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70 Cards in this Set
- Front
- Back
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Which of the following is NOT a major endocrine organ, but produces hormones in addition to its major function?
a) Kidneys b) Pituitary c) Pancreas d) Thymus |
Answer:
Kidneys REASONING: Kidney cells produce the hormones renin and erythropoietin, but their primary function is excretion of body waste. |
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Steroid hormones influence cellular activities by:
a)changing the permeability of the cell membrane. b)using calcium ions as a second-messenger. c)binding to DNA and forming a gene-hormone complex. d) activating cyclic AMP located outside the cell. e) activating cyclic AMP located inside the cell. |
Answer:
binding to DNA and forming a gene-hormone complex. REASONING:Steroid hormones enter the cell and form a DNA/hormone complex before they change cellular function. |
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Sympathetic nerve stimuli are responsible for the release of:
a)thyroid hormone. b) insulin. c) aldosterone. d) epinephrine. e)estrogen. |
Answer:
epinephrine. REASONING: The preganglionic fibers of the sympathetic neurons stimulate the adrenal medulla to produce epinephrine and norepinephrine. |
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The chemical classification of hormones does NOT include:
a) amino acid-based hormones. b) steroid hormones. c) cholesterol-containing hormones. d) protein-based hormones. e) glucose-containing hormones. |
Answer:
glucose-containing hormones. REASONING: The chemical classification of hormones is either amino acid-based hormones or steroids. |
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The metabolic rate of most body tissues is controlled directly by:
a) ADH. b) TSH. c) TH. d) ACTH e) FSH. |
Answer:
TH. REASONING:Thyroid hormones control the consumption of oxygen by all body tissues, by way of an increase in glucose metabolism. |
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The secretion of parathyroid hormone is a good example of:
a) neural stimuli. b) pituitary gland stimuli. c) hormonal stimuli. d) humoral stimuli. e) hypothalamic stimuli. |
Answer:
humoral stimuli REASONING: The declining levels of calcium ions in the blood control secretion of PTH. |
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The stimulus for producing insulin is:
a) low glycogen concentration. b) low blood fatty acid concentration. c) low blood amino acid concentration. d) high blood glucose concentration. e) low blood glucose concentration. |
Answer:
high blood glucose concentration. REASONING: Excess glucose levels in the blood stimulate Beta cells in the pancreas to secrete insulin. |
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The transcription of new messenger RNA is a function of:
a) catecholamines. b) pituitary gland hormones. c) steroid hormones. d) pancreatic hormones. e) amino acid-based hormones. |
Answer:
steroid hormones. REASONING: A steroid hormone complex controls the formation of new messenger RNA. |
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Which of the following elements is required for the synthesis of thyroid hormone?
a) Iodine b) Iron c) Sulfur d) Zinc e) Copper |
Answer:
Iodine REASONING: The production of functional thyroid hormone requires the presence of iodine. |
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The hypophyseal portal system transports releasing and inhibiting hormones from the hypothalamus to the:
a) thyroid gland. b) adrenal glands. c) ovaries. d) parathyroid glands. e) anterior pituitary gland (adenohypophysis). |
Answer:
anterior pituitary gland (adenohypophysis). REASONING: It is by this portal system that releasing and inhibiting hormones secreted by neurons in the ventral hypothalamus circulate to the adenohypophysis, where they regulate secretion of its hormones. |
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Which of the following signals would affect local cells by releasing chemicals into the extracellular fluid?
a) Endocrine b) Autocrine c) Paracrine d) Neural |
Answer:
Paracrine REASONING:Paracrine signals are local signals. |
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Which of the following is the property in which a hormone CANNOT exhibit its full effect without another hormone?
a) Permissiveness b) Assertiveness c) Synergism d) Antagonism |
Answer:
Permissiveness REASONING: Permissiveness is when a hormone needs another to be fully effective |
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Which of the following is NOT a true hormone, but, rather, a trophic substance?
a) Glucagon b) Aldosterone c) Thyroid hormone d) TSH e) Calcitonin |
Answer:
TSH REASONING: A "stimulating hormone" is NOT a true hormone. It causes the release of another hormone. |
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Which of the following organs is considered a neuroendocrine organ?
a) Pancreas b) Adrenal gland c) Pituitary d) Hypothalamus |
Answer:
Hypothalamus REASONING: The hypothalamus is considered a neuroendocrine organ. |
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Eicosanoids are not true hormones because they:
a) are lipid in nature. b) they act locally, not on distal organs as do true hormones. c) don't have target organs. d) mediate inflammatory reactions. |
Answer:
they act locally, not on distal organs as do true hormones. REASONING: Eicosanoids are not true hormones because they act locally, rather than on distal organs as do true hormones. |
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How do protein kinases affect enzymes?
