Category: Anatomy

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16. GABAergic cells of the cerebellum

  1. Purkinje cells, one of the largest neurons in the brain, exert inhibitory effects on their targets and use GABA as their neurotransmitter?
  2.  Cerebellar Golgi cells are located in the granular layer of the cerebellum and they use GABA as their neurotransmitter?
  3. Cerebellar stellate cells are inhibitory interneurons located in the  molecular layer of the cerebellum and they use GABA as their neurotransmitter?
  4. Unipolar brush cells (UBCs) are a class of inhibitory  interneurons found in the granular layer of the cerebellar cortex which use GABA as their neurotransmitter?
  5. Cerebellar basket cells synapse on the cell bodies of Purkinje cells, exert inhibitory effect on them, and use GABA as their neurotransmitter?
  6. Cerebellar granule cells are the most numerous neurons in the brain, they use glutamate as their neurotransmitter  and  exert excitatory effects on their targets?

  1. T
  2. T
  3. T
  4. F
  5. T
  6. T

  1. Unipolar brush cells (UBCs) are excitatory glutamatergic interneurons. They can be found the granular layer of the cerebellar cortex but also in the cochlear nucleus in the brainstem.

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15. The deep cerebellar nuclei

  1. Receive glutamatergic inputs from Purkinje’s cells. (T/F?)
  2. Most of the output fibers of the cerebellum originate from the deep cerebellar nuclei, with the exception of the fibers from the flocculonodular lobe, witch synapse directly with the inferior olivary nucleus (ION). (T/F?)
  3. The dentate nuclei are situated deep within the lateral hemispheres of the cerebellum and receive most of their connections from the lateral hemispheres  of the cerebellum. (T/F?)
  4. The dentate nucleus can be divided into dorsal (motor) and ventral (nonmotor) domains. (T/F?)
  5. The interposed nucleus is composed of globose nucleus and emboliform nucleus and is located in the vermis. (T/F?)
  6. Fastigial nuclei are paired structures located in vermis. (T/F?)

  1. F
  2. F
  3. T
  4. T
  5. F
  6. T

  1. The deep cerebellar nuclei receive GABAergic (inhibitory) inputs from Purkinje’s cells.
  2. The fibers from the flocculonodular lobe synapse directly with the vestibular nuclei.
  1. The interposed nucleus is located in the paravermal (intermediate) zone.

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14. Anatomy of the cerebellum

  1. It has about 10% of the total brain volume. (T/F?)
  2. It has about 3.6 times less neurons than there is in the neocortex. (T/F?)
  3. Two cerebellar peduncles connect cerebellum with the rest of the brain. (T/F?)
  4. The cerebrocerebellum, or neocerebellum receives input exclusively from the cerebral cortex via the pontine nuclei. (T/F?)
  5. Two of the deep cerebellar nuclei, the dentate and the emboliform are fused and form a single, interposed nucleus. (T/F?)
  6. All output fibers from the cerebellum originate from the deep cerebellar nuclei. (T/F?)

  1. T
  2. F
  3. F
  4. T
  5. F
  6. F

  1. The cerebellum contains more neurons than the total from the rest of the brain, first of all because of the large number of the granule cells.
  2. There are three cerebellar peduncles that connect cerebellum with the rest of the brain, the superior cerebellar peduncle, the middle cerebellar peduncle and the inferior cerebellar peduncle.
  1. The globose and the emboliform nucleus form interposed nucleus.
  2. Most of the output fibers from the cerebellum originate from the deep cerebellar nuclei. The exception is the flocculonodular lobe, its output goes to the vestibular nuclei.

