Central Nervous System MCQs - Section 1 & 2

<p>S1/2 (B)</p> Signup and view all the answers

<p>Ankle jerk reflex (D)</p> Signup and view all the answers

<p>In the arachnoid mater (C)</p> Signup and view all the answers

<p>Anterior communicating unites middle and anterior cerebral (C)</p> Signup and view all the answers

<p>Internal carotid artery (B)</p> Signup and view all the answers

<p>Both cortexes and other structures (B)</p> Signup and view all the answers

<p>It has significant connections to the anterior communicating artery (C)</p> Signup and view all the answers

<p>Anterior pituitary (D)</p> Signup and view all the answers

<p>Middle cerebral artery (D)</p> Signup and view all the answers

<p>Midbrain (B)</p> Signup and view all the answers

<p>Pons (C)</p> Signup and view all the answers

<p>Diencephalon (B)</p> Signup and view all the answers

<p>Facial nerve (VII) (B)</p> Signup and view all the answers

<p>The femoral nerve is formed from L2, 3, 4 (D)</p> Signup and view all the answers

<p>Trochlear nerve (IV) (A)</p> Signup and view all the answers

<p>Parasympathetic innervation comes from S2-S4 segments of the spinal cord (B)</p> Signup and view all the answers

<p>The anterior spinal artery arises from the vertebral artery (C)</p> Signup and view all the answers

<p>Superior colliculus (A)</p> Signup and view all the answers

<p>Foramen magnum (B)</p> Signup and view all the answers

<p>20-50 micrometre (A)</p> Signup and view all the answers

<p>Inferior oblique (C)</p> Signup and view all the answers

<p>C6 (C)</p> Signup and view all the answers

<p>Pons (B)</p> Signup and view all the answers

<p>It supplies the mucous membrane of the posterior third of the tongue. (C)</p> Signup and view all the answers

<p>Great auricular nerve (B)</p> Signup and view all the answers

<p>Trochlear nerve (B)</p> Signup and view all the answers

<p>It exits the skull entirely through the foramen ovale. (D)</p> Signup and view all the answers

<p>A continuous area of skin supplied by a single spinal nerve root. (D)</p> Signup and view all the answers

<p>C5, 6 (C)</p> Signup and view all the answers

<p>Infraorbital nerve (B)</p> Signup and view all the answers

<p>Tractus solitarius (B)</p> Signup and view all the answers

<p>Afferent tendon stretch impulses (A)</p> Signup and view all the answers

<p>Greater occipital (A)</p> Signup and view all the answers

<p>Geniculate (C)</p> Signup and view all the answers

<p>It results in motor aphasia. (B)</p> Signup and view all the answers

<p>Supplies blood to the contralateral leg (B)</p> Signup and view all the answers

<p>Infraorbital nerve (A)</p> Signup and view all the answers

<p>Involves auditory comprehension (A)</p> Signup and view all the answers

<p>Innervates the back of the head (B)</p> Signup and view all the answers

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The blood-brain barrier (BBB) is a highly selective semipermeable membrane that separates the circulating blood from the brain's extracellular fluid in the central nervous system (CNS).

The middle cerebral artery is the largest branch of the internal carotid artery. It supplies a large portion of the brain, including the lateral surface of the cerebral hemisphere.

The diencephalon is not part of the brain stem. It is situated above the brain stem and is responsible for regulating several crucial homeostatic functions.

The abducens nerve (VI) emerges from the junction between the pons and medulla. It is responsible for controlling the lateral rectus muscle of the eye, which helps with eye movement.

The trochlear nerve (IV) is the smallest cranial nerve, responsible for controlling the superior oblