Ch. 16 A&P
Chemical substances secreted by cells into the extracellular fluids and that regulate the metabolic function of other cells in the body are called ________.
Hormones
Direct gene activation involves a second-messenger system.
False
All peptide hormone synthesis requires gene activation that produces mRNA.
T
Which of the following is not a change that may be caused by hormonal stimulus?
a change in membrane potential
direct control of the nervous system
the stimulation of a genetic event resulting in protein synthesis
an increase in enzymatic activity
direct control of the nervous system
The ability of a specific tissue or organ to respond to the presence of a hormone is dependent on ________.
the presence of the appropriate receptors on the cells of the target tissue or organ
Thyroid hormone (a small iodinated amine) enters target cells in a manner similar to ________.
steroid hormones, because both diffuse easily into target cells
What ion is sometimes used as a second messenger of amino acid–based hormones?
Calcium
Both "turn on" factors (hormonal, humoral, and neural stimuli) and "turn off" factors (feedback inhibition and others) may be modulated by the activity of the nervous system.
T
Virtually all of the protein or amino acid-based hormones exert their effects through intracellular ________.
Second messengers
Which of the following is not a type of hormone interaction?
synergism
feedback
antagonism
permissiveness
feedback
Which of the following is not a change typically produced by a hormonal stimulus?
induces secretory activity
stimulates production of an action potential
activates or deactivates enzymes
alters plasma membrane permeability
stimulates production of an action potential
The second-messenger mechanism of hormone action operates by ________.
binding to specific receptors and employing the services of G proteins and cAMP
Cells that respond to peptide hormones usually do so through a sequence of biochemical reactions involving receptor and kinase activation. In order for cells to respond, it is necessary for first and second messengers to communicate. This is possible because ________.
G protein acts as the link between first and second messengers
Cellular responses to hormones that initiate second-messenger systems include ________.
possible activation of several different second-messenger systems
In circumstances where the body requires prolonged or increased levels of a hormone, the DNA of target cells will specify the synthesis of more receptors on the surface of the cells of the target organ. This is known as ________.
up-regulation
ACTH stimulates the adrenal cortex to release corticosteroid hormones.
T
LH is also referred to as a gonadotropin.
t
Oxytocin is a strong stimulant of uterine contractions.
T
The hypothalamic-hypophyseal tract ________.
is partly contained within the infundibulum
Oxytocin ________.
release is an example of a positive feedback control mechanism
What role do the kidneys play in erythropoiesis?
The kidneys detect low levels of oxygen in the blood.
What triggers erythropoietin (EPO) production to make new red blood cells?
reduced availability of oxygen
What organ in the body regulates erythrocyte production?
kidney
Peptides called NPY and AgRP are powerful appetite enhancers.
T
Ghrelin, produced by the stomach, is a powerful appetite stimulant.
T
Many factors influence BMR. What is the most critical factor?
the ratio of surface area to volume (weight) of the body
The amount of ________ produced is probably the most important hormonal factor in determining BMR.
thyroxine
When blood glucose levels are low, the body begins to use more noncarbohydrate fuels for energy production. This process is called glucose activation.
F
The preferred energy fuel for the brain is fat.
F
The increased use of noncarbohydrate molecules for energy to conserve glucose is called glucose sparing.
t
Glucose can be obtained from ________.
glycogenolysis
Which of the choices below is not a source of glucose during the postabsorptive state?
absorption of glucose from the GI tract
lipolysis in adipose tissues and the liver
glycogenolysis in the liver
catabolism of cellular protein
absorption of glucose from the GI tract
Which hormone directs essentially all the events of the absorptive state?
insulin
Which of the choices below happens during the absorptive state?
Anabolic processes exceed catabolic ones.
Where are oxytocin and antidiuretic hormone (ADH) made? Select from letters A-D.
A
Which of the following is not a category of endocrine gland stimulus?
enzyme
Which of the choices below is not a factor required for target cell activation by hormone receptor interaction?
type of hormone
Which of the following is not a steroid-based hormone?
epinephrine
Eicosanoids do not include ________.
hydrocortisones
Thyroxine is a peptide hormone, but its mechanism is different from other peptide hormones. Which of the following statements is true concerning this difference?
