What keeps intracellular receptors from binding to DNA before a hormone binds to the receptor?

chaperone proteins (chaperonins)

What type of hormones bind to receptors located on the cell membrane?

water-soluble hormones, such as insulin and epinephrine

Which intracellular substance degrades cAMP, thus inactivating the response to a hormone?

phosphodiesterase

Growth factor hormones, such as insulin, bind to which type of receptor?

tyrosine kinase receptors

Which is the correct order of events for hormones activating G_s proteins?

activation of G protein, binding of GTP, activation of adenylate cyclase, conversion of ATP to cAMP

Which second messenger causes the release of calcium from the endoplasmic reticulum?

IP₃

Which of the following adrenergic receptors increase cAMP levels?

β receptors

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

Some endocrine glands secrete their hormones in direct response to changing blood levels of certain critical ions and nutrients. These stimuli are called humoral stimuli to distinguish them from hormonal stimuli, which are also bloodborne chemicals.

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

Cushing's syndrome 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.

Which of the following hormones helps the body avoid dehydration and water overload?

antidiuretic hormone

Which hormone is the body's major metabolic hormone?

TH

Which hormone is the body's major metabolic hormone?

parathyroid hormone/calcitonin

Which of the following pairs correctly matches the adrenal gland zone or area with the class of hormones it produces?

zona glomerulosa: mineralocorticoids

When blood glucose levels are high

The pancreas releases insulin.

A liver cell responds to insulin by

Taking in glucose and converting it to glycogen.

A liver cell responds to insulin by

Taking in glucose and converting it to glycogen.

What cells in the body respond to glucagon by breaking down glycogen and releasing glucose?

Liver cells

Body cells that respond to insulin include

Liver cells, as well as most other cells of the body.

When blood glucose levels are low

The pancreas releases glucagon, which eventually causes blood glucose levels to increase.

The body's tendency to maintain relatively constant internal conditions is called

homeostasis.

Which pancreatic hormone functions to lower blood glucose levels?

insulin

Insulin, produced by the pancreatic beta cells, lowers blood glucose levels by enhancing membrane transport of glucose into body cells, inhibiting the breakdown of glycogen to glucose and inhibiting the conversion of amino acids and fats to glucose.

Adrenocortical androgens are normally converted in females into estrogens. However, in adrenogenital syndrome, females develop a beard and a masculine pattern of body hair distribution; this occurs due to ______.

insufficient level of enzymes that convert androgens into estrogens

During the end steps of sex hormone, synthesis androstendione is converted into either testosterone or estrogen. If the body lacks the enzyme to convert androstendione to estrogen, the remaining pathway to testosterone will predominate.

One can predict that a person suffering from diabetes mellitus would probably have ______.

increased secretion of ADH (anti-diuretic hormone)

Diabetes mellitus is a metabolic disorder resulting from a lack of insulin in the body. Insulin functions to lower blood glucose levels by enhancing the transport of glucose from the systemic circulation into cells. ADH is secreted in response to high blood osmolarity (too high solutes or too little water) in the blood. This hormone functions to increase the resorption of water by the kidneys, which dilutes the blood.

The amplification of the signal from a water-soluble hormone is achieved through an increase in _______.

cAMP in the cytoplasm

Many cAMP can be generated as a second messenger to amplify the signal in response to hormone binding.

Water-soluble hormones affect target cells by binding to __________.

plasma membrane receptors

Water-soluble hormones bind to specific receptors in the plasma membrane, whereas steroid hormones bind to cytoplasmic receptors.

How do endocrine hormones reach their target cells?

Hormones are transported through the blood stream to target cells.

The blood stream allows hormones to be distributed throughout the body.

What is the role of activated protein kinases?

Phosphorylate proteins.

Phosphorylation can activate different proteins causing the response of the cell to water-soluble hormone.

Cyclic AMP is degraded by __________.

phosphodiesterase

Phosphodiesterase degrades cyclic AMP into AMP.

