Exam 1 Ch:17,18,19,20,21,22 Flashcards
(250 cards)
Endocrine glands
are ductless glands.
are the organs of the endocrine system.
secrete hormones directly into the bloodstream.
help maintain homeostasis.
All of the choices are correct.
All of the choices are correct.
Which is not characteristic of the endocrine system?
Effects: causes metabolic activity changes in target cells
Response time: slow reaction time = seconds to hours
Duration of response: long-lasting = minutes to weeks
Recovery time: rapid, immediate return to prestimulation level
Communication method: hormones in the bloodstream
Recovery time: rapid, immediate return to prestimulation level
Aldosterone release can be triggered by the presence of the blood-borne messenger angiotensin II or by low levels of sodium, and so its secretion regulation is said to be
purely neural.
both hormonal and humoral.
both antagonistic and synergistic.
both neural and synergistic.
purely hormonal.
both hormonal and humoral.
Follicle-stimulating hormone is a
glycoprotein.
steroid.
monoamine.
oligopeptide.
glycoprotein
Protein hormones are
lipid-soluble.
water-soluble.
soluble in both water and lipids.
soluble in neither water nor lipids.
water-soluble.
When a chemical messenger helps initiate an inflammatory response by causing cellular changes in neighboring cells, it is demonstrating ___________ signaling.
autocrine
paracrine
allomone
pheromone
paracrine
Most hormones are made of chains of amino acids and are therefore
steroids.
biogenic amines.
proteins.
catecholamines.
proteins
Which type of hormone requires a carrier protein in the blood?
Autocrine hormone
Water-soluble hormone
Oligopeptide
Lipid-soluble hormone
Lipid-soluble hormone
The binding of a hormone and a carrier protein is _______; a very ______ fraction of such a hormone in the blood is bound to a carrier at any one point in time.
temporary; large
temporary; small
permanent; large
permanent; small
temporary; large
Generally, the shorter the half-life of a hormone
the more frequently it must be replaced.
the less frequently it must be replaced.
the more frequently it must be replaced.
The half-life of a hormone is
one-half of the time it takes to synthesize the chemical messenger molecule.
the time necessary to reduce the hormone concentration in the blood to half of what had been secreted.
half the time until the hormone molecule dissolves.
half of the duration of the hormone’s effects on its target cells throughout the body.
the time necessary to reduce the hormone concentration in the blood to half of what had been secreted.
When the effects of water-soluble hormones on their target cells are considered, the hormone itself is
the G protein.
the second messenger.
the first messenger.
the hormone-response element.
the phospholipase.
the first messenger.
Within the adenylate cyclase signal transduction pathways of target cells, cAMP activates
the G protein.
adenylate cyclase.
protein kinase.
the receptor.
transcription of a mRNA.
protein kinase.
In the signal transduction pathway that results in the formation of inositol triphosphate, the G protein directly activates
phospholipase C.
protein kinase A.
calmodulin.
adenylate cyclase.
phospholipase C.
Intracellular signaling pathways within target cells are organized such that
each step allows for amplification of the signal where one molecule can activate many.
each step involves one molecule activating or synthesizing exactly one other molecule for precise control.
enzymes are used up and degraded after each individual reaction they catalyze.
each step allows for amplification of the signal where one molecule can activate many.
Reduced hormone concentration in the blood often causes target cells to
up-regulate receptors in order to increase cell sensitivity.
up-regulate receptors in order to decrease cell sensitivity.
down-regulate receptors in order to increase cell sensitivity.
down-regulate receptors in order to decrease cell sensitivity.
up-regulate receptors in order to increase cell sensitivity.
As someone starts to develop in puberty, most cells in their reproductive organs are probably starting to express
more receptors for sex hormones.
fewer receptors for sex hormones.
more receptors for sex hormones.
Once a structure is fully grown and mature, it will probably
up-regulate its receptors for growth hormone, as it no longer receives as much of the ligand.
up-regulate its receptors for growth hormone, as it no longer needs to continue to grow at a fast rate.
down-regulate its receptors for growth hormone, as it no longer receives as much of the ligand.
down-regulate its receptors for growth hormone, as it no longer needs to continue to grow at a fast rate.
down-regulate its receptors for growth hormone, as it no longer needs to continue to grow at a fast rate.
The part of the brain that functions as a “master control center” of the endocrine system is the
pineal gland.
cerebral cortex.
spinal cord.
hypothalamus.
adrenal cortex.
hypothalamus.
The pituitary gland is located _________ to the hypothalamus and is connected by the ________.
superior, thalamus
inferior, infundibulum
inferior, epithalamus
posterior, infundibulum
inferior, infundibulum
Which lobe of the pituitary is larger and secretes more hormones?
Anterior pituitary
Posterior pituitary
Anterior pituitary
The hormones that come from the posterior pituitary
are synthesized there and are released upon signals from the anterior pituitary.
are synthesized in the hypothalamus and are released from the posterior pituitary when nerve signals arrive.
are synthesized in the anterior pituitary and are transported to and from the posterior pituitary by the primary and secondary plexus.
are synthesized in the posterior pituitary and released by the anterior pituitary by way of the hypophyseal portal system.
are synthesized in the hypothalamus and are released from the posterior pituitary when nerve signals arrive.
The two hormones released from the posterior pituitary are
oxytocin and antidiuretic hormone.
thyrotropin-releasing hormone and corticotropin-releasing hormone.
prolactin and growth hormone.
prolactin and vasopressin.
follicle-stimulating hormone and leutenizing hormone.
oxytocin and antidiuretic hormone.
In which order would blood flow through these structures as it travels from the hypothalamus to the pituitary gland?
a: Primary plexus
b: Secondary plexus
c: Hypophyseal portal veins
a - b - c
a - c - b
c - a - b
b - a - c
c - b - a
a - c - b