Description : The following are neurotransmitters in the autonomic ganglia: a. GABA b. noradrenaline c. acetylcholine d. 5 HT
Last Answer : acetylcholine
Description : The following are true about the neurotransmitters: a. acetylcholine is inactivated mainly by presynaptic reuptake b. tyrosine is essential for the formation of dopamine c. noradrenaline is inactivated mainly by hydrolysis d. adrenaline is formed from methylation of the noradrenaline
Last Answer : adrenaline is formed from methylation of the noradrenaline
Description : The following enzymes on the left are responsible for the synthesis of the neurotransmitters on the right: a. monoamine oxidase: noradrenaline b. cholinesterase: acetylcholine c. catechol-o-methyl transferase: dopamine d. dopa decarboxylase: adrenaline
Last Answer : dopa decarboxylase: adrenaline
Description : In the autonomic regulation of blood pressure (a) Cardiac output is maintained constant at the expense of other hemodynamic variables (b) Elevation of blood pressure results in elevated ... the sensitivity of the sensory baroreceptor nerve endings might cause an increase in sympathetic discharge
Last Answer : Ans: D
Description : Dantrolene sodium reduces skeletal muscle tone by: A. Reducing acetylcholine release from motor nerve endings B. Suppressing spinal polysynaptic reflexes C. Inhibiting the generation of muscle action potential D. Reducing Ca2+ release from sarcoplasmic reticulum in the muscle fibre
Last Answer : D. Reducing Ca2+ release from sarcoplasmic reticulum in the muscle fibre
Description : The mechanism by which neostigmine improves contraction of myasthenic muscle involves: A. Repetitive binding of the acetylcholine molecules to the same receptors at the muscle endplate B. Diffusion of ... Activation of motor end-plate receptors by neostigmine molecules themselves D. All of the above
Last Answer : D. All of the above
Description : A sympathomimetic amine that acts almost exclusively by releasing noradrenaline from the nerve endings is (a) Ephedrine (b) Dopamine (c) Isoprenaline (d) Tyramine
Description : Tyramine induces release of noradrenaline from adrenergic nerve endings (a) By depolarizing the axonal membrane (b) By mobilizing Ca2+ (c) By a nonexocytotic process (d) Only in the presence of MAO inhibitors
Last Answer : Ans: C
Description : Methyldopa lowers BP by: A. Inhibiting dopa decarboxylase in adrenergic nerve endings B. Generating α-methyl noradrenaline in brain which reduces sympathetic tone C. Generating α-methyl ... as a false transmitter in peripheral adrenergic nerve endings D. Activating vascular dopamine receptors
Last Answer : B. Generating α-methyl noradrenaline in brain which reduces sympathetic tone
Description : Rapid intravenous injection of clonidine causes rise in BP due to: A. Stimulation of vasomotor centre B. Release of noradrenaline from adrenergic nerve endings C. Agonistic action on vascular α2 adrenergic receptors D. Cardiac stimulation
Last Answer : C. Agonistic action on vascular α2 adrenergic receptors
Description : The usual cardiovascular effect of levodopa is: A. Bradycardia due to increased vagal tone B. Rise in blood pressure due to increased noradrenaline content of adrenergic nerve endings C. Fall in blood pressure due to decrease in sympathetic tone D. Both ‘A’ and ‘B’ are correct
Last Answer : C. Fall in blood pressure due to decrease in sympathetic tone
Description : All of the following contribute to the antihypertensive action of propranolol except: A. Direct vasodilatation B. Decreased renin release from kidney C. Adaptation of blood vessels to reduced cardiac output D. Less noradrenaline release from sympathetic nerve endings
Last Answer : A. Direct vasodilatation
Description : A sympathomimetic amine that acts almost exclusively by releasing noradrenaline from the nerve endings is: A. Ephedrine B. Dopamine C. Isoprenaline D. Tyramine
Last Answer : D. Tyramine
Description : Tyramine induces release of noradrenaline from adrenergic nerve endings: A. By depolarizing the axonal membrane B. By mobilizing Ca2+ C. By a nonexocytotic process D. Only in the presence of MAO inhibitors
Last Answer : C. By a nonexocytotic process
Description : The parotid gland: a. contains a fascial sheath which is innervated by second cervical nerve b. receives post-ganglionic parasympathetic nerve from the otic ganglion c. contains a duct which opens ... . is composed of serous acini which contribute to the saliva e. is covered by the massenter
Last Answer : contains a fascial sheath which is innervated by second cervical nerve
Description : True statements about the following neurotransmitters include: a. dopamine is formed from tyrosine b. in the synapse, noradrenaline is inactivated by active reuptake into the presynpatic terminals c. noradrenaline is formed by hydroxylation of dopamine d. all above
Last Answer : all above
Description : Parkinson’s disease (characterized by tremors and progressive rigidity of limbs) is caused by degeneration of brain neurons that are involved in movement control and make use of neurotransmitter (a) acetylcholine (b) norepinephrine (c) dopamine (d) GABA.
Last Answer : c) dopamine
Description : Alzheimer’s disease in humans is associated with the deficiency of (a) glutamic acid (b) acetylcholine (c) gamma aminobutyric acid (GABA) (d) dopamine.
Last Answer : b) acetylcholine
Description : Venlafaxine differs from standard tricyclic antidepressants in that it: A. Does not inhibit 5-HT reuptake B. Does not inhibit noradrenaline reuptake C. Does not have anticholinergic or antiadrenergic property D. Has lower antidepressant efficacy
Last Answer : C. Does not have anticholinergic or antiadrenergic property
Description : Adaptive changes in brain monoamine turnover due to blockade of noradrenaline/5-HT reuptake is credited with the following effect: A. Antipsychotic B. Antianxiety C. Antiparkinsonian D. Antidepressant
Last Answer : D. Antidepressant
Description : The following are true about acetylcholine receptors: a. receptors at all autonomic ganglia are nicotinic b. receptors at the skeletal neuromuscular junction are muscarinic c. ... atropine d. acetylcholine receptors in the neuromuscular junction can be selectively blocked by tubocurarine
Last Answer : acetylcholine receptors in the neuromuscular junction can be selectively blocked by tubocurarine
Description : With regard to the autonomic nervous system: a. the dorsal root ganglia is made up mainly of the cell bodies of the sympathetic nerves b. the preganglionic sympathetic fibres ... the ganglia of both sympathetic and parasympathetic nervous system d. botulin toxin blocks acetylcholine receptors
Last Answer : the dorsal root ganglia is made up mainly of the cell bodies of the sympathetic nerves
Description : The following are true: a. heroin causes miosis by increasing the release of acetylcholine. b. botulinum toxin causes mydriasis by inhibiting the release of acetylcholine c. ... mydriasis by stimulating the alpha receptors d. amphetamine causes mydriasis by inhibiting noradrenaline reuptake
Last Answer : phenylephrine causes mydriasis by stimulating the alpha receptors
Description : The mechanisms involved in the causation of dangerous cardiac arrhythmias due to overdose of tricyclic antidepressants include the following except: A. Intraventricular conduction block B. Potentiation of noradrenaline C. Antagonism of acetylcholine D. Increased vagal tone
Last Answer : D. Increased vagal tone
Description : A person entering an empty room suddenly finds a snake right in front on opening the door. Which one of the following is likely to happen in his neuro- hormonal control system? ... brain. (d) Sympathetic nervous system is activated releasing epinephrine and norepinephrine from adrenal cortex.
Last Answer : (a) Sympathetic nervous system is activated releasing epinephrine and norepinephrine from adrenal medulla.
Description : A person entering an empty room suddenly finds a snake right in front on opening the door. Which one of the following is likely to happen in his neuro-hormonal control system ? (1 ... across the cleft and transmit a nerve impulse (4) Hypothalamus activates the parasympathetic division of brain
Last Answer : (2) Sympathetic nervous system is activated releasing epinephrin and norepinephrin from adrenal medulla
Description : Muscarinic cholinergic receptors (a) Are located only on parasympathetically innervated effector cells (b) Mediate responses by opening an instrinsic Na+ ion channel (c) Are present on vascular endothelium which has no cholinergic nerve supply (d) Predominate in the autonomic ganglia
Description : Muscarinic cholinergic receptors: A. Are located only on parasympathetically innervated effector cells B. Mediate responses by opening an intrinsic Na+ ion channel C. Are present on vascular endothelium which has no cholinergic nerve supply D. Predominate in the autonomic ganglia
Last Answer : C. Are present on vascular endothelium which has no cholinergic nerve supply
Description : What parts of the digestive tract contain nerve endings?