Which of the following enzymes are important in the deactivation of cAMP and termination of signaling?

phosphodiesterase

What tropic hormone stimulates cortisol from the adrenal gland?

adrenocorticotropic hormone (ACTH)

Yes, ACTH stimulates the adrenal cortex to produce cortisol. Stress and ACTH are the main stimuli for cortisol.

What is the function of the ventral hypothalamic neurons?

control secretion of thyroid stimulating hormone (TSH)

Yes, neurohormones from the ventral hypothalamic neurons, known as releasing (RH) and inhibiting (IH) hormones, control the release of anterior pituitary hormones such as adrenocorticotropic hormone (ACTH) and TSH.

Insulin-like growth factors (IGFs) are intermediary hormones stimulated by which of the following hormones?

GH (growth hormone)

Yes, GH stimulates IGFs from the liver. IGFs are required for the growth effect of GH on bone and skin.

Which of the following hormones is regulated by a neuroendocrine (“letdown”) reflex?

oxytocin

Yes, suckling of the infant (or stretching of the uterus) increases release of oxytocin, which causes the milk let-down effect (or increased uterine contractions).

Where is antidiuretic hormone (ADH), also known as vasopressin, synthesized?

hypothalamus

Yes, ADH is synthesized mainly in the supraoptic nucleus of the hypothalamus. It is stored in the posterior pituitary in axon terminals.

What is the most important regulatory factor controlling the circulating levels of thyroid hormone?

negative feedback

Yes, negative feedback controls the levels of circulating thyroid hormone. If levels are high, negative feedback will decrease thyroid-stimulating hormone (TSH) (and thyrotropin-releasing hormone (TRH) to some degree), thus decreasing the thyroid hormones.

Which of the following hormones is a part of the rapid response (rather than the prolonged response) to stress?

epinephrine

Yes, epinephrine is part of the immediate or rapid response to stress. Epinephrine is released from the adrenal medulla as a result of the increase in the sympathetic nervous system. In fact, the chromaffin cells in the adrenal medulla act like modified postganglionic neurons.

In response to stress, which of the following changes would happen?

decreased insulin secretion

Yes, insulin decreases plasma glucose and during stress we need an increase in plasma glucose as well as other body fuels. Therefore, insulin secretion would be decreased, in turn increasing plasma glucose.

Which of the following are symptom(s) of pheochromocytoma?

heart palpitations

Yes, due to the increase in epinephrine, heart rate would be increased and you would feel like your heart was pounding or racing.

Choose which condition has all of the following symptoms: hypertension, hyperglycemia, and a “moon face.”

Cushing’s disease

Yes, a patient with Cushing’s would have hypertension, increased blood glucose, and an unusual fat distribution on the face, known as a “moon face.” These symptoms are due to increased levels of cortisol and can also be seen in patients after long periods of steroid treatment.

What hormone also aids the stress response by promoting water retention and acting as a vasoconstrictor?

ADH (vasopressin)

Yes, ADH increases water reabsorption in the distal tubule and collecting duct of the nephron and its secondary function is to act as a vasoconstrictor.

target cells do not respond normally to insulin.

type 2 diabetes

no insulin is produced.

type 1 diabetes

glucose levels remain higher than normal.

both

Normal development of the immune response is due in part to hormones produced by the ________.

thymus gland

Which of the following is NOT a property of endocrine glands?

They have ducts.

Endocrine glands are ductless glands.

Which of the following is NOT an endocrine gland?

adenoid

Pharyngeal tonsils, when enlarged, are commonly called adenoids and are lymphoid tissue, not endocrine glands.

Chemical substances secreted by cells into the extracellular fluids and that regulate the metabolic function of other cells in the body are called ________.

hormones

Which of the following mechanisms of hormone action is used by neurotransmitters and olfactory receptors?

cAMP

cAMP is the hormone mechanism used by neurotransmitters and olfactory receptors.

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

Synergism of hormones occurs in situations where one or more hormones produce the same effect at the target cell and their combined effects are amplified.

__________ is the situation when one hormone cannot exert its full effects without another hormone being present.

Permissiveness

Permissiveness occurs when one hormone cannot exert its full effects without another hormone being present.