a) They add a phosphate group (phosphorylation) to the enzyme. b) They increase the release of an enzyme. c) They increase the secretion of an enzyme. d) They break down the enzyme. |
Answer:
They add a phosphate group (phosphorylation) to the enzyme. REASONING:They cause phosphorylation of the enzyme that either activates or inhibits it. |
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The "hormone response element" is located on the cell:
a) DNA. b) RNA. c) enzymes. d) membrane. |
Answer:
DNA. REASONING: The "hormone response element" is located on the cell DNA and represents the site for a hormone to bind. |
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The binding of a hormone to its "hormone response element" would lead to the:
a) direct activation of second-messenger agents in the cell. b) direct activation of enzymes in the cell. c) formation of cAMP. d) transcription of the DNA for the gene that is "turned on" by this event. |
Answer:
transcription of the DNA for the gene that is "turned on" by this event. REASONING: The binding of a hormone to its "hormone response element" would lead to the transcription of the DNA for the gene that is "turned on" by this event. |
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Water-soluble hormones exhibit the shortest:
a) activation time. b) half-life. c) chain of amino acids. d) molecule. |
Answer:
half-life. REASONING: Water-soluble hormones exhibit the shortest half-life. |
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The normal endocrine controls can be directly overridden by the _________ system.
a) Reproductive b) digestive c) nervous d) circulatory |
Answer:
nervous REASONING: The normal endocrine controls can be directly over-ridden by the nervous system. |
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POMC is a prohormone for:
a) insulin. b) ACTH. c) growth hormone. d) thyroxin. |
Answer:
ACTH. REASONING:POMC is a prohormone for ACTH. |
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Excess growth hormone would cause all the following, except:
a) diabetes. b) acromegally in adults. c) suppression of cancer. d) giantism in children. |
Answer:
suppression of cancer. REASONING:Excess growth hormone is actually thought to promote cancer. |
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Hypersecretion of ADH can occur in all of the following situations, except:
a) after neurosurgery. b) damage to the pineal gland. c) ectopic ADH secretion by pulmonary cancer. d) after general anesthesia. |
Answer:
damage to the pineal gland. REASONING:Hypersecretion of ADH can occur from ectopic ADH secretion by pulmonary cancer. |
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Iodination of thyroid hormones is mediated by:
a) the Golgi apparatus b) colloid endocytosis. c) lysosomes in the cell. d) peroxidase enzymes. |
Answer:
peroxidase enzymes. REASONING:Peroxidase enzymes mediate iodination of thyroid hormones. |
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A congenital condition that includes mental retardation, short disproportional body size, and a thick tongue and neck is caused by:
a) excess of synthetic growth hormone. b) deficiency of thyroxin. c) insulin deficiency. d) deficiency of thymosin. |
Answer:
deficiency of thyroxin. REASONING:An excess of synthetic growth hormone might cause skeletal abnormalities, but has not been associated with mental retardation. |
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Osteitis fibrosa cystica is caused by:
a) an increase in calcitonin. b) an increase in the growth hormone in an adult. c) an increase in ADH. d) an increase in the parathyroid hormone. |
Answer:
an increase in the parathyroid hormone. REASONING:An increase in calcitonin would not cause osteitis fibrosa cystica. |
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Insulin enhances the membrane transport of glucose in all of the following, except the:
a) skeletal muscle. b) myocardium. c) adipose. d) brain. |
Answer:
brain. REASONING:Insulin enhances the membrane transport of glucose in all of the these tissues, except the brain. |
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Resistin, an insulin antagonist, is a hormone produced by the:
a) adipose tissue. b) hypothalamus. c) heart. d) liver. |
Answer:
adipose tissue. REASONING:Resistin is a hormone produced by the adipose tissue |
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Which of the following hormones does the skin produce?
a) Erythropoietin b) Cholecalciferol c) Melatonin d) Rennin |
Answer:
Cholecalciferol REASONING:Melatonin is produced by the pineal gland. |
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Somatostatin is considered paracrine because it acts on:
a) distant target organs. b) cells other than those that secrete it. c) the hypothalamus to inhibit or activate the secretion of other hormones. d) the cells that secrete it. |
Answer:
cells other than those that secrete it. REASONING:Somatostatin acts locally on cells other than those that secrete it and is therefore referred to as a paracrine hormone. |
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Drinking alcoholic beverages decreases urine output because it causes increased activity by ADH.