It does not require a second messenger to effect a response.
Steroid hormones exert their action by ________.
entering the nucleus of a cell and initiating or altering the expression of a gene
Hormones often cause a cell to elicit multiple responses; this is because ________.
during protein kinase activation, enzymes phosphorylate many other enzymes
One of the least complicated of the endocrine control systems directly responds to changing blood levels of ions and nutrients. Which of the following describes this mechanism?
humoral stimulation
ADH ________.
is inhibited by alcohol
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 neurohypophysis or posterior lobe of the pituitary gland is not a true endocrine gland because ________.
it is only a hormone storage area that receives hormones from the hypothalamus for release
The major targets of growth hormone are ________.
bones and skeletal muscles
Regulating hormones from the hypothalamus ________.
first enter into the hypophyseal portal system
Why does antidiuretic hormone help regulate an abnormal increase in solute concentration in the extracellular fluid?
It causes reabsorption of water by the kidney, resulting in increased blood water volume and a decreased solute concentration.
Oxytocin and ADH are produced in the posterior pituitary.
f
Growth hormone solely exerts its influence by targeting other endocrine glands to produce hormones.
f
ACTH ________.
secretion is regulated by a hypothalamic regulatory hormone
A man has been told that he is not synthesizing enough follicle-stimulating hormone (FSH), and for this reason he may be unable to father a child. Choose the correct statement to explain this problem.
FSH stimulates sperm production in the testes.
Iodine is an essential element required for the synthesis of thyroxine.
t
The endocrine gland that is probably malfunctioning if a person has a high metabolic rate is the parathyroid.
f
Thyroid hormone production requires the presence of iodine and calcium.
f
Which of the following is not a parathyroid gland mechanism to maintain adequate levels of blood calcium?
inhibition of calcitonin synthesis
The single most important regulator of calcium levels in the blood is ________.
parathyroid hormone
The prime metabolic effect of cortisol is gluconeogenesis.
t
Atrial natriuretic peptide is a hormone that controls blood pressure in part by increasing the urinary excretion of sodium.
T
Glucocorticoids are steroid hormones that usually enhance the immune responses when an individual is suffering from severe stress.
F
Gluconeogenesis occurs in the liver due to the action of ________.
cortisol
secretin
aldosterone
insulin
cortisol
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
Mineralocorticoid is to aldosterone as glucocorticoid is to ________.
cotisol
The most important regulator of electrolyte concentrations in extracellular fluids is ________.
aldosterone
Aldosterone ________.
functions to increase sodium reabsorption
Addison's disease is due to a insufficient output of glucocorticoids only.
f
Hypersecretion of catecholamines can result in hypertension.
t
How do glucocorticoids enable the body to deal appropriately with stress?
by increasing blood glucose, fatty acid, and amino acid levels and enhancing blood pressure
The pineal gland is used as a brain orientation landmark for brain X rays.
t
The hormone that raises blood sugar levels is insulin.
f
Type 2 diabetics may reflect declining receptor sensitivity to insulin rather than decreased insulin production.
t
Many hormones synthesized in the gastrointestinal tract are chemically identical to brain neurotransmitters.
t
Which organ is responsible for synthesizing ANP?
the heart
Leptin is secreted by ________.
adipocytes
A 25-year-old male was admitted to the medical/surgical unit with a blood glucose level of 600 mg/dl. On assessment, the nurse observed that his breathing was deep and rapid, and his breath smelled of acetone. His face was flushed, his skin was dry, and his pH was low. What is the diagnosis and what physiological response is occurring?
Diabetes mellitus. The nervous system responds by initiating rapid deep breathing to blow off carbon dioxide from the blood and increase pH.
Enteroendocrine cells of the GI tract produce some hormones that are chemically identical to neurotransmitters.
t
The beta cells in the pancreatic islets produce insulin.
t
Which of the following is not a cardinal sign of diabetes mellitus?
polycythemia
Which of the following hormones suppresses appetite and increases energy expenditure?
leptin
Normal development of the immune response is due in part to hormones produced by the ________.
thymus gland
In aged individuals, chronic stress may increase blood levels of cortisol and possibly contribute to memory deterioration.
t
Most type 2 diabetics do not produce insulin.
f
What part of the body does erythropoietin (EPO) target to increase erythropoiesis?
