Endocrine Practice Test
Which does NOT apply to hormones? They are secreted into the blood by ductless glands. All hormones are derived from cholesterol. They are chemical regulators that are conveyed from one organ to another via the bloodstream. In some cases, the same chemical substances can also function as local regulators and/or neurotransmitters. They are sometimes secreted by neural tissue.
All hormones are derived from cholesterol.
Steroid hormone receptors may be found
Both in the cytoplasm and in the nucleus.
Endocrine glands secrete their products into ducts.
False
Which is an accurate description of the posterior pituitary and its functions?
It is neural tissue, and vesicles containing oxytocin and vasopressin are transported to axon terminals there.
Which type of hormone requires a carrier protein in the blood?
Lipid-soluble hormone
What is a main difference between the modes of action of peptide hormones and steroid hormones?
Peptide hormones bind to receptors on the cell surface, whereas steroid hormones bind to intracellular receptors.
What term describes hormones that influence the secretion of other hormones?
Tropic
Most lipid-soluble hormones are derived from cholesterol.
True
Which region of the adrenal cortex synthesizes glucocorticoids?
Zona fasciculata
Carrier proteins would be required by ____________ when transported in the blood.
aldosterone
Glucagon and insulin work ________ on blood glucose levels.
antagonistically
The hormones that come from the posterior pituitary
are synthesized in the hypothalamus and are released from the posterior pituitary when nerve signals arrive.
A nonsteroid hormone acts on a target cell by
causing synthesis of a second messenger
Steroid hormones are lipids, derived from
cholesterol
If the adrenal glands were removed from a patient, his plasma cortisol levels would ________, secretion of CRH by the ________ would ________, and secretion of ACTH by the ________ would ________.
decrease; hypothalamus; increase; adenohypophysis; increase
In response to excessive amounts of hormone, a target cell may reduce its number of receptors for that hormone. This is an example of
down-regulation
When it becomes necessary to enlist the fight-or-flight response, a hormone that is released during the alarm phase of the general adaptation syndrome is ________.
epinephrine
Polypeptide and glycoprotein hormones can be taken orally.
false
Regulating hormones from the hypothalamus ________.
first enter into the hypophyseal portal system
The hormone that increases the rate of glycogen breakdown and glucose release by the liver is
glucagon
Several hormones are synthesized in the hypothalamus and transported to the anterior pituitary gland. The mechanism of transportation from hypothalamus to anterior pituitary gland is through the ________.
hypophyseal portal system
The part of the brain that functions as a "master control center" of the endocrine system is the
hypothalamus
Where is oxytocin produced?
hypothalamus
You have discovered a novel steroid hormone. You'd like to isolate its receptor as part of your next project. Where should you look first?
in the cytoplasm
The pituitary gland is located ________ to the hypothalamus and is connected by the ________.
inferior; infundibulum
The hypothalamic-hypophyseal tract ________.
is partly contained within the infundibulum
Compared to the nervous system, the endocrine system
may have a longer lasting effect
A hormone is a ______ and the target cell is __________.
molecule that has a metabolic effect on another cell; a cell that has receptors for specific hormones
Compared to the nervous system, the endocrine system has
more widespread and long-lasting effects.
In response to high blood glucose, the pancreas releases insulin to enable glucose to enter body cells. When the blood glucose level returns to normal, insulin release stops. This is an example of regulation by
negative feedback
In the signal transduction pathway that results in the formation of inositol triphosphate, the G protein directly activates
phospholipase C
Cellular responses to hormones that initiate second-messenger systems include ________.
possible activation of several different second-messenger systems
Within the adenylate cyclase signal transduction pathways of target cells, cAMP activates
protein kinase
cAMP activates ______ that activates other enzymes in the cell.
protein kinase
Thyroid hormones bind to receptors which
regulate gene transcription.
Exocrine glands differ from endocrine glands in that exocrine glands
secrete through ducts or tubes to the body's exterior.
ACTH ________.
secretion is regulated by a hypothalamic regulatory hormone
What is the function of antidiuretic hormone (ADH)?
stimulates retention of water by the kidneys
When the effects of water-soluble hormones on their target cells are considered, the hormone itself is
the first messenger.
What makes a cell responsive to a particular hormone?
the presence of a receptor for that particular hormone
Adenohypophyseal function is regulated by the hypothalamus.
true
The metabolic condition called ________ results from the destruction of the beta cells in the pancreas due to an autoimmune response.
type 1 diabetes