a) True b) False |
Answer:
False REASONING:Alcohol intake inhibits the secretion of ADH. It is the absence of ADH that increases urine output. |
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FSH and LH cause the maturation of the follicle cells of the thyroid gland.
a) True b) False |
Correct Answer:
False REASONING:These two hormones regulate the production of sperm and oocytes. |
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Sympathetic nerve stimulation causes the release of epinephrine and norepinephrine from the adrenal medulla.
a) True b) False |
Answer:
True REASONING:The adrenal medulla is a neurally stimulated gland. |
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The destruction of beta cells of the pancreas is an autoimmune condition characteristic of adult onset diabetes.
a)True b) False |
Correct Answer:
False REASONING:An autoimmune response is said to be the cause for type I diabetes. |
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The hormones of the thymus gland are essential in the formation of immune cells.
a) True b) False |
Correct Answer:
True REASONING:T lymphocytes, the main cells of the immune system, mature in the thymus gland, where they are stimulated by thymosin hormones. |
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The pancreas is considered both an endocrine and an exocrine gland.
a) True b) False |
Answer:
True REASONING:The secretion of digestive enzymes is an exocrine function, and the production of insulin and glucagon is an endocrine function. |
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The secretion of melatonin follows a night-day cycle, becoming low at night and high during daylight.
a) True b) False |
Answer:
False REASONING:The blood level of melatonin is high at night and low during daylight hours. |
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The skin, the heart, and the kidneys contain cells or tissues that produce hormones.
a) True b) False |
Correct Answer:
True REASONING:All the organs listed contain hormone-producing cells. |
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The synthesis and release of most hormones are regulated by a positive-feedback system.
a) True b) False |
Answer:
False REASONING:Blood levels of most hormones are regulated by a negative-feedback system. |
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The target tissues for oxytocin are the smooth muscle cells of the uterus and the myoepithelial cells of the mammary glands.
a) True b) False |
Answer:
True REASONING: The uterus contracts and the mammary glands eject the milk when stimulated by oxytocin. |
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Hormones are chemical substances secreted into synapses by neurons.
a) True b) False |
Answer:
False REASONING:Hormones are secreted into the extracellular fluids. |
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Most hormones can be classified chemically as either amino-acid based or steroids.
a) True b) False |
Answer:
True REASONING:Most hormones belong to the amino-acid group, while most others (steroids) are derived from cholesterol. |
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Hormones are "long-distance" chemical signals that travel in blood or lymph throughout the body.
a) True b) False |
Answer:
True REASONING:Most biologists agree that hormones are "long-distance" chemical signals, NOT local signals. |
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Local hormones are secreted into the blood to travel to their destinations.
a) True b) False |
Correct Answer:
False REASONING:Local hormones are released into the extracellular fluid and affect only adjacent cells in the same tissue. |
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Hormones that are derived from cholesterol are called steroids.
a) True b) False |
Answer:
True REASONING:Steroids are synthesized from cholesterol. |
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Hormones may communicate with their target cells by binding to an extracellular receptor.
a) True b) False |
Answer:
True REASONING:This mechanism is used by amino-acid hormones. |
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Hormones may communicate with their target cells by direct gene activation.
a) True b) False |
Correct Answer:
True REASONING:This is the mechanism used by steroid hormones |
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A hormone will affect all cells of the body.
a) True b) False |
Answer:
False REASONING:Even though all major hormones circulate to virtually all tissues, a given hormone influences only certain cells referred to as "target cells." |
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The hypothalamus regulates activity of the pituitary gland.
a) True b) False |
Answer:
True REASONING:The hypothalamus controls anterior pituitary (adenohypophysis) activity and the release of hormones from the posterior pituitary (neurohypophysis). |
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Thymic hormones are involved in calcium regulation.
a) True b) False |
Answer:
False REASONING:Thymic hormones are involved in immunity. |
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A hormone that exhibits antagonism will increase the action of another hormone.
a) True b) False |
Answer:
False REASONING:Antagonism has an opposite affect. |
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Endocrinology involves the study of the endocrine organs and ______________.
a) paracrines b) hormones c) autocrines d) neurotransmitters |
Answer:
hormones |
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Which of the following is not an endocrine gland?
a) Adrenal gland b) Thyroid gland c) Adenoid gland d) Pituitary gland |
Answer:
Adenoid gland |
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Autocrines are long-distance chemical signals that travel in blood or lymph throughout the body.
a) True b) False |
Correct Answer:
False See page 595. Hormones are long-distance chemical signals that travel in blood or lymph throughout the body. Autocrines are chemicals that exert their effects on the same cells that secrete them. |
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Steroids are synthesized from:
a) cholesterol. b) peptides. c) amino acids. d) proteins. |
Answer:
cholesterol. |
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Any given hormone will influence the activity of ___________.