Bonemarrow
Identify the thyroid gland. Select from letters A-D.
A
What is the primary function of hormones?
alter cell activity
Which of the following mechanisms of hormone action is used by neurotransmitters and olfactory receptors?
cAMP
__________ is the situation when one hormone cannot exert its full effects without another hormone being present.
Permissiveness
The stimuli causing endocrine glands to secrete their hormones in direct response to changing blood levels of certain critical ions and nutrients are called __________.
humoral stimuli
Up-regulation involves the loss of receptors and prevents the target cells from overreacting to persistently high hormone levels.
f
The hypothalamus is known to control the activity of the anterior pituitary, which has traditionally been called the "master endocrine gland."
t
At which point does the hormone bind to its intracellular receptor? Determine the receptor-hormone complex. Select from letters A-D.
A
What amino acid-based hormone uses the direct gene activation method illustrated in this image?
thyroxine
Hyperprolactinemia may be caused by ______.
hyposecretion of dopamine
What is required for the production of anterior pituitary gland hormones?
hormonal stimuli
Hormones that regulate the secretory action of other endocrine glands are called __________.
tropins
What hormone released into the blood (shown by letter D) by the posterior pituitary inhibits or prevents urine formation?
antidiuretic hormone (ADH)
Hypersecretion of what hormone can produce the effects of gigantism (individual in the center of this image)?
growth hormone (GH)
What gland secretes growth hormone?
anterior pituitary (lobe)
Where is thyroid-releasing hormone (TRH) made? Select from letters A-D.
A
You would predict that iodized salt would have no effect on any cases of ____________.
Graves' disease
Which hormone is the body's major metabolic hormone?
thyroid hormone
What type of cell is shown at letter C?
follicular cells
What hormone is released by the cells pictured in letter D?
calcitonin
Osteitis fibrosa is a rare complication of hyperparathyroidism where the bones soften and deform.
t
Which of the following would result from hypoparathyroidism?
neurons become more excitable and tingling sensations
Aldosteronism will cause ______.
decreased secretion of renin
Cushing's syndrome and aldosteronism have the same effects on ______.
blood pressure
Which hormone(s) is/are essential to our ability to deal with stress?
glucocorticoids
Which of the following adrenal gland homeostatic imbalances is characterized by persistent elevated blood glucose levels, dramatic losses in muscle and bone protein, and water and salt retention, leading to hypertension and edema?
Cushing's syndrome
What hormone, notated by letter B, is released by the anterior pituitary to target the adrenal cortex when we are under stress?
adrenocorticotropic hormone (ACTH)
One can predict that a person suffering from diabetes mellitus would probably have ______.
increased secretion of ADH (anti-diuretic hormone)
Which of the following is NOT a property of endocrine glands?
They have ducts.
Which of the following is NOT an endocrine gland?
adenoid
Which letter represents the adrenal glands? Select from letters A-D.
C
Identify the pancreas. Select from letters A-D.
d
Which of the following is NOT a major type of stimulus that triggers endocrine glands to manufacture and release hormones?
enzymatic
Which of the following occurs in situations where more than one hormone produces the same effects at the target cell and their combined effects are amplified?
synergism
At what point does the receptor-hormone complex bind to DNA? Select from letters A-D.
c
A blow to the head may cause diabetes insipidus by ______.
interfering with the normal transmission of ADH to the posterior pituitary via the axons of hypothalamic neurons
Acromegaly may be caused by all EXCEPT which of the following?
positive feedback by GH (growth hormone) on the anterior pituitary
Which of the following is a hormone produced by the posterior pituitary?
none
Which of the following hormones stimulates the adrenal cortex to release glucocorticoids that help the body to resist stressors?
adrenocorticotropic hormone
Which of the following hormones mainly serves to stimulate milk production by the breasts?
prolactin
Which of the following hormones helps the body avoid dehydration and water overload?
antidiuretic hormone
Major hormones circulate to virtually all tissues.
t
The anatomical effects of acromegaly can usually be reversed by surgically removing the tumor from the anterior pituitary.
f
Where are the hormones oxytocin and antidiuretic hormone (ADH) stored? Select from letters A-D.
c
Which hypothalamic hormone stimulates the release of growth hormone from the anterior pituitary (lobe)?
growth hormone-releasing hormone (GHRH)
What is the target organ of thyroid-stimulating hormone (TSH)? Select from letters A-D.
c
What is the target organ of thyroid-releasing hormone (TRH)? Select from letters A-D.
b
Which of the following is NOT a homeostatic imbalance related to underactivity of the thyroid gland?
