Endocrine System
Endocrine glands
1. secrete hormones directly into the bloodstream. 2. are the organs of the endocrine system. 3. help maintain homeostasis. 4. are ductless glands.
The hormones that comefrom the posterior pituitary
Are synthesized in the hypothalamus and are released from the posterior pituitary when nerve signals arrive.
Which of the following hormones is secreted by the anterior pituitary?
FSH
Which hormone induces its target cells to take up glucose, thereby lowering blood glucose levels?
Insulin
Which of the following is true regarding cortisol?
It promotes breakdown of fat and protein.
Which type of hormone requires a carrier protein in the blood?
Lipid-soluble hormone
Which hormone is secreted by the pineal gland?
Melatonin
What makes a cell responsive to a particular hormone?
The presence of a receptor for that particular hormone
The metabolic condition called ________ results from the destruction of the beta cells in the pancreas due to an autoimmune response.
Type 1 diabetes
The initial response to stress is called the ________ and is mediated mainly by ________.
alarm reaction; norepinephrine and epinephrine
Glucagon and insulin work ________ on blood glucose level
antagonistically
Thyroid hormone is somewhat unique in that it is a
biogenic amine that is lipid-soluble.
The major targets of growth hormone are ________.
bones and skeletal muscles
In most of its target cells, cortisol ________ glucose uptake and _______ protein metabolism.
decreases, increases
Once a structure is fully grown and mature, it will probably
down-regulate its receptors for growth hormone, as it no longer needs to continue to grow at a fast rate.
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.
intracellular signaling pathways within target cells are organized such that
each step allows for amplification of the signal where one molecule can activate many
Which of the following enters a target cell's nucleus and acts directly on the genes?
estrogen
Aldosterone ________.
functions to increase sodium reabsorption
The part of the brain that functions as a"master control center" of the endocrine system is the
hypothalamus
The hypothalamohypophysial portal system carries hormones from the
hypothalamus to the anterior pituitary
Damage to the liver might impair enzymatic degradation of some hormones.The levels of such hormones in the blood would therefore be expected to
increase
The pituitary gland is located _________ to the hypothalamus and is connected by the ________.
inferior ,infundibulum
Oxytocin results in more forceful smooth muscle contractions in the uterus by causing target cells to increase production of
inositol triphosphate
Which of the following is not a steroid hormone?
insulin
Lipophilic hormones bind to ___________ receptors of target cells.
intracellular
Cortisol binds to _________ receptors and has the effect of ________ blood glucose levels.
intracellular, raising
As someone starts to develop in puberty, most cells in their reproductive organs are probably starting to express
more receptors for sex hormones.
Which of these hormones is NOT secreted by the adrenal cortex?
norepinephrine
Which hormone is sometimes given to women to induce labor?
oxytocin
The hormone oxytocin is synthesized in the _____.
paraventricular nucleus
The hypothalamus
regulates the secretory activity of the pituitary gland
The rate of secretion of parathyroid hormone increases when
serum calcium levels decrease.
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
Generally, the shorter the half-life of a hormone
the more frequently it must be replaced.
The release of hormones from the adrenal medulla is stimulated by
the sympathetic division of the autonomic nervous system.
The ________ secretes several hormones that stimulate the development of lymphatic organs and regulates development and activity of T cells (white blood cells).
thymus
The ________ secretes a hormone that increases the body's metabolic rate, promotes alertness, quickens reflexes, and stimulates the fetal nervous system.
thyroid gland
A lack of dietary iodine can render the thyroid gland unable to synthesize TH. Without the negative feedback of TH, the anterior pituitary ____________, ultimately resulting in the development of a goiter.
will increase the release of TSH