Last Answer : All of them, to my knowledge. Or do you mean specifically sensory ones?
Description : How do signals from nerve endings retain information about their origins as they travel to the brain?
Last Answer : Harp. The answer is in the later part of your question. Each nerve has a dedicated line of transmission from the periphery to the brain. The signals travel fast owing to the fact that ... nerve ultimately signals to a specific part of the brain, which allows you to discriminate various sensations.
Last Answer : I can't determine how much is a lot and how little is already, but believe me, there are a lot of them.
Description : What are the specialized nerve endings at the end of the sensory neurons is called?
Last Answer : Need answer
Description : Which of the following statement(s) is/are true concerning the neuroendocrine responses to shock? a. Sympathetic nerve endings release epinephrine which is responsible for greater than 80% ... injury and sepsis d. The renin-angiotensin axis further augments the sympathetic-mediated vasoconstriction
Last Answer : Answer: c, d The neuroendocrine response to shock attempts to achieve restoration of effective blood volume, mobilization of metabolic substrates, and maintenance of central ... . Angiotensin II is an extremely effective vasoconstrictor that further augments sympathetic-mediated vasoconstriction
Description : Drugs that block the a receptor on effector cells at adrenergic nerve endings (a) Antagonize the effects of isoproterenol on the heart rate (b) Antagonize some of the effects of epinephrine on ... the effects of epinephrine on adenylyl cyclase (d) Cause mydriasis (e) Decreases blood glucose levels
Last Answer : Ans: B
Description : The pain sensation a. arises from stimulation of free nerve endings b. is transmitted to the central nervous system by unmyelinated C fibres c. is transmitted to the brain via the spinothalamic tracts d. all above
Description : The pain sensation a. arises from stimulation of free nerve endings b. is transmitted to the central nervous system by unmyelinated C fibres c. is transmitted to the brain via the ... d. is reduced by local anaesthetics through reduction of the potassium influx into the nerve fibres
Last Answer : is transmitted to the brain via the spinothalamic tracts
Description : Adrenaline is inactive orally because it is: A. Not absorbed from the gastrointestinal tract B. Destroyed by gastric acid C. Completely metabolized in the intestinal mucosa and liver before reaching systemic circulation D. Taken up by adrenergic nerve endings of the intestinal wall, liver and lungs
Last Answer : C. Completely metabolized in the intestinal mucosa and liver before reaching systemic circulation
Description : The α2 adrenoceptors are: A. Located exclusively on the adrenergic nerve endings B. Prejunctional, postjunctional as well as extrajunctional in location C. Selectively activated by phenylephrine D. Selectively blocked by clonidine
Last Answer : B. Prejunctional, postjunctional as well as extrajunctional in location
Description : Initial bradycardia caused by intramuscular injection of atropine is believed to be caused by: A. Stimulation of medullary vagal centre B. Stimulation of vagal ganglia C. Blockade of M2 receptors on SA nodal cells D. Blockade of muscarinic autoreceptors on vagal nerve endings
Last Answer : D. Blockade of muscarinic autoreceptors on vagal nerve endings
Description : The α 2 adrenoceptors are: A. Located exclusively on the adrenergic nerve endings B. Prejunctional, postjunctional as well as extrajunctional in location C. Selectively activated by phenylephrine D. Selectively blocked by clonidine
Description : The following are true about pupil reaction to light: a. secretion of acetylcholine is responsible for pupil dilatation b. constriction of the pupil is mediated by nerve fibres travelling in ... fibres travelling in the long ciliary nerve d. the sympathetic nerve innervates the dilator muscles
Last Answer : the sympathetic nerve innervates the dilator muscles
Description : Myasthenia Gravis is characterized by Options: 1) Decrease in acetylcholine reserve in motor nerve terminal 2) Decrease in dopamine reserve in motor nerve terminal 3) Decrease in receptors for acetylcholine 4) Decrease in dopamine receptors
Last Answer : Correct Answer: 3) Decrease in receptors for acetylcholine
Description : Tetrodotoxin blocks nerve impulse/junctional transmission by: A. Anticholinergic action B. Depleting acetylcholine C. Blocking Na+ channels D. Blocking Ca2+ channels
Last Answer : C. Blocking Na+ channels