Graves' disease
Name two hormones produced by the gland identified by letter B.
thyroid hormones and calcitonin
Hypocalcemia could be caused by the ______.
all are correct
Which of the following hormones regulates blood calcium ion levels?
parathyroid hormone
What type of stimulation controls parathyroid release?
humoral
What cells release parathyroid hormone?
parathyroid cells
Two adrenal glands make hormones that are essential for life. However, in adrenogenital syndrome, females develop a beard and a masculine pattern of body hair distribution; this occurs due to ______.
lack of enzymes the adrenal gland needs to make cortisol and aldosterone
Pheochromocytoma produces symptoms of uncontrolled sympathetic nervous system activity. Which of the following is common to both adrenal chromaffin cells and adrenergic fibers of the sympathetic nervous system?
secretion of norepinephrine
Which of the following pairs correctly matches the adrenal gland zone or area with the class of hormones it produces?
zona glomerulosa: mineralocorticoids
Which of the following glands is found atop the kidneys?
adrenal
What factor inhibits aldosterone release? Select from letters A-D.
d
Which letter represents the hormone that promotes a decrease in blood pressure and a loss of sodium and water in urine? Select from letters A-D.
d
Which pancreatic hormone functions to lower blood glucose levels?
insulin
Which of the following structures does/does NOT produce a hormone or hormones?
lungs
Which of the following best describes the main effects of insulin?
lower blood glucose levels
Which of the following is a hypoglycemic hormone?
insulin
Which hormone is involved in diabetes mellitus (DM)?
insulin
Which of the following triggers the release of glucagon?
a decrease in blood glucose levels
Which hormone can indirectly control insulin release?
release of glucagon by the pancreatic islets
Which of the following best describes gluconeogenesis?
synthesis of glucose from noncarbohydrate sources
Hormones are long-distance chemical signals that travel in blood or lymph throughout the body.
t
Which of the following statements is most correct regarding the intracellular chemical signals known as "second messengers"?
Cyclic AMP and calcium may be second messengers.
Nitric oxide is known to be the first gas to act as a biological messenger.
t
Riboswitches are folded RNAs that act as switches to turn protein synthesis on or off in response to _________.
changes in the environment
Which of the following does not serve as a signal for cell division?
repressor genes
__________ is a substance in food used by the body to promote normal growth, maintenance, and repair.
A nutrient
Neurons and red blood cells rely exclusively on __________ to meet their energy needs.
glucose
__________ refers to reactions in which large molecules are broken down into smaller molecules.
Catabolism
Glycolysis occurs in the __________ of cells and is an __________ process.
cytosol; anaerobic
What is the primary function of cellular respiration - its end-purpose?
to generate ATP
Which nutrients are the most important anabolic nutrients?
amino acids
__________ is the key hormone regulator of the absorptive state.
insulin
The primary goal during the postabsorptive state is to __________.
maintain blood glucose levels within an adequate range
During ketosis caused by inadequate ingestion of carbohydrates, ______.
the glycogen content of the liver is reduced
Which nutrient molecule is the pivotal fuel molecule in the oxidative pathways?
glucose
Which of the following is NOT a pathway in the oxidation of glucose?
gluconeogenesis
Which term describes the breakdown of stored fats into glycerol and fatty acids?
lipolysis
The body's rate of kilocalorie consumption needed to fuel all ongoing activities is called the __________.
total metabolic rate
The hyperglycemia that occurs during diabetes mellitus is accompanied by ______.
ketosis
Which hormone directs essentially all events of the absorptive state?
insulin
Most ATP in cellular respiration is generated in glycolysis.
f
The body is able to form glucose from non-carbohydrate precursors.
t