted by anterior pituitary gland:
Pregunta 13
Pregunta
Which of the following enzymes are involved in the biosynthesis of corticosteroids the adrenal cortex:
Pregunta 14
Pregunta
Which of the following is NOT TRUE:
Respuesta
-
Cholesterol side chain cleavage by P450 scc results in production of pregnolone
-
Cortisol is produced in zone fasciculata
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Aldosterone is produced in zona reticularis
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Estrogens biosynthesis requires aromatase activity
Pregunta 15
Pregunta
Which of the following is NOT TRUE:
Respuesta
-
Thyroid hormones are made from tyrosine
-
The synthesis of thyroid hormones is stimulated by TSH
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T4 is more active than T3
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Iodine transport in the thyroid follicle is energy dependent
Pregunta 16
Pregunta
What happens to protein kinase A (PKA) following the binding of cAMP
Respuesta
-
the regulatory subunits of PKA dissociate, therby activating the catalytic subunits
-
PKA catalytic subunits bind to the regulatory subunits
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the regulatory subunits dissociate from the catalytic subunits causing inactivation of the enzyme
Pregunta 17
Pregunta
Which of the following is NOT TRUE:
Respuesta
-
Thyroid hormones T3 and T4 derive from threonine
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TSH and ACTH bind to cell surface G-proteins coupled receptors (GPCR)
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Insulin is a polypeptide hormone that consists of A and B chain
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ACTH and endorphins derive from a large precursor called POMC
Pregunta 18
Pregunta
Which of the following about testosterone is NOT TRUE:
Respuesta
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Testosterone is a lipophilic hormone
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Testosterone has cell surface receptors with tyrosine kinase activity
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Testosterone is formed from dihydrotestosterone (DHT) in peripheral tissues
-
DHT is formed from testosterone in reaction catalyzed by 5-α-reductase
Pregunta 19
Pregunta
Ras protein is a key regulator in cell proliferation and its activity is enhanced by activated tyrosine kinase. Its action include:
Pregunta 20
Pregunta
Which of the following is TRUE:
Respuesta
-
Adrenaline and Glucagon inhibit glycogen phosphorylase
-
Cortisol stimulates gluconeogenesis and lipolysis
-
Aldosterone increases blood pressure
-
The major driving force for aldosterone biosynthesis is angiotensin II
Pregunta 21
Pregunta
Which of the following is TRUE:
Respuesta
-
The active form of vit. D3 is calcitriol
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Vit. D3 is synthesized in the skin from 7- dehydrocholesterol under UV-light
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Calcitriol inhibits the intestinal absorption of Ca2+ and phosphate
-
Calcitriol plays important role in bone mineralization
Pregunta 22
Pregunta
Which of the following hormones are secreted by the anterior lobe of the pituitary gland?
Respuesta
-
FSH
-
Prolactin
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Renin
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ADH
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Oxytocin
-
TRH
Pregunta 23
Respuesta
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can signal through MAPK pathway
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triggers cAMP- dependent pathway
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can signal through P13K-pathway
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has dimeric receptors with intrinsic tyrosine kinase activity
Pregunta 24
Pregunta
Which are the mediators of the signal of lipophilic hormones?
Pregunta 25
Pregunta
Which of the following statements about thyroid hormones are TRUE?
Respuesta
-
T4 can be a product both of the thyroid and the peripheral tissues
-
T3 can be a product both of the thyroid and the peripheral tissues
-
T3 is more active than T4
-
Thyroid receptors are cytosolic intracellular
Pregunta 26
Pregunta
Which of the following statements about aldosterone are TRUE?
Respuesta
-
its synthesis is stimulated by ACTH
-
its synthesis is stimulated by angiotensin ll
-
it decreases K+ and H+ excretion
-
it increases Na+ and water reabsotption
-
its receptors are cytosolic intracellular
-
it is synthesized in zona fasciculata of the adrenal cortex
Pregunta 27
Pregunta
Which of the following hormones are stored and released by the posterior lobe of the pituitary gland?
Respuesta
-
FSH
-
Prolactin
-
ACTH
-
ADH (vasopressin)
-
Oxytocin
Pregunta 28
Pregunta
Which of the following statements are TRUE:
Respuesta
-
divergention of the signal means that different signal pathways have the same common targets or intermediate components
-
crosstalk of the signals means that one signal molecule can transmit signals from different extracellular messengers (signal molecules)
-
acetylcholine transmit its signals through receptors associated with ion channels
-
acetylcholine transmit its signals through receptors associated with intrinsic serine-threonine kinase activity
Pregunta 29
Pregunta
Which of the following hormones have cell-surface receptors?
Respuesta
-
epinerphrine
-
testosterone
-
calcitriol
-
insulin
-
dopamine
-
retinols
Pregunta 30
Pregunta
Based on their mechanism of action the hormones are:
Respuesta
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Autocrine
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Peptide
-
Steroid
-
Paracrine
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Endocrine
Pregunta 31
Pregunta
Which of the following hormones bind to intracellular receptors:
Respuesta
-
Thyroid hormones
-
TSH
-
Glucagon
-
ACTH
-
Steroid hormones
Pregunta 32
Pregunta
Which of the following hormones have cell surface receptors:
Respuesta
-
Glucagon
-
Testosterone
-
Insulin
-
T4 and T3
-
Growth hormone
Pregunta 33
Pregunta
Which of the following statements about insulin receptor is TRUE
Respuesta
-
it has intrinsic tyrosine kinase activity
-
it is located in the nucleus
-
it is a dimer composed of two α and two β subunits
-
it is coupled with G-protein
Pregunta 34
Pregunta
Which of the following is TRUE:
Respuesta
-
C.AMP is a key second messenger in the transduction of hormone signals
-
Adenylyl cyclase is activated by insulin
-
Adenylyl cyclase catalyzes the synthesis of AMP from ATP
-
Hormones like adrenaline, glucagon and ACTH use cGMP as second messenger
Pregunta 35
Pregunta
Which of the following is TRUE:
Respuesta
-
Insulin receptor has serine/threonine kinase activity
-
Binding of insulin to its membrane receptor stimulates the tyrosine kinase activity of the β-subunits
-
Insulin is a lipophilic hormone
-
Cortisol is a lipophilic hormone
Pregunta 36
Pregunta
Which of the following is NOT TRUE:
Respuesta
-
Cholesterol side chain cleavage by P450 scc results in production pregnenolone
-
Cortisol is produced in zona glomerulosa
-
Aldosterone is produced in zona reticularis
-
Testosterone biosynthesis requires aromatase activity
Pregunta 37
Pregunta
Which of the following are second messengers:
Pregunta 38
Pregunta
Which of the following hormones stimulate adenylyl cyclase:
Respuesta
-
Insulin
-
ACTH
-
Growth hormone
-
Testosterone
-
Glucagon
Pregunta 39
Pregunta
Which of the following hormones are cholesterol derivatives:
Respuesta
-
Calcitriol
-
Cortisol
-
T3 and T4
-
Estradiol
-
ACTH