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53 Cards in this Set
- Front
- Back
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Cellular responses to hormones that initiate second-messenger systems include ________.
A) possible activation of several different second-messenger systems B) hormone binding to intracellular receptors C) formation of a specific protein kinase that acts on a series of extracellular intermediates D) cyclic AMP phosphodiesterase formation of an active second messenger |
A) possible activation of several different second-messenger systems
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ACTH ________.
A) is not a tropic hormone B) is secreted by the posterior pituitary C) causes the release of hormones from the adrenal medulla D) secretion is regulated by a hypothalamic secretion |
D) secretion is regulated by a hypothalamic secretion
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The most important regulator of electrolyte concentrations in extracellular fluids is ________.
A) cortisol B) aldosterone C) glucagon D) insulin |
B) aldosterone
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Which organ does not have hormone production?
A) liver B) skin C) heart D) kidney |
A) liver
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Which of the following is not a change that may be caused by hormonal stimulus?
A) an increase in enzymatic activity B) a change in membrane potential C) direct control of the nervous system D) the stimulation of a genetic event resulting in protein synthesis |
C) direct control of the nervous system
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Which organ is responsible for synthesizing ANP?
A) the skin B) the kidney C) the spleen D) the heart |
D) the heart
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Normal development of the immune response is due in part to hormones produced by the ________.
A) adrenal medulla B) thyroid gland C) pancreas D) thymus gland |
D) thymus gland
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Thyroid hormone exerts its influence by ________.
A) entering some cells and binding to intracellular receptors within the nuclei B) causing a reduction in the number of blood vessel adrenergic receptors, and therefore decreasing blood pressure C) exerting only a minor effect on body metabolism D) acting to decrease basal metabolic rate |
A) entering some cells and binding to intracellular receptors within the nuclei
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Sometimes prolonged excessive exposure to high hormone concentrations causes a phenomenon known as ________.
A) metabolism of protein kinases B) diabetes mellitus C) down-regulation D) cellular inhibition |
C) down-regulation
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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) catabolic inhibition B) the rapid oxidation of carbohydrates C) protein synthesis D) humoral stimulation |
D) humoral stimulation
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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) angiotensinogen B) estrogen C) epinephrine D) renin |
C) epinephrine
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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) FSH stimulates sperm production in the testes. C) The man must be producing progesterone, which inhibits the synthesis of FSH. D) The physician is wrong a hormone made in the adenohypophysis could not influence fertility. |
B) FSH stimulates sperm production in the testes.
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Which of the following is not a category of endocrine gland stimulus?
A) neural B) humoral C) hormonal D) enzyme |
D) enzyme
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The major targets of growth hormone are ________.
A) the liver B) the adrenal glands C) bones and skeletal muscles D) the blood vessels |
C) bones and skeletal muscles
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Chemical substances secreted by cells into the extracellular fluids and that regulate the metabolic function of other cells in the body are called ________.
A) proteins B) hormones C) antibodies D) enzymes |
B) hormones
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Steroid hormones exert their action by ________.
A) finding an appropriate cell receptor and initiating cAMP activity B) increasing blood pressure C) entering the nucleus of a cell and initiating or altering the expression of a gene D) stimulating the synthesis of a glycogen |
C) entering the nucleus of a cell and initiating or altering the expression of a gene
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Hormones often cause a cell to elicit multiple responses; this is because ________.
A) there are thousands of receptors on the cell membrane B) during protein kinase activation, enzymes phosphorylate many other enzymes C) the protein kinases are rapidly metabolized D) the receptors bind to several hormones at the same time |
B) during protein kinase activation, enzymes phosphorylate many other enzymes
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ADH ________.
A) is inhibited by alcohol B) is produced in the adenohypophysis C) increases urine production D) promotes dehydration |
A) is inhibited by alcohol
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Gluconeogenesis occurs in the liver due to the action of ________.
A) cortisol B) aldosterone C) secretin D) insulin |
A) cortisol
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The neurohypophysis or posterior lobe of the pituitary gland is not a true endocrine gland because ________.
