Autonomic Nervous System MCQ Answers PDF

# Autonomic Nervous System ## Concerning the autonomic nervous system: - Supplies voluntary organs - Is an efferent two neurons system - Is an efferent one neuron system - Is part of somatic nervous system ## The autonomic nervous system, all are true except: - Contains preganglionic neurons....

# Autonomic Nervous System ## Concerning the autonomic nervous system: - Supplies voluntary organs - Is an efferent two neurons system - Is an efferent one neuron system - Is part of somatic nervous system ## The autonomic nervous system, all are true except: - Contains preganglionic neurons. - Has a sympathetic subdivision. - Innervates skeletal muscles. - Has a parasympathetic subdivision. ## Effector organs of the ANS include all of the following EXCEPT: - Arteriolar smooth muscle. - Heart. - Visceral smooth muscles. - Skeletal muscles ## Regarding the autonomic nervous system - The sympathetic system is catabolic - Parasympathetic acts as one unit in stresses - Sympathetic system arises from some cranial nerves and few sacral segments - Sympathetic ganglia are terminal ## Autonomic Ganglia are characterized by all of following except: - They act as distributing center - They are a group of cell bodies of neurons outside the CNS - Paravertebral ganglia are the site of relay of parasympathetic fibers - Terminal ganglia are the site of relay of parasympathetic fibers ## The autonomic ganglia: - Are the sites of relay of afferent neurons. - Function as distributing centres. - Are located inside the CNS. - Are relay stations for all preganglionic fibers passing through them ## Regarding autonomic ganglia: - Terminal ganglia are modified sympathetic ganglia - Collateral ganglia are only parasympathetic ganglia - Adrenal medulla is supplied by preganglionic adrenergic fibers - Terminal ganglia can be present in the viscera ## The sympathetic preganglionic nerve fibres: - Arise from the cervical segments of the spinal cord. - Originate at the autonomic ganglia. - Are myelinated nerve fibres belonging to the B group - Those supply the abdominal viscera relay in the sympathetic chain ## Sympathetic stimulation produces: - Increase in motility of the stomach - Constriction of pupils - Dilatation of cutaneous blood vessels - Increase in blood glucose level ## The sympathetic response in a "fight or flight" reaction causes a decrease in the: - Arterial blood pressure - Diameter of the pupil - Resistance of the airway - Blood glucose ## Stimulation of the cervical sympathetic division causes - Contraction of Pupil dilator muscle - Vasodilation of skin blood vessels - Trophic salivary secretion - a and c are correct ## Sympathetic nerve activity - Prepares human body to stressful conditions - Always causes contraction of smooth muscles - Causes relaxation of dilator muscles of the eye to dilate pupils - Relaxes smooth muscles of intestinal wall and sphincters ## Regarding the Greater splanchnic nerve, all are true EXCEPT: - Is formed of Postganglionic fibers - Is formed of preganglionic fibers arising from lower 6 thoracic segments - Carries sympathetic fibers which cause contraction of splenic capsule - Supplies abdominal organs causing contraction of pyloric sphincter ## The greater splanchnic nerve: - Belongs to sympathetic system - Increases contraction of wall of gastrointestinal tract and inhibits its sphincters - Decreases glycogenolysis and fibrinogen formation from the liver - Produces dilatation of bronchi ## In Horner's syndrome, all correct, except: - The upper eye lid is elevated - The skin is dry and red - Miosis - Enophthalmos ## Dropping of the eyelid (ptosis) is caused by damage to : - The third cranial nerve. - The parasympathetic supply to the eye. - The sympathetic supply to the eye. - Lesion in lumbar 2,3. ## A lesion in the cervical sympathetic Chain (Horner's syndrome) causes: - Increased sweating. - Drooping of the upper eyelid (= ptosis). - Mydriasis (= dilatation of the pupil). - Inhibition of salivary glands secretion. ## Stimulation of sympathetic supply to the lung causes allexcept: - Inhibition of bronchial secretion - Bronchoconstriction - Pulmonary vasoconstriction - Better ventilation ## Sympathetic supply to abdominal viscera: - Start from the lateral horn cells of the lower six thoracic segments - Cause evacuation of the gall bladder - Micturition - Lowers the blood glucose level through stimulating glycogenesis ## Stimulation of lesser splanchnic nerve produces - Male erection - Contraction of internal anal and urethral sphincters - Contraction of splenic capsule - Increased glucose release by liver ## The sympathetic nervous system has all of the following characters except: - It is mostly noradrenergic. - It is of little importance in visual accommodation. - It antagonizes mostly parasympathetic functions. - It is anabolic. ## Stimulation of the sympathetic N.S. causes: - Contraction of the ciliary muscle for near vision. - Mostly generalized actions affecting many systems. - Decreased glycogenolysis & lipolysis. - Increased gastric HCl & pepsin secretion. ## All the following statements are correct except: - Stimulation of the greater splanchnic nerve causes adrenomedullary secretion. - Acetylcholine is normally present at low concentrations in the blood. - Dilator pupillae muscle contains a-receptor while cardiac muscle contains ẞ-receptor - Stimulation of the Postganglionic Nerve fibres arising from the collateral ganglia cause secretion from the adrenal medulla. ## Sympathetic activity is characterized by the following except: - Contraction of the radial muscle in the iris. - A raised blood level of catcholamines. - Constriction of blood vessels in the skin. - A fall in the blood glucose level. ## All the following statements are true except: - Accommodation to near vision is mediated by increased acetylcholine. - Vagotomy may cause the heart rate to increase significantly. - Arteriolar VC at rest may be due to the basal secretion of catecholamines from the adrenal medulla - Noradrenaline is not secreted by the adrenal medulla. ## Parasympathetic stimulation results in - Decreased salivary secretion - Increased intestinal secretion and motility - Increased blood glucose level - Bronchodilatation ## Stimulation of the vagus nerve produces - Contraction of the spleen - Decrease the ventricular contraction - Decrease the heart rate - Dilatation of the bronchioles ## Parasympathetic division of the autonomic nervous system - Arises only from sacral segments number 2,3,4 - Is anabolic in function - a and b are correct - None of the above ## Parasympathetic nerve activity - Is essential for survival - Affects only smooth muscles and glands - Causes contraction of dilator pupillae muscles to allow accommodation for near vision - Contracts smooth muscles of intestinal wall and relaxes sphincters ## One of the following is not supplied by parasympathetic fibers: - Atria - Ventricles - Gall bladder - Salivary glands ## Preganglionic fibers in the facial nerve: - Arise from inferior salivary nucleus - Causes trophic salivary secretion. - Supply the motor fibers to the ciliary muscles - Relay in submandibular ganglion ## Stimulation of the occulomotor nerve causes: - Contraction of the dilator pupillae muscles - Contraction of the ciliary muscles - Contraction of pilo-erector muscles - Secretion of the gastric glands ## Stimulation of the vagus nerve produces: - True salivary secretion - Bronchoconstriction - Pupillary constriction - Contraction of urinary bladder wall ## The sacral division of the autonomic nervous system: - Belongs to the sympathetic system - Its stimulation can produce erection of penis - Supplies abdominal viscera - Inhibits defecation ## Stimulation of pelvic nerve may lead to - Decrease heart rate - Relaxation of smooth muscles of bronchi and bronchioles - Ejaculation of semen - Micturition ## Stimulation of the facial nerve produces - Contraction of pupil constrictor muscle - Decrease the lacrimal secretion - Increase the secretion of sweat glands - Increase the secretion of watery saliva ## Stimulation of glossopharyngeal nerve may lead to - Decrease heart rate - Increase the parotid gland secretion - Increase the nasolacrimal - Micturition ## The parasympathetic supply to the head causes: - Contraction of the dilator pupillae muscles - Increase power of the lens, thus allowing near vision - Inhibit the secretion of salivary glands. - None of the above ## Stimulation of parasympathetic neurons leads to an increase of: - GIT motility - Heart rate - Blood pressure - Sweating ## Stimulation of the vagus nerve leads to: - Bronchodilatation - Pupil dilation - Bronchoconstriction - Inhibition of insulin secretion ## Vagus nerve