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Question 1
Incorrect
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Which one of the following nerve fibers is involved in proprioception?
Your Answer: A β fiber
Correct Answer: An α fiber
Explanation:Proprioception, also known as kinaesthesia, is the sense through which humans perceive their own position and movements. α nerve fibers are specifically involved in transmitting proprioception stimuli.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 2
Incorrect
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Which of the following associations is false?
Your Answer: Facial nerve – stylomastoid foramen
Correct Answer: Mandibular nerve – foramen lacerum
Explanation:– The olfactory nerves pass through the cribriform plate- The maxillary division of the trigeminal nerve passes through the foramen rotundum- The facial nerve passes through the stylomastoid foramen- The mandibular division of the trigeminal nerve pass through the foramen ovale- The glossopharyngeal nerve passes through the jugular foramen.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 3
Incorrect
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Which part of the neuron has the highest concentration of sodium channels per square millimetre of the cell membrane?
Your Answer: Initial segment 350-500
Correct Answer: Nodes of Ranvier
Explanation:The nodes of Ranvier contain Na+/K+ ATPases, Na+/Ca2+ exchangers and a high density of Na+ channels. The estimated concentration of sodium channels in the node is of ∼1500/μm2.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 4
Correct
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The main reason for the prolonged effect of the withdrawal reflex is:
Your Answer: Multiple connections between afferent and efferent neurons
Explanation:The withdrawal reflex is a spinal reflex that protects the body from harmful stimuli. Spinal reflexes are mostly monosynaptic and are mediated by a simple reflex arc. Withdrawal reflex is mediated by a polysynaptic reflex resulting in stimulation of many motor neurons in order to establish a quick and prolonged response.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 5
Correct
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The superior orbital fissure is the site of entry/exit for which of the following group of nerves?
Your Answer: CN III, IV, V1, VI
Explanation:The superior and inferior divisions of oculomotor nerve (III), trochlear nerve (IV), lacrimal, frontal and nasociliary branches of ophthalmic V1 and the abducens nerve (VI)
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This question is part of the following fields:
- Medicine
- Neurology
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Question 6
Correct
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Which afferent information is carried by the dorsal column?
Your Answer: Proprioception/ discriminative touch
Explanation:The posterior grey column (dorsal column) is responsible for carrying the sensation of proprioception, two-point discrimination, and vibration to the nucleus proprius, situated anterior to the substantia gelatinosa throughout the spinal cord.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 7
Correct
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Question 8
Correct
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Regarding the innervation of cerebral blood vessels, which of the following triggers a vasoconstrictor effect?
Your Answer: Neuropeptide-Y
Explanation:Substance P is a potent vasodilator, VIP or vasoactive intestinal peptide has vasodilator properties in the intestines. PHM 27 is a potent calcitonin receptor agonist; endogenous analogue of human VIP. CGRP or Calcitonin Gene-Related Peptide is a vasodilator which is found to play an important role in migraines. Neuropeptide Y is a strong vasoconstrictor.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 9
Incorrect
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Neurogenesis occurs throughout life in the following two areas:
Your Answer: Olfactory nerve and amygdala
Correct Answer: Hippocampus and striatum
Explanation:In humans, neurogenesis or new neurons are continually born during adulthood in two regions of the brain: The subgranular zone (SGZ), part of the dentate gyrus of the hippocampus and the striatum. In other species of mammals, adult-born neurons also appear in the olfactory bulb. In humans, however, few if any olfactory bulb neurons are generated after birth.
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This question is part of the following fields:
- Medicine
- Neurology
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Question 10
Correct
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What happens first during depolarisation of the membrane potential?
Your Answer: Gated Na channels open allowing the influx of Na
Explanation:Generation of an action potential in response to a stimulus is a result of a previously maintained resting membrane potential (RMP). Generation of resting membrane potential is mediated mainly by potassium ions. Several membrane proteins maintain RMP by transport of ions in and out of cell. Na+/K+ ATPase pump maintains a concentration gradient of Na+ and K+ ions. Na+ concentration in extracellular fluid is higher compared to intracellular fluid and K+ ion concentration is higher intracellularly. Generation of an action potential facilitates opening of Na+ ion channels which allow for Na+ to diffuse inside the cell according to the concentration gradient.
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This question is part of the following fields:
- Medicine
- Neurology
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SESSION STATS - PERFORMANCE PER SPECIALTY