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13. Afferents to the cerebellum:

  1. The anterior spinocerebellar tract  carries proprioceptive information from muscle spindles and Golgi tendon organs of ipsilateral part of trunk and lower limb and enters the cerebellum through the inferior cerebellar peduncle. (T/F?)
  2. The anterior spinocerebellar tract crosses to the opposite side of the body first in the spinal cord as part of the anterior white commissure and then crosses again and enters the cerebellum via the inferior cerebellar peduncle. (T/F?)
  3. The cuneocerebellar tract enters the cerebellum via the inferior cerebellar peduncle on the opposite side. (T/F?)
  4. Tectocerebellar fibers enter the cerebellum via the middle peduncle from the ipsilateral midbrain colliculi. (T/F?)
  5. The pontocerebellar tract from the  ipsilateral  brainstem enters through the middle peduncle. (T/F?)
  6. Trigeminocerebellar fibers enter through the middle peduncle. (T/F?)

  1. F
  2. F
  3. F
  4. F
  5. F
  6. F

  1. The anterior or ventral spinocerebellar tract enters the cerebellum through the superior cerebellar peduncle. It crosses side first in the spinal cord as part of the anterior white commissure and then it crosses it again in the cerebellum, so it does carry proprioceptive information from the ipsilateral side of the body.
  2. Yes, it double-crosses side like it is explained but does not enter cerebellum through the inferior cerebellar peduncle
  3. The cuneocerebellar tract enters the cerebellum via the inferior cerebellar peduncle on the same side.
  4. Tectocerebellar fibers enter the cerebellum via the superior peduncle and they origin from the superior and inferior colliculi on both sides.
  5. The pontocerebellar tract from the contralateral  brainstem enters through the middle peduncle.
  6. Trigeminocerebellar fibers enter through the inferior cerebellar peduncle.

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5. Trigeminal nerve

  1. Is the largest cranial nerve. (T/F?)
  2. Is both motor and sensory nerve. (T/F?)
  3. Has three major branches:  the ophthalmic nerve, the maxillary nerve, and the mandibular nerve. (T/F?)
  4. One of its branches, mandibular nerve  comes close to the internal carotid artery in the cavernous sinus. (T/F?)
  5. Its motor nucleus supplies the muscles of mastication. (T/F)
  6. Maxillary and mandibular nerve have sensory and motor functions. (T/F?)

  1. T
  2. T
  3. T
  4. F
  5. T
  6. F

  1. First two branches of the trigeminal nerve, ophthalmic nerve (V1) and maxillary nerve (V2) pass through the cavernous sinus, while mandibular nerve (V3) does not.
  1. The ophthalmic and maxillary nerves are purely sensory, while the mandibular nerve has sensory and motor functions.


By Grant, John Charles Boileu (An atlas of anatomy, / by regions 1962) [Public domain], via Wikimedia Commons


By Grant, John Charles Boileu (An atlas of anatomy, / by regions 1962) [Public domain], via Wikimedia Commons


By Grant, John Charles Boileu (An atlas of anatomy, / by regions 1962) [Public domain], via Wikimedia Commons

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4. Oculomotor nerve

  1. Is the third cranial nerve. (T/F?)
  2. Has two nuclei: oculomotor nucleus and the Edinger-Westphal nucleus. (T/F)
  3. Runs in the lateral wall of the cavernous sinus. (T/F?)
  4. Enters orbit through the inferior orbital fissure. (T/F?)
  5. Its upper division supplies the superior rectus and the superior oblique muscles. (T/F?)
  6. Its inferior branch innervates medial rectus, inferior rectus and inferior oblique muscles. (T/F?)

  1. T
  2. T
  3. T
  4. F
  5. F
  6. T

  1. The Edinger–Westphal nucleus or accessory oculomotor nucleus is the parasympathetic pre-ganglionic nucleus that innervates the iris sphincter muscle and the ciliary muscle.
  2. Picture:

    Henry Vandyke Carter [Public domain], via Wikimedia Commons
  3. It enters the orbit via the superior orbital fissure.
    Henry Vandyke Carter [Public domain], via Wikimedia Commons
  4. The upper division supplies the superior rectus muscle and levator palpebrae superioris (elevating muscle of upper eyelid). The superior oblique muscle is innervated by the trochlear nerve (the fourth cranial nerve).