stimulation causes the following except: - Inhibits wall of ventricle - Produces constriction of bronchi - Can be inhibited by atropine - Increases gastric secretion ## An injury to the first 4 sacral segments of the spinal cord produces: - V.D. in the Cutaneous blood vessels. - Disturbance of sweat secretion. - Lack of erection of the penis in males & clitoris in females. - Relaxation of the internal anal & urethral sphincters. ## About the vagus nerve, all the following is true except: - It contains parasympathetic preganglionic Fibres. - It has no direct effect on ventricular contraction. - It causes increased peristaltic movements of the intestinal wall. - It produces micturition. ## Parasympathetic tone is mostly responsible for: - Decreasing the blood flow to the gut (GIT or alimentary canal). - Keeping the fasting blood glucose level constant. - Maintaining resting heart rate within normal. - Causing bronchodilatation. ## Regarding the pelvic nerve, the following is true Except : - It is the nerve of erection - It is motor to the urinary bladder & distal half of the large intestine. - It is inhibitory to both the internal anal & urethral sphincters. - It is formed of preganglionic & postganglionic nerve fibres. ## The parasympathetic nerves: - Are important in emergency conditions e.g. fight & flight reactions. - Play important functions in skin and skeletal muscles. - Tend to have longer postganglionic fibers than preganglionic Fibres. - Mostly exert effects opposite to those done by the sympathetic Nerves ## Parasympathetic postganglionic cholinergic fibres innervate all the following except: - Salivary glands - Lacrimal glands - Sweat glands - Exocrine cells of pancreas ## Parasympathetic preganglionic neurons: - Are much shorter than the postganglionic neurons - Are more numerous than the postganglionic neurons - Secrete the same transmitter as the postganglionic neurons - Originate from all the sacral segments of the spinal cord ## Parasympathetic neurons are inhibitory to smooth muscles in: - The ciliary muscle - Dilator pupillae muscle - The bronchial tree - Mucosal blood vessels ## Parasympathetic innervation is antagonistic to sympathetic innervation on: - Constrictor pupillae muscle - Cutaneous blood vessels - Salivary glands secretion - The act of micturition ## The functions of parasympathetic Innervation to the salivary glands is: - V.C. & secretion. - V.D. & secretion - V.D. & inhibition of secretion. - Secretion of scanty viscous saliva. ## Which of the following may be produced by parasympathetic Stimulation: - Acceleration of the heart. - Contraction of the urinary bladder wall. - V.D. of skeletal muscle blood vessels. - Dilatation of the pupil. ## The efferent impulses that stimulate salivary secretion proceed along all the following nerves except the: - Chorda tympani. - Sympathetic nerves. - Occulomotor nerve. - Glossopharyngeal nerve. ## The parasympathetic nervous system affects all EXCEPT: - Heart. - Pupillary smooth muscles. - Salivary glands. - Adrenal glands. ## Which of the following structures is an example where double innervation does not apply? - The heart. - The bladder. - The intestines - Splenic capsule. ## Parasympathetic nerves: - Have same effects to those of sympathetic nerves when both supply the same organ - Play an important part in vasodilatation in skeletal muscle during prolonged exercise - Liberate acetylcholine at both preganglionic and postganglionic endings. - Tend to have longer postganglionic than preganglionic fibres. ## The vagus nerve: - When stimulated has little direct effect on the strength of ventricular contraction. - Contains afferent nerve fibres only. - Exerts at rest a tonic effect on the heart which becomes more marked with regular long distance running. - Contains parasympathetic postganglionic fibers. ## Which of the following is a feature of the sympathetic, but not the parasympathetic nervous system? - Short preganglionic neurons - Preganglionic neurons release norepinephrine - Preganglionic neurons release acetylcholine (ACh) - Preganglionic neurons relay in autonomic ganglia ## Regarding Acetyl choline, all are correct EXCEPT: - Is formed in autonomic nerve endings - Is secreted in all autonomic ganglia & all postganglionic autonomic fibers - Is inactivated by acetylcholine esterase enzyme at nerve endings - Is inactivated by pseudo-choline