Hormones that regulate the secretory action of other endocrine glands are called __________.

tropins

Tropins, or tropic hormones, are hormones that regulate the secretory action of other endocrine glands.

Which of the following hormones stimulates the adrenal cortex to release glucocorticoids that help the body to resist stressors?

adrenocorticotropic hormone

Adrenocorticotropic hormone (ACTH) stimulates the adrenal cortex to release corticosteroid hormones, most importantly glucocorticoids that help the body to resist stressors.

Which of the following hormones mainly serves to stimulate milk production by the breasts?

prolactin

Prolactin (PL) stimulates the mammary glands of the breasts to produce milk.

What is the primary function of hormones?

alter cell activity

The primary function of hormones is to alter cell activity by altering plasma membrane permeability or membrane potential, stimulating synthesis of enzymes or regulating molecules, activating or deactivating enzymes, inducing secretory activity, or stimulating mitosis.

Which of the following is NOT a major type of stimulus that triggers endocrine glands to manufacture and release hormones?

enzymatic

Enzymes are not triggers in the release of hormones.

Which of the following is not a type of hormone interaction?

feedback

Which of the following is not a change typically produced by a hormonal stimulus?

stimulates production of an action potential

Which of the following is not a change that may be caused by hormonal stimulus?

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

Steroid hormones exert their action by ________.

entering the nucleus of a cell and initiating or altering the expression of a gene

The second-messenger mechanism of hormone action operates by ________.

binding to specific receptors and employing the services of G proteins and cAMP

Hormones often cause a cell to elicit multiple responses; this is because ________.

during protein kinase activation, enzymes phosphorylate many other enzymes

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

Thyroid hormone (a small iodinated amine) enters target cells in a manner similar to ________.

steroid hormones, because both diffuse easily into target cells

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

Virtually all of the protein or amino acid-based hormones exert their effects through intracellular ________.

second messengers

Which of the following is not a steroid-based hormone?

epinephrine

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

Eicosanoids do not include ________.

hydrocortisones

Which of the following is not a category of endocrine gland stimulus?

enzyme

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.

What ion is sometimes used as a second messenger of amino acid–based hormones?

calcium

Which of the choices below is not a factor required for target cell activation by hormone receptor interaction?

type of hormone

Direct gene activation involves a second-messenger system.

F

All peptide hormone synthesis requires gene activation that produces mRNA.

T

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

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)

Which hypothalamic hormone stimulates the release of growth hormone from the anterior pituitary (lobe)?

growth hormone-releasing hormone (GHRH)

Which of the following is NOT a homeostatic imbalance related to underactivity of the thyroid gland?

Graves' disease

The most common hyperthyroid pathology is an autoimmune disease called Graves' disease. In this condition, a person makes abnormal antibodies directed against thyroid follicle cells.

Which of the following glands is found atop the kidneys?

adrenal

Hormones are long-distance chemical signals that travel in blood or lymph throughout the body.

T

Major hormones circulate to virtually all tissues.

T

A blow to the head may cause diabetes insipidus by ______.

interfering with the normal transmission of nerve impulses to the posterior pituitary

Specialized neurons of hypothalamus, called the periventricular nuclei, produce anti-diuretic hormone. Then it is transported, stored, or released from axon endings located in the posterior pitutary.

Acromegaly may be caused by all EXCEPT which of the following?

positive feedback by GH (growth hormone) on the anterior pituitary

Acromegaly is a disorder in which there is too much growth hormone and the body tissues gradually enlarge. Growth hormone secretion is stimulated by GHRH (growth hormone-releasing hormone).

Hyperprolactinemia may be caused by ______.

hyposecretion of dopamine

Dopamine functions as a prolactin-release-inhibiting hormone (PIH).

Which of the following is a hormone produced by the posterior pituitary?

ADH

oxytocin

HGH

none of these

None of the hormones given is produced by the posterior pituitary.

What is required for the production of anterior pituitary gland hormones?

hormonal stimuli

The anterior pituitary requires hormonal stimuli from the hypothalamus.

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.

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

91. 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.

