HY Questions Flashcards
<p>What ion is primarily responsible for resting membrane potential in neurons and glia?</p>
<p>1. Potassium.</p>
<p>What is the MOA of Baclofen?</p>
<p>1. GABA-B agonist.</p>
<p>What causes the miniature end-plate potential?</p>
<p>1. The spontaneous release of one quanta of ACh.</p>
<p>What is the mechanism of action of tricyclic antidepressants?</p>
<p>1. They block reuptake of NE and 5-HT.</p>
<p>What is responsible for the BBB?</p>
<p>1. Tight junctions between endothelial cells.</p>
<p>Which circumventricular organ has an intact BBB?</p>
<p>1. The subcommissural organ.</p>
<p>What ion is responsible for the initial depolarization of cochlear hair cells?</p>
<p>1. Potassium.</p>
<p>What obstructs the NMDA channel pore at resting membrane potential?</p>
<p>1. Magnesium.</p>
<p>What initiates contraction in smooth muscle?</p>
<p>1. Calcium-calmodulin activation of myosin light chain kinase.</p>
<p>What is the rate limiting enzyme in dopamine synthesis?</p>
<p>1. Tyrosine hydroxlyase.</p>
<p>What is the function of myelin?</p>
<p>1. It increases transmembrane resistance and decreases membrane capacitance.</p>
<p>What drug blocks voltage-gated Na channels?</p>
<p>1. Tetrodotoxin.</p>
<p>What nerve fibers mediate the sensation of sharp pain?</p>
<p>1. A-delta.</p>
<p>What protein mediates fast anterograde axonal transport?</p>
<p>1. Kinesin. </p>
<p>What is the primary target of dentate nucleus efferent fibers?</p>
<p>1. VL nucleus of the thalamus.</p>
<p>What are the most excitatory fibers of the CNS?</p>
<p>1. Climbing fibers.</p>
<p>How do you differentiate a femoral neuropathy from a lumbar plexopathy?</p>
<p>1. Hip adduction will be preserved in the former and absent in the latter.</p>
<p>What is the only output of the cerebellar cortex?</p>
<p>1. The Purkinje cell.</p>
<p>What nerve is compressed in the tarsal tunnel?</p>
<p>1. Posterior tibial nerve.</p>
<p>What structure contains the highest levels of substance P in the brain?</p>
<p>1. The substantia nigra.</p>
<p>What structures are connected by the stria medullary thalami?</p>
<p>1. The septal nuclei and the habenular nuclei.</p>
<p>What cranial nerve contains the nodosal ganglion?</p>
<p>1. The vagus nerve.</p>
<p>Where do SVA fibers synapse in the brainstem?</p>
<p>1. The nucleus of the solitary tract (gustatory nucleus).</p>
<p>Where do the frontopontine fibers travel in the internal capsule?</p>
<p>1. The anterior limb.</p>
<p>What nerve is compressed by Struther's ligament?</p>
<p>1. The median nerve.</p>
<p>Where is the posterior interosseus nerve often entrapted?</p>
<p>1. At the supinator (arcade of Frohse).</p>
<p>Where do GVA fibers traveling in Hering's nerve synapse?</p>
<p>1. The inferior aspect of the solitary tract.</p>
<p>When does the posterior neuropore close?</p>
<p>1. Post-ovulatory day 26.</p>
<p>Where do first-order sympathetic neurons to the pupillary dilator originate?</p>
<p>1. The hypothalamus. </p>
<p>Where is the cortical area for macular vision located?</p>
<p>1. Occipital poles.</p>
<p>Where is the first site of binaural convergence in the auditory pathway?</p>
<p>1. The superior olives.</p>
<p>Where do preganglionic parasympathetic fibers destined for the lacrimal glands synapse?</p>
<p>1. The pterygopalatine ganglion.</p>
<p>What region of primary somesthetic cortex do muscle spindles project?</p>
<p>1. 3a.</p>
<p>What artery perfuses the retrolenticular internal capsule?</p>
<p>1. The anterior choroidal artery. </p>
<p>What is the 5-year stroke risk of asymptomatic 80% carotid artery stenosis?</p>
<p>1. 16.5% (3.3% per year x 5 years).</p>
<p>What gene is responsible for Duchenne muscular dystrophy?</p>
<p>1. Dystrophin (Xp21).</p>
<p>What cranial nerve is most commonly involved in neurosarcoidosis?</p>
<p>1. CN VII.</p>
<p>What is the most common cause of aseptic (viral) meningitis?</p>
<p>1. Enteroviruses.</p>
<p>What lesions result in downbeat nystagmus?</p>
<p>1. Lesions of the cervicomedullary junction.</p>
<p>Maternal hyperglycemia is a risk factor for which spinal developmental disorder?</p>
<p>1. Caudal regression syndrome.</p>