esterase enzyme in blood ## Acetylcholine is a neurotransmitter at: - sweat glands - parasympathetic ganglia - the neuromuscular junction - all of the above ## Cholinergic fibers: - Release acetylcholine at their terminals - Belong to pre- and post- ganglionic parasympathetic system - Supply the adrenal medulla - All of the above ## Noradrenaline: - Is formed only in sympathetic nerve endings - Is removed mainly by active reuptake into target cells - Is inactivated by COMT enzyme at nerve endings & tissues - Is inactivated by MAO enzymeat nerve endings ## Adrenergic fibers: - Release adrenaline at their terminals - Belong to parasympathetic system - Are thin myelinated B-fibers - Represent the postganglionic sympathetic fibers & release noradrenaline ## Presynaptic adrenergic receptors: - Are present on postganglionic parasympathetic fibers - Are present on postganglionic sympathetic fibers - Are present on preganglionic parasympathetic fibers - Are present on preganglionic parasympathetic fibers ## Autonomic transmission - Preganglionic sympathetic depend on muscarinic cholinergic transmission - Preganglionic parasympathetic depend on muscarinic cholinergic transmission - Postganglionic sympathetic depend on muscarinic cholinergic transmission - Postganglionic parasympathetic depend on muscarinic cholinergic transmission ## B- adrenoreceptor, when activated, it will: - Increase cardiac contractility - Increase the contractility of splenic capsule - Cause vasoconstriction of skin blood vessels - Cause bronchoconstriction ## Adrenergic receptors are classified into: - a receptors which cause inhibition of adenyl cyclase - ẞ1-receptors which increase the cardiac properties through increased CAMP - a2- receptors which increase intracellular calcium ions - ẞ2 receptors which cause contraction of the bronchial muscles ## Receptors at organ supplied by postganglionic parasympathetic: - Alpha adrenergic - Muscarinic - Nicotinic - Beta adrenergic ## Acetylcholine is secreted by all the following, except; - All preganglionic autonomic fibers - All postganglionic parasympathetic fibers - Postganglionic sympathetic fibers supply sweat glands - Postganglionic sympathetic fibers that supply skeletal blood vessels and produce VC ## About the chemical transmission in the sympathetic N.S: - Noradrenaline is released by both preganglionic & postganglionic Sympathetic fibers - Noradrenaline acts mainly on the ẞ-adrenergic receptors. - Noradrenaline contributes to 80% of the secretion of the suprarenal medullae - The a-adrenergic stimulators case contraction of the plain muscles in the seminal vesicles & vas deferens. ## All the following about acetylcholine is correct except: - It causes slowing of the heart rate. - It is released by the parasympathetic Nerve endings in the sweat glands. - It is the neurotransmitter in the suprarenal medullae. - It is not affected by the enzyme COMT. ## The acetylcholine is secreted by the following neurons except: - All preganglionic nerve endings. - The sympathetic Postganglionic Supply to the blood vessels in skeletal muscles. - The parasympathetic Postganglionic Supply to the heart. - The sympathetic Postganglionic Supply to the heart ## Which of following responses is mediated by parasympathetic muscarinic receptors? - Dilation of bronchiolar smooth muscle - Miosis - Ejaculation - Increased cardiac contractility ## Neurotransmitter of preganglionic sympathetic nerve fiber is: - Noradrenaline - Adrenaline - ACh - None of the above is correct ## Catecholamines can be removed from the tissues by all except - Active re-uptake by the sympathetic nerve endings - Oxidation by mono-amine oxidase enzymes - Methylated by O-rnethyl transferase enzyme - Hydrolyzed by cholineacetylase enzyme ## Which of the following is adrenergic fibers: - Most postganglionic sympathetic fibers - Preganglionic sympathetic fibers - Preganglionic fiber to adrenal medulla - Preganglionic parasympathetic fibers ## The stimulation of (a) adrenergic receptors results in: - Increase heart rate - Bronchodilatation - Glycogenolysis - Vasoconstriction ## Adrenergic receptors are classified into: - a receptors which cause decrease in cAMP - a2 receptors which increase intracellular calcium ions - a receptors which increase the cardiac properties - ẞ2 receptors which cause relaxation ofbronchial muscles ## Which