Chapter 16 The Endocrine System (TB)

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

A) aldosterone
B) secretin
C) insulin
D) cortisol

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

A) thymus gland
B) pancreas
C) thyroid gland
D) adrenal medulla

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

A) deactivators
B) second messengers
C) nucleotides
D) ions

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

A) enzyme
B) neural
C) hormonal
D) humoral

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

A) antibodies
B) proteins
C) enzymes
D) hormones

The hypothalamic-hypophyseal tract ________.

A) connects the hypophysis to the pituitary gland
B) conducts aldosterone to the hypophysis
C) is the site of prolactin synthesis
D) is partly contained within the infundibulum

Which of the following is not a cardinal sign of diabetes mellitus?

A) All of these are signs.
B) polyphagia
C) polyuria
D) polydipsia

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

A) number of receptors for that hormone 
B) blood levels of hormone
C) type of hormone
D) strength of the bond between the receptor and hormone

Oxytocin ________.

A) controls milk production
B) exerts its most important effects during menstruation
C) release is an example of a positive feedback control mechanism
D) is an adenohypophyseal secretion

ADH ________.

A) is inhibited by alcohol
B) increases urine production
C) is produced in the adenohypophysis
D) promotes dehydration

Thyroid hormone exerts its influence by ________.

A) entering some cells and binding to intracellular receptors within the nuclei
B) exerting only a minor effect on body metabolism
C) acting to decrease basal metabolic rate
D) causing a reduction in the number of blood vessel adrenergic receptors, and therefore decreasing blood pressure

Gonadocorticoid(s) ________.

A) production by the adrenal gland is insignificant compared with sex hormone release from the gonads during late puberty
B) secretion inhibition is highly dependent on a negative feedback loop involving ACTH
C) hypersecretion can result in adrenogenital syndrome, also called feminization
D) synthesized by the adrenal medulla are primarily androgens

Sometimes prolonged excessive exposure to high hormone concentrations causes a phenomenon known as ________.

A) cellular inhibition
B) metabolism of protein kinases
C) down-regulation
D) diabetes mellitus

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

A) a change in membrane potential
B) an increase in enzymatic activity
C) the stimulation of a genetic event resulting in protein synthesis
D) 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 ________.

A) the membrane potential of the cells of the target organ
B) nothing all hormones of the human body are able to stimulate any and all cell types because hormones are powerful and nonspecific
C) the presence of the appropriate receptors on the cells of the target tissue or organ
D) the location of the tissue or organ with respect to the circulatory path

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 ________.

A) general circulatory system
B) hepatic portal system
C) hypophyseal portal system
D) feedback loop

The neurohypophysis or posterior lobe of the pituitary gland is not a true endocrine gland because ________.

A) embryonically it was an endocrine tissue, but in the adult human it is no longer functional
B) it is strictly a part of the neural system and has little or nothing to do with hormonal release
C) it is only a hormone storage area that receives hormones from the hypothalamus for release
D) it is unable to function as an endocrine tissue because it is actually part of the neural system due to its location

Steroid hormones exert their action by ________.

A) stimulating the synthesis of a glycogen
B) entering the nucleus of a cell and initiating or altering the expression of a gene
C) increasing blood pressure
D) finding an appropriate cell receptor and initiating cAMP activity

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

A) binding to specific receptors and employing the services of G proteins and cAMP
B) not responding to a feedback mechanism
C) increasing the basal metabolic rate in the target organ
D) synthesizing more of the hormone than is actually needed

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

A) during protein kinase activation, enzymes phosphorylate many other enzymes
B) the protein kinases are rapidly metabolized
C) there are thousands of receptors on the cell membrane
D) the receptors bind to several hormones at the same time

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 ________.

A) hormones alter cellular operations through stimulation of a gene directly
B) peptide hormones always enter the cell membrane and elicit a response without assistance from other messengers
C) G protein acts as the link between first and second messengers
D) the hormone receptor complex moves into the cytoplasm as a unit

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

A) growth hormone, because the thyroid works synergistically with thyroid hormone
B) steroid hormones, because both diffuse easily into target cells
C) glucagon, because the structure of glucagon is similar to that of thyroid hormone
D) insulin, because insulin is a small peptide

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 ________.

A) epinephrine
B) estrogen
C) renin
D) angiotensinogen

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?

A) humoral stimulation
B) protein synthesis
C) catabolic inhibition
D) the rapid oxidation of carbohydrates

The major targets of growth hormone are ________.

A) the adrenal glands
B) the blood vessels
C) the liver
D) bones and skeletal muscles

The parathyroid glands maintain adequate levels of blood calcium. This is accomplished through ________.

A) antagonizing the synthesis of calcitonin
B) targeting the bone and activating osteoclasts so that calcium will be released
C) slowing the activity of tissues that require calcium for activity
D) blocking the action of growth hormone

Which organ is responsible for synthesizing ANP?

A) the heart
B) the skin
C) the spleen
D) the kidney

Mineralocorticoid is to aldosterone as glucocorticoid is to ________.

A) estrogen
B) cortisol
C) testosterone
D) epinephrine

Leptin is secreted by ________.

A) fibroblasts
B) adipocytes
C) lymphocytes
D) goblet cells

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

A) insulin
B) glucagon
C) cortisol
D) aldosterone

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

A) estrogen
B) epinephrine
C) cortisone
D) aldosterone

Which of the following would be associated with the action of steroids on cells?

A) extracellular receptors with a specificity for only a single amino acid sequence on the hormone
B) second-messenger systems
C) an enzyme that catalyzes the formation of cyclic AMP
D) a hormone-receptor complex that interacts directly with the cell's DNA

Cellular responses to hormones that initiate second-messenger systems include ________.