The hypothalamic-hypophyseal tract ________.

is partly contained within the infundibulum

Oxytocin ________.

release is an example of a positive feedback control mechanism

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 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

Up-regulation involves the loss of receptors and prevents the target cells from overreacting to persistently high hormone levels.

F

You may predict that iodized salt may be effective in preventing all EXCEPT which of the following?

Graves' disease

Graves' disease occurs due to hyperthyroidism. Iodine is an important precursor for the production of thyroid hormone.

Thyroid hormone production requires the presence of iodine and calcium.

F

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

What type of stimulation controls parathyroid release?

humoral

Which of the following would result from hypoparathyroidism?

neurons become more excitable and tingling sensations

What cells release parathyroid hormone?

parathyroid cells

The hypothalamus is known to control the activity of the anterior pituitary, which has traditionally been called the "master endocrine gland."

T

Hypocalcemia could be caused by the ______.

apoptosis of chief cells

failure of osteoclasts to respond to PTH (parathyroid hormone/parathormone)

malfunction of the parathormone receptors in kidney tubule cells

All of the listed responses are correct.

Parathyroid hormone (parathormone) is secreted in response to hypocalcemia. It functions to stimulate osteoclast activity, enhances the reabsorption of calcium by the kidneys, and increases absorption of calcium by the intestinal mucosal cells.

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

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)

The anatomical effects of acromegaly can usually be reversed by surgically removing the tumor from the anterior pituitary.

F

Hyperparathyroidism is a rare condition where the bones soften and deform.

T

Aldosteronism will cause ______.

decreased secretion of renin

Aldosteronism is due to oversecretion of aldosterone. The kidneys release renin, which is converted into angiotensin II which stimulates aldosterone release.

Cushing's syndrome and aldosteronism have the same effects on ______.

blood pressure

Cushing's syndrome results from excessive exposure to the hormone cortisol. Cortisol increases blood pressure by increasing the sensitivity of the blood vessels to epinephrine and norepinephrine. Aldosteronism occurs due to oversecretion of aldosterone. One function of aldosterone is to indirectly stimulate the reabsorbtion of water from the kidney tubule cells into the systemic circulation. This process increases blood volume and thus blood pressure.

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

Adrenal chromaffin cells are capable of releasing the neurotransmitters epinephrine and norepinephrine into systemic circulation. Post-ganglionic neurons of the symphathetic nervous system release norepinephrine only.

Which hormone(s) is/are essential to our ability to deal with stress?

glucocorticoids

Essential to life, the glucocorticoids increase blood glucose levels and help us to resist stressors.

Gluconeogenesis occurs in the liver due to the action of ________.

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 ________.

cortisol

The most important regulator of electrolyte concentrations in extracellular fluids is ________.

aldosterone

Aldosterone ________.

functions to increase sodium reabsorption

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 prime metabolic effect of cortisol is gluconeogenesis.

T

Aldosterone is the most potent mineralocorticoid produced in the adrenals but the least abundant.

F

Atrial natriuretic peptide is a hormone that controls blood pressure in part by increasing the urinary excretion of sodium.

T

Hypersecretion of catecholamines can result in hypertension.

T

Glucocorticoids are steroid hormones that usually enhance the immune responses when an individual is suffering from severe stress.

F

Addison's disease is due to a insufficient output of glucocorticoids only.

F

The pineal gland is used as a brain orientation landmark for brain X rays.

T

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 of the following hormones is responsible for diabetes mellitus (DM)?

insulin

Which of the following triggers the release of glucagon?

a decrease in blood glucose levels

Which of the following represents hormonal control of insulin release?

release of glucagon by the pancreatic islets

Which of the following best describes gluconeogenesis?

synthesis of glucose from noncarbohydrate sources

Which of the following structures do/does NOT produce a hormone or hormones?

lungs

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.

Which of the following hormones suppresses appetite and increases energy expenditure?

leptin

Which organ is responsible for synthesizing ANP?

the heart

Leptin is secreted by ________.

adipocytes

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

Most type 2 diabetics do not produce insulin.

F

Many hormones synthesized in the gastrointestinal tract are chemically identical to brain neurotransmitters.

T

The hormone that raises blood sugar levels is insulin.

F