autonomic receptor mediates an increase in heart rate? - Adrenergic al receptors - Adrenergic ẞ1 receptors - Adrenergic ẞ2 receptors - Cholinergic muscarinic receptors ## Which receptor mediates slowing of the heart? - al Receptors - ẞ1 Receptors - ẞ2 Receptors - Muscarinic receptors ## Adrenal medulla: - Receives preganglionic parasympathetic fibers - Secretes 80% norepinephrine and 20% epinephrine - Is stimulated by acetylcholine. - Is a modified parasympathetic ganglia ## The adrenal medulla: - Secretes mainly during rest and sleep - 80% of its secretion is noradrenaline - Augments the sympathetic effects - Receives postganglionic cholinergic fibers ## Concerning the adrenal medulla, all the following is true except: - Its secretion is increased in emergency conditions. - It secrets epinephrine 80% & norepinephrine 20%. - It augments and prolongs the effects of sympathetic stimulation. - It receives preganglionic nerve supply from the anterior horn cells of the lower 6 thoracic segments of spinal cord. ## Which autonomic receptor mediates secretion of epinephrine by the adrenal medulla? - Adrenergic al receptors. - Adrenergic ẞ1 receptors - Cholinergic muscarinic receptors - Cholinergic nicotinic receptors ## Atropine, a parasympatholytic drug, will cause all of the following EXCEPT: - Pupil dilatation - Increase sweat secretion - Decrease salivary secretion - Decrease intestinal contraction and secretion ## Propranolol, a B-adrenergic blocker drug will cause: - Increase the heart rate - Increase the blood glucose - Bronchoconstriction - Increase the arterial blood pressure ## Eserine/physostigmine, a parasympathomimetic drug with anti-esterase activity: - Increase the cardiac contraction - Increase the sweat secretion - Inhibit the contractility of intestinal wall - Increase the blood glucose level ## Which autonomic receptor is blocked by hexamethonium at the ganglia, but not at the neuromuscular junction? - Adrenergic al receptors - Adrenergic ẞ1 receptors - Cholinergic muscarinic receptors - Cholinergic nicotinic receptors ## Patients are enrolled in trials of a new atropine analogue (parasympatholytic drug). Which of the following would be expected? - Increased AV node conduction velocity - Pupillary constriction - Sustained erection - Increased sweating ## Propranolol, a beta blocker, has which of the following effects? - Decreases heart rate - Increases stroke volume - Decreases splanchnic vascular resistance - Decreases cutaneous vascular resistance ## Albuterol is useful in the treatment of asthma because it acts as an agonist at which of the following receptors? - al Receptor - ẞ1 Receptor - ẞ2 Receptor - Muscarinic receptor ## Atropine causes dry mouth by inhibiting which of the following receptors? - al Receptor - ẞ1 Receptor - ẞ2 Receptor - Muscarinic receptor ## It is true to say that nicotine in small dose has an excitatory influence on the: - Receptors located in the neurons present in the sympathetic ganglia. - Beta adrenergic receptors. - Alpha adrenergic receptors. - Receptors those are normally responsive to postganglionic Parasympathetic fibres. ## Nicotine in small doses stimulates the: - Alpha adrenergic receptors. - Receptors at the parasympathetic postganglionic nerve fibres. - Receptors in the neurons present in the sympathetic chain - Beta adrenergic receptors. ## An injection of atropine causes all the following effects except: - An increase in the heart rate. - Pupillo-dilatation. - Difficult micturition. - Constriction of the bronchi. ## A drugs which blocks beta adrenoceptors is likely to cause: - Relaxation of sphincters in the alimentary tract. - Dilatation of the bronchi. - A decrease in the force of myocardial contraction in someone with heart failure. - A decreased dilatation by the blood vessels of skeletal muscles in response to circulating adrenaline. ## Which of the following drugs would not increase sympathetic activity? - Norepinephrine. - Phenylephrine. - Pilocarpine. - Epinephrine ## Injection of atropine is liable to cause: - Constipation. - Diarrhoea. - Bronchial constriction. - Bradycardia. ## About the drugs that affect the autonomic N.S., all following is true except: - Atropine injection causes relaxation of the skeletal muscles. - Epinephrine injection helps in the treatment of bronchial asthma. - Acetylcholine injection stimulates the autonomic ganglia. - In