A) it is strictly a part of the neural system and has little or nothing to do with hormonal release B) embryonically it was an endocrine tissue, but in the adult human it is no longer functional 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 |
C) it is only a hormone storage area that receives hormones from the hypothalamus for release
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Virtually all of the protein or amino acid-based hormones exert their effects through intracellular ________.
A) second messengers B) ions C) nucleotides D) deactivators |
A) second messengers
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Mineralocorticoid is to aldosterone as glucocorticoid is to ________.
A) cortisol B) testosterone C) estrogen D) epinephrine |
A) cortisol
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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) blocking the action of growth hormone D) slowing the activity of tissues that require calcium for activity |
B) targeting the bone and activating osteoclasts so that calcium will be released
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The second-messenger mechanism of hormone action operates by ________.
A) synthesizing more of the hormone than is actually needed B) binding to specific receptors and employing the services of G proteins and cAMP C) not responding to a feedback mechanism D) increasing the basal metabolic rate in the target organ |
B) binding to specific receptors and employing the services of G proteins and cAMP
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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 stimulating the pancreas to release insulin C) by decreasing the heart rate, thus decreasing blood pressure D) by increasing blood glucose, fatty acid, and amino acid levels and enhancing blood pressure |
D) by increasing blood glucose, fatty acid, and amino acid levels and enhancing blood pressure
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Aldosterone ________.
A) presence increases potassium concentration in the blood B) is secreted by the neurohypophysis C) functions to increase sodium reabsorption D) production is greatly influenced by ACTH |
C) functions to increase sodium reabsorption
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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) nothingall 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 |
C) the presence of the appropriate receptors on the cells of the target tissue or organ
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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 |
A) first enter into the hypophyseal portal system
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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) strength of the bond between the receptor and hormone C) blood levels of hormone D) type of hormone |
D) type of hormone
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Hemorrhage with a large loss of blood causes ________.
A) no change in blood pressure but a change in respiration B) no change in blood pressure but a slower heart rate C) a lowering of blood pressure due to change in cardiac output D) a rise in blood pressure due to change in cardiac output |
C) a lowering of blood pressure due to change in cardiac output
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The tricuspid valve is closed ________.
A) while the atrium is contracting B) while the ventricle is in diastole C) by the movement of blood from atrium to ventricle D) when the ventricle is in systole |
D) when the ventricle is in systole
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The time of day most hazardous for heart attacks is ________.
A) morning B) noontime C) evening D) during sleep |
A) morning
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During contraction of heart muscle cells ________.
A) the action potential is initiated by voltage-gated slow calcium channels B) calcium is prevented from entering cardiac fibers that have been stimulated C) some calcium enters the cell from the extracellular space and triggers the release of larger amounts of calcium from intracellular stores D) the action potential is prevented from spreading from cell to cell by gap junctions |
C) some calcium enters the cell from the extracellular space and triggers the release of larger amounts of calcium from intracellular stores
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Select the correct statement about the structure of the heart wall.
A) The myocardium is the layer of the heart that actually contracts. B) Connective tissue in the heart wall aids in the conduction of the action potential. C) The heart chambers are lined by the endomysium. D) The fibrous skeleton forms the bulk of the heart. |
A) The myocardium is the layer of the heart that actually contracts.
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The source of blood carried to capillaries in the myocardium would be the ________.
A) coronary veins B) fossa ovalis C) coronary sinus D) coronary arteries |
D) coronary arteries
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Which of the events below does not occur when the semilunar valves are open?
A) AV valves are closed. B) Blood enters pulmonary arteries and the aorta. C) Ventricles are in diastole. D) Ventricles are in systole. |
C) Ventricles are in diastole.
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Norepinephrine acts on the heart by ________.
A) causing threshold to be reached more quickly B) decreasing heart contractility C) blocking the action of calcium D) causing a decrease in stroke volume |
A) causing threshold to be reached more quickly
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Select the correct statement about the function of myocardial cells.