A) cyclic AMP phosphodiesterase formation of an active second messenger
B) possible activation of several different second-messenger systems
C) hormone binding to intracellular receptors
D) formation of a specific protein kinase that acts on a series of extracellular intermediates

Regulating hormones from the hypothalamus ________.

A) first enter into the hypophyseal portal system
B) travel by arteries to the pituitary
C) enter the hepatic portal system, which feeds the pituitary
D) enter venous circulation and travel to the heart, which pumps the hormone-containing blood to the pituitary

ACTH ________.

A) is not a tropic hormone
B) secretion is regulated by a hypothalamic secretion
C) causes the release of hormones from the adrenal medulla
D) is secreted by the posterior pituitary

Which of the following is true about calcium homeostasis?

A) Increased calcitonin levels will cause increased blood calcium levels.
B) Parathyroid hormone is the single most important regulator of calcium levels in the blood.
C) High calcium levels cause bone resorption.
D) Parathyroid hormone causes an increase in osteoblast activity.

Aldosterone ________.

A) presence increases potassium concentration in the blood
B) functions to increase sodium reabsorption
C) is secreted by the neurohypophysis
D) production is greatly influenced by ACTH

The only amine hormone to act like a steroid is ________.

A) ADH
B) GH
C) TH
D) ACTH

Which organ does not have hormone production?

A) liver
B) heart
C) skin
D) kidney

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 ________.

A) up-regulation
B) the cell's sensitivity reaction
C) cellular affinity
D) a reaction to a stressor

Eicosanoids do not include ________.

A) hydrocortisones
B) prostaglandins
C) leukotrienes
D) paracrines

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.

A) FSH stimulates estrogen secretion by ovarian cells; therefore it is not synthesized by males.
B) The physician is wrong in a hormone made in the adenohypophysis could not influence fertility.
C) FSH stimulates sperm production in the testes.
D) The man must be producing progesterone, which inhibits the synthesis of FSH.

Which of the following organs is affected by thyroid hormone in adults?

A) liver
B) thyroid gland
C) brain
D) spleen

Thyroxine is a peptide hormone, but its mechanism is different from other peptide hormones. Which of the following statements is true concerning this difference?

A) It is a stimulant of cellular metabolism and targets all cells.
B) It causes positive feedback.
C) It does not require a second messenger to effect a response.
D) It is very specific in the cell type it targets.

How do glucocorticoids enable the body to deal appropriately with stress?

A) by blocking the neurotransmitters that prepare the body for the stress response
B) by decreasing the heart rate, thus decreasing blood pressure
C) by increasing blood glucose, fatty acid, and amino acid levels and enhancing blood pressure
D) by stimulating the pancreas to release insulin

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

A) sodium
B) calcium
C) iron
D) chlorine

________ are hormones synthesized from cholesterol.

________ is a hormone that has only one known effect: to stimulate milk production by the breasts.

________ are the result of hypersecretion of growth hormone.

The largest pure endocrine gland in the body is the ________.

Which hormone stimulates production of RBCs and which organ or structure produces it?

Alpha islet cells produce ________, an extremely potent hyperglycemic hormone.

The ________ gland may influence our day/night cycles and even regulate the onset of sexual maturity.

The ________ gland declines in size and function with age.

Endocrine gland stimuli include hormonal, ________, and ________ stimuli.

As a result of stress the adenohypophysis releases ________, which stimulates release of hormones from the adrenal cortex that retain sodium and water, increase blood sugar, and begin breaking down fats.

In humans, melatonin may inhibit sexual maturation. True or False
True False

The antagonistic hormones that regulate the blood calcium level are calcitonin-parathormone. True or False
True False

The hormone that raises blood sugar levels is insulin. True or False
True False

Addison's disease is due to a deficit output of glucocorticoids only. True or False
True False

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. True or False
True False

ACTH stimulates the adrenal cortex to release corticosteroid hormones. True or False
True False

LH is also referred to as a gonadotropin. True or False
True False

With age, chronic stress increases blood levels of cortisol and appears to contribute to memory deterioration. True or False
True False

Oxytocin is a strong stimulant of uterine contractions. True or False
True False

Follicle cells of the thyroid gland produce thyroglobulin, while follicle cells of the parathyroid produce calcitonin. True or False
True False

Type 2 diabetics may reflect declining receptor sensitivity to insulin rather than decreased insulin production. True or False
True False

The prime metabolic effect of cortisol is gluconeogenesis. True or False
True False

The beta cells are the pancreatic islet cells that produce insulin. True or False
True False

Most type 2 diabetics do not produce insulin. True or False
True False

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

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

Although glucagon is a small polypeptide, it is nevertheless very potent in its regulatory effects. True or False
True False

The thyroid gland is a large gland that controls metabolic functions throughout the life of an individual. True or False
True False

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

All of the following hormones are secreted by the adenohypophysis: ACTH, FSH, and LH. True or False
True False

Iodine is an essential element required for the synthesis of thyroxine. True or False
True False

The endocrine gland that is probably malfunctioning if a person has a high metabolic rate is the parathyroid. True or False
True False

Growth hormone always exerts its influence by targeting other endocrine glands to produce hormones. True or False
True False

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

Direct gene activation involves a second-messenger system. True or False
True False

All peptide hormone synthesis requires gene activation that produces mRNA. True or False
True False

All adenohypophyseal hormones except GH affect their target cells via a cyclic AMP second messenger. True or False
True False