Purves Neuroscience Website Questions Ch 6 Answers 3j4v6s

Website Questions Chapter 6: Neurotransmitters and Their Receptors Due October 23, 2013 Name: ___________________________ 1. Which of the following are the physically largest neurotransmitters? a. Biogenic amines b. Amino acid transmitters c. Neuropeptide transmitters d. Purinergic transmitters e. Gaseous transmitters 2. Acetylcholine is used as a neurotransmitter at a. the neuromuscular junction. b. preganglionic synapses of the autonomic (visceral motor) nervous system. c. postganglionic synapses of the sympathetic nervous system. d. widely distributed synapses in the central nervous system. e. All of the above 3. How many subunits does one typically find in the nicotinic acetylcholine receptors? a. Two b. Three c. Five d. Seven e. Nine 4. The banded krait uses which neurotoxin to paralyze its prey? a. Nicotine b. Muscarine c. Conotoxin d. -bungarotoxin e. -tubocurarine 5. Glutamate is a. the most commonly used excitatory neurotransmitter in the brain. b. neurotoxic at high concentrations. c. a nonessential amino acid. d. often synthesized from glial-synthesized glutamine. e. All of the above 6. Which of the following is not a feature of glutamate signaling systems? a. The presence of multiple glutamate receptor families with different ionic selectivities b. Voltage-dependent gating of certain types of glutamate receptor c. The age of large amounts of magnesium by NMDA receptors d. The use of specialized proteins for loading glutamate into vesicles e. The use of specialized proteins for removing glutamate from the synaptic cleft 7. Myasthenia gravis is characterized by a. degeneration of lower motoneurons. b. degeneration of upper motoneurons. c. mutations affecting the synthesis of acetylcholine. d. mutations affecting acetylcholine receptors. e. an autoimmune attack on acetylcholine receptors. 8. Excitotoxicity

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a. can result from very brief (sub-millisecond) increases in glutamate levels. b. can be prevented by istration of glutamate receptor antagonists after a stroke has been diagnosed. c. has not been correlated with the potency of compounds at glutamatergic receptors. d. can occur with some forms of epilepsy and head trauma. e. has been linked to a specific intracellular signaling pathway that activates a family of excitotoxicity genes. 9. Which of the following receptor types can be modulated by both barbiturates and benzodiazepines? a. GABAA b. GABAB c. GABAC d. Glycine e. Muscarinc ACh receptor 10. The presence of which of the following compounds or proteins in a cell makes it highly likely that the cell is a GABAergic neuron? a. Pyridoxal phosphate b. Glutamic acid decarboxylase c. GABA transaminase d. -hydroxybutyrate e. Glutamine 11. The transmitter GABA excites immature cortical neurons because a. immature GABA receptors more sodium than chloride. b. immature GABA-receptive neurons have a more negative firing threshold than mature neurons do. c. immature GABA-receptive neurons express many Na +/K+/Cl– cotransporters. d. immature GABA-receptive neurons express many K+/Cl– cotransporters. e. the opening of GABA receptor channels tends to excite immature cortical networks because of the networks’ wiring. 12. Which of the following is not a catecholamine? a. Dopamine b. Histamine c. Norepinephrine d. Epinephrine e. All of the above are catecholamines. 13. Listed below are the enzymes needed to synthesize epinephrine (adrenaline). 1. Dopamine -hydroxylase 2. Tyrosine hydroxylase 3. Phenylethanolamine-N-methyl transferase 4. DOPA decarboxylase Which of the following is the correct sequence of enzyme actions in the synthesis of epinephrine? a. 2 ;4 ;1 ;3 b. 3 ;1 ;4 ;2 c. 2 ;1 ;3 ;4 d. 1 ;2 ;4 ;3 e. 2 ;4 ;3 ;1 14. Serotonin reuptake blockers such as fluoxetine are used clinically a. to treat hypertension. b. to treat panic disorders. c. as antidepressants. d. as antipsychotics.

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e. to treat generalized anxiety. 15. Cocaine acts a. on GABAA receptors. b. as an MAO inhibitor. c. by blocking serotonin reuptake. d. by blocking dopamine reuptake. e. by blocking biogenic amine vesicular transporters. 16. While the nature of adenosine’s actions on central circuits is not well understood, adenosine is thought to have an inhibitory or relaxing effect because of which of the following observations? a. Its presence in many inhibitory neurons b. Its ability to block the reuptake of inhibitory transmitters c. Its actions as a cofactor at glycine receptors d. The consequences of xanthine blockade of adenosine receptors e. The co-localization of adenosine with GABA in GABAergic synaptic vesicles 17. Peptide neurotransmitters are often released a. shortly after their synthesis in presynaptic terminals. b. as pre-propeptides. c. as propeptides. d. more readily and quickly than nonpeptide transmitters. e. together with nonpeptide transmitters. 18. Which of the following is not a class of opiod peptides? a. Dynorphins b. Endorphins c. Enkephalins d. Endocannabinoids e. All of the above are opiod peptides. 19. Listed below are the five steps in a nitric oxide (NO)–mediated signaling event. 1. Calcium binds to calmodulin 2. Activation of nitric oxide synthase 3. NO diffusion for tens of micrometers 4. Activation of guanylyl cyclase 5. Inactivation by reaction with oxygen Which of the following is the correct sequence of these steps? a. 1 ;2 ;3 ;4 ;5 b. 5 ;4 ;3 ;2 ;1 c. 4 ;2 ;3 ;1 ;5 d. 2 ;3 ;4 ;1 ;5 e. 1 ;5 ;2 ;3 ;4 20. Based upon the distribution of endocannabinoid receptors in the brain, it can be surmised that these compounds have a likely influence on a. neocortex. b. the hippocampus. c. basal ganglia. d. the hypothalamus. e. All of the above

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Extra credit (5 pts): Find a disease, not mentioned in the textbook, that involves one of the neurotransmitters, their synthesizing enzymes or receptors in Chapter 6. Provide (A) the name of the disease, (B) the molecule affected (i.e., mutated, missing, etc), (C) 1-2 sentences on the disease mechanism (e.g. does a mutation of X imply no production of transmitter y, or does a mutation of Z imply no function receptor), (D) the source of your information – journal article, website, etc.

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