a) its receptor cells b) its effector cells c) its target cells d) all tissue cells |
Answer:
its target cells |
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In which of the following mechanisms of hormone action do intracellular calcium ions act as a final mediator?
a) cGMP b) PIP2-calcium signaling mechanism c) cAMP d) DAG |
Correct Answer:
PIP2-calcium signaling mechanism See page 598. Cyclic AMP is the activating second messenger in some tissues for at least ten amino acid-based hormones, but some of the same hormones (such as epinephrine) act through a different second-messenger system in other tissues. In one such mechanism, called the PIP2-calcium signaling mechanism, intracellular calcium ions act as a final mediator. |
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Down-regulation involves the loss of receptors and prevents the target cells from overreacting to persistently high hormone levels.
a) True b) False |
Answer:
True |
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When one hormone opposes the action of another hormone, the interaction is called _____.
a) antagonism b) synergism c) organism d) permissiveness |
Answer:
antagonism |
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Which of the following occurs within a negative feedback system?
a) Target organ effects inhibit further hormone release. b) As hormone levels rise, hormone release is promoted. c) As hormone levels decrease, hormone release is inhibited. d) As hormone levels decrease, hormone release is promoted. |
Correct Answer:
Target organ effects inhibit further hormone release. See page 600. The synthesis and release of most hormones are regulated by some type of negative-feedback system. In such a system, some internal or external stimulus triggers hormone secretion. As hormone levels rise, they cause target organ effects, which then inhibit further hormone release. As a result, blood levels of many hormones vary only within a narrow range. |
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Which of the following is not one of the three major types of stimuli to trigger endocrine glands to manufacture and release their hormones?
a) neural stimuli b) endocrinal stimuli c) humoral stimuli d) hormonal stimuli |
Correct Answer:
endocrinal stimuli See page 600. Three major types of stimuli trigger endocrine glands to manufacture and release their hormones: humoral, neural, and hormonal stimuli. |
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The anterior pituitary is known as the "master endocrine gland" because it controls the hypothalamus.
a) True b) False |
Answer:
False |
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Which of the following stimulates most body cells to increase in size and divide?
a) Tropins b) Pro-opiomelanocortin c) Growth hormone d) Melanocyte-stimulating hormone |
Answer:
Growth hormone |
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Which of the following homeostatic imbalances results from hyposecretion of growth hormone?
a) Pituitary dwarfism b) Acromegaly c) Elephantiasis d) Gigantism |
Answer:
Pituitary dwarfism |
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Which of the following hormones stimulates gamete (sperm or egg) production?
a) Thyroid-stimulating hormone b) Follicle-stimulating hormone c) Growth hormone d) Prolactin |
Answer:
Follicle-stimulating hormone |
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As blood levels of ___________ rise, the expulsive contractions of labor gain momentum and finally end in birth.
a) oxytocin b) follicle-stimulating hormone c) prolactin d) gonadotropins |
Answer:
oxytocin |
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Which of the following is not one of the areas in which thyroid hormone (TH) plays an important role?
a) Helping the body avoid dehydration and water overload b) Regulating tissue growth and development c) Maintaining blood pressure d) Normal skeletal and nervous system development and maturation |
Answer:
Helping the body avoid dehydration and water overload |
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The cells found within the parathyroid gland that secrete parathyroid hormone are called _______.
a) follicle cells b) oxyphil cells c) chief cells d) parafollicular cells |
Correct Answer:
chief cells See page 612. The parathyroid's glandular cells are arranged in thick, branching cords containing scattered oxyphil cells and large numbers of smaller chief cells. The chief cells secrete parathyroid hormone. The function of the oxyphil cells is unclear. |
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Which of the following conditions, if left untreated, progresses to respiratory paralysis and death?
a) Hypoparathyroidism b) Hyperparathyroidism c) Hyperthyroidism d) Hypothyroidism |
Answer:
Hypoparathyroidism |
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Which of the following homeostatic imbalances usually results from deficits in both glucocorticoids and mineralocorticoids?
a) Cushing's syndrome b) Addison's disease c) Cretinism d) Graves' disease |
Correct Answer:
Addison's disease See page 618. Addison's disease, the major hyposecretory disorder of the adrenal cortex, usually involves deficits in both glucocorticoids and mineralocorticoids. Its victims tend to lose weight; their plasma glucose and sodium levels drop, and potassium levels rise. Severe dehydration and hypotension are common. |