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3. Optic nerve

  1. Is also known as the second cranial nerve. (T/F?)
  2. Is wrapped around with Schwann cells. (T/F?)
  3. Is covered with all three meningeal layers. (T/F?)
  4. Leaves the orbit through superior orbital fissure. (T/F?)
  5. Is not affected with Guillain–Barré syndrome. (T/F?)
  6. Some of its axons terminate in the pretectal nuclei. (T/F?)

  1. T
  2. F
  3. T
  4. F
  5. T
  6. T

  1. The first is the olfactory nerve.
  2. The optic nerve is, actually, a part of the central nervous system because it is developed from the outgrowth of the diencephalon (optic vesicle, optic stalk). It is composed of retinal ganglion cells and glial cells and is covered by myelin produced by oligodendrocytes.
  3. They follow the nerve as it grows from the diencephalon.

    Henry Vandyke Carter [Public domain], via Wikimedia Commons
  4. It goes through the optic foramen and continues through the optic canal.
    Henry Vandyke Carter [Public domain], via Wikimedia Commons
  5. Hmm… GBS is primarily a peripheral demyelinating disease and it should not affect the optic nerve or any other part of CNS, but…
  6. Pretectal nuclei mediate functions like pupillary light reflex, optokinetic reflex and some others.

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2. Olfactory nerve

  1. Is the first cranial nerve (CN I). (T/F?)
  2. Is the second shortest of the cranial nerves. (T/F?)
  3. Emanates from the brainstem like all of the cranial nerves. (T/F?)
  4. Travels through cribriform plate of the ethmoid bone. (T/F?)
  5. Tumors of the frontal lobe of the brain can cause damage to the olfactory nerve. (T/F?)
  6. Lesions of the olfactory nerve  lead to a reduced ability to sense pain from the nasal epithelium. (T/F?)

  1. T
  2. F
  3. F
  4. T
  5. T
  6. F

    1. Olfactory nerve is the shortest of the cranial nerves.
    2. Olfactory nerve fibers arise from olfactory receptor cells located in the olfactory epithelium in the upper parts of the nasal cavity. They pass through the cribiform plate of the ethmoid bone to synapse in the olfactory bulb which lays in the anterior cranial fossa. The only other cranial nerve that does not join the brainstem is optic nerve.

By Patrick J. Lynch, medical illustrator (Patrick J. Lynch, medical illustrator) [CC BY 2.5], via Wikimedia Commons

  1. Pain from the nasal epithelium is carried to the central nervous system by the maxillary nerve.

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1. Trochlear nerve

  1. Is the smallest cranial nerve in terms of the number of axons it contains. (T/F?)
  2. Has the shortest  intracranial length. (T/F?)
  3. Is the one of two cranial nerves that exit from the dorsal (rear) aspect of the brainstem. (T/F?)
  4. Innervates superior oblique muscle, on the opposite side (contralateral) from its origin. (T/F?)
  5. Emerges from the dorsal aspect of the brainstem at the level of the caudal mesencephalon, just below the inferior colliculus, (T/F?)
  6. Enters the orbit through the superior orbital fissure. (T/F?)

  1. T
  2. F
  3. F
  4. T
  5. T
  6. T

  1. It is the smallest  in terms of the number of axons it contains.  The shortest is the olfactory nerve.
  2. Trochlear nerve has the longest intracranial length.
  3. Trochlear nerve is the only cranial nerve that exits from the dorsal aspect of the brainstem.

    Henry Vandyke Carter [Public domain], via Wikimedia Commons
  4. It is the only cranial nerve with contralateral innervation. It decussates within the mesencephalon before emerging on the opposite side of the brainstem. An injury to the trochlear nucleus in the brainstem will result in an contralateral superior oblique muscle palsy, whereas an injury to the trochlear nerve (after it has emerged from the brainstem) results in an ipsilateral superior oblique muscle palsy.