the body, epinephrine is formed only in the adrenal medulla & C.N.S. ## A drug that blocks the alpha adrenergic receptors is likely to cause: - A reduction in sweat production. - A fall in the arterial B.P. due to slowing of the heart. - Failure of mydriasis in emotions. - Constriction of the bronchi. ## A drug which blocks the beta adrenergic receptors causes: - Dilatation of the bronchial muscle. - Relaxation of the sphincters in the alimentary canal. - Inhibition of cardiac properties. - Dilatation of the visceral blood vessels. ## The alpha adrenergic receptors: - Are not stimulated by epinephrine. - When stimulated, they reduce the gastrointestinal (GI) motility. - When stimulated, they accelerate the heart. - When stimulated, they decrease the tone of the GI sphincters. ## Epinephrine produces all the following effects except : - Bronchoconstriction. - Coronary V.D. - Glycogenolysis. - Increased cardiac properties. ## A drug that blocks the beta adrenergic receptors in likely to cause: - Relaxation of the sphincters of the GIT. - An increase in the cardiac properties. - Increased glycogenolysis & lipolysis in response to epinephrine. - Bronchoconstriction. - Excessive V.D. in skeletal muscles in response to epinephrine. ## Stimulation of the alpha adrenergic receptors produces: - Increase gastrointestinal motility. - Bronchodilatation. - Enhanced glycogenolysis & lipolysis. - Relaxation of the sphincters in the alimentary canal. - Contraction of the spleen capsule. ## The characters of adrenaline include: - It is the chemical transmitter at the adrenergic postgans. Symp. Nerve endings. - It has a greater vasoconstrictor effect than noradrenaline. - It is hydrolyzed by the phosphodiestraseenzyme. - It has a greater effect upon cardiac muscle than noradrenaline. ## Noradrenaline (norepinephrine): - Is liberated by the symp. Pergang. Fibers that supply the adrenal medulla . - Is released by the symp. Postgang. Neurons that supply the adrenal medulla. - Acts mainly on the alpha adrenergic receptors. - Is secreted with adrenaline from the adrenal medulla at an equal rate. - Is blocked by the choline esterase enzyme. ## The alpha adrenergic receptors mediate all the following effects except: - Vasoconstriction. - Spleen contraction. - Relaxation of the intestinal wall. - Increased cardiac activity. ## A physiological action of epinephrine produced by contact with the beta adrenergic receptors is; - V.C. in skeletal muscles. - Dilatation of the pupil. - Contraction of the pilo-erector muscles. - Increased strength of myocardial contraction. ## Inhibitors of choline esterase enzymes: - Enhance the effects of parasympathetic stimulation - Inhibit the effect of parasympathetic stimulation - Inhibit acetylcholine release by cholinergic nerve terminals - Block the action of acetylcholine in autonomic ganglia ## An abnormally high level of acetylcholine in tissues all over the body is due to: - Exposure to stress - Widespread physiological activation of the parasympathetic nervous system - Increased activity of muscarinic receptors - Decreased activity of cholinesterase enzyme ## Administration of a muscarinic receptor antagonist leads to: - Increased sweat secretion - Decreased sweat secretion - Increased gastric motility - Bronchoconstriction ## Which of the following visceral tissues receives sympathetic postganglionic neurons only? - Adrenal medulla - Sweat glands - Anal sphincters - The iris # Autonomic Nervous System | # | Answer| # | Answer| # | Answer| # | Answer| # | Answer| |---|---|---|---|---|---|---|---|---|---| |1| B|26| B| 51| B| 76|A|101| C| |2| C|27| C| 52| B| 77| D| 102 | B| |3| D|28| B| 53| C| 78| D| 103 |A| |4| A|29| D| 54| D| 79| B| 104 | D| |5| C|30 | B| 55| D| 80| D| 105 | E| |6| B|31| D| 56| C| 81| C| 106 | D| |7| D|32| B| 57| C| 82| C| 107| C| |8| C|33| B| 58| A| 83| D| 108| D| |9| D|34 | B| 59| B| 84| D| 109| D| |10| C|35| D| 60| D| 85|B| 110| A| |11| D|36| D| 61| D| 86| C| 111| D| |12| A|37| B| 62| D| 87| B| 112| B| |13| A|38| B| 63| D| 88| D| 113| B| |14| A|39| A| 64| B| 89| A| |15| A|40| C| 65| D| 90| A| |16| C|41| A| 66| A| 91| C| |17| B|42| C| 67| B| 92| D| |18| B|43| D| 68| B| 93| A| |19| A|44| C| 69| D| 94| C| |20| B|45| D| 70| D| 95| D| |21| D|46| D| 71| B| 96| C| |22| B|47| C| 72| D| 97| C| |23| D|48| C| 73| B| 98| A| |24| D|49| D| 74| C| 99| A| |25| D|50| D| 75| D| 100| C|