A) Each cardiac muscle cell is innervated by a sympathetic nerve ending so that the nervous system can increase heart rate. B) The influx of potassium ions from extracellular sources is the initiating event in cardiac muscle contraction. C) The refractory period in skeletal muscle is much longer than that in cardiac muscle. D) The entire heart contracts as a unit or it does not contract at all. |
D) The entire heart contracts as a unit or it does not contract at all.
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Damage to the ________ is referred to as heart block.
A) SA node B) AV node C) AV bundle D) AV valves |
B) AV node
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The term for pain associated with deficient blood delivery to the heart that may be caused by the transient spasm of coronary arteries is ________.
A) pericarditis B) ischemia C) angina pectoris D) myocardial infarct |
C) angina pectoris
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The left ventricular wall of the heart is thicker than the right wall in order to ________.
A) pump blood with greater pressure B) pump blood through a smaller valve C) expand the thoracic cage during diastole D) accommodate a greater volume of blood |
A) pump blood with greater pressure
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Blood within the pulmonary veins returns to the ________.
A) left atrium B) right atrium C) right ventricle D) left ventricle |
A) left atrium
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Select the correct statement about cardiac output.
A) A slow heart rate increases end diastolic volume, stroke volume, and force of contraction. B) Decreased venous return will result in increased end diastolic volume. C) Stroke volume increases if end diastolic volume decreases. D) If a semilunar valve were partially obstructed, the end systolic volume in the affected ventricle would be decreased. |
A) A slow heart rate increases end diastolic volume, stroke volume, and force of contraction.
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Normal heart sounds are caused by which of the following events?
A) excitation of the SA node B) closure of the heart valves C) opening and closing of the heart valves D) friction of blood against the chamber walls |
B) closure of the heart valves
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Compared to skeletal muscle, cardiac muscle ________.
A) cells are larger than skeletal muscle cells B) has gap junctions that allow it to act as a functional syncytium C) has more nuclei per cell D) lacks striations |
B) has gap junctions that allow it to act as a functional syncytium
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Which of these vessels receives blood during ventricular systole?
A) pulmonary veins only B) aorta only C) pulmonary arteries only D) both the aorta and pulmonary trunk |
D) both the aorta and pulmonary trunk
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Which vessel of the heart receives blood during right ventricular systole?
A) venae cavae B) pulmonary trunk C) pulmonary veins D) aorta |
B) pulmonary trunk
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Select the correct statement about the heart valves.
A) The AV valves are supported by chordae tendineae so that regurgitation of blood into the atria during ventricular contraction does not occur. B) Aortic and pulmonary valves control the flow of blood into the heart. C) The mitral valve separates the right atrium from the right ventricle. D) The tricuspid valve divides the left atrium from the left ventricle. |
A) The AV valves are supported by chordae tendineae so that regurgitation of blood into the atria during ventricular contraction does not occur.
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If cardiac muscle is deprived of its normal blood supply, damage would primarily result from ________.
A) decreased delivery of oxygen B) an inadequate supply of lactic acid C) a lack of nutrients to feed into metabolic pathways D) a decrease in the number of available mitochondria for energy production |
A) decreased delivery of oxygen
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Which of the following factors does not influence heart rate?
A) gender B) age C) body temperature D) skin color |
D) skin color
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If the length of the absolute refractory period in cardiac muscle cells was the same as it is for skeletal muscle cells ________.
A) it would be much longer before cardiac cells could respond to a second stimulation B) contractions would last as long as the refractory period C) it would be less than 12 ms D) tetanic contractions might occur, which would stop the heart's pumping action |
D) tetanic contractions might occur, which would stop the heart's pumping action
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Which of the following is not part of the conduction system of the heart?
A) AV node B) AV valve C) bundle of His D) SA node |
B) AV valve
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Small muscle masses attached to the chordae tendineae are the ________.
A) papillary muscles B) venae cavae C) pectinate muscles D) trabeculae carneae |
A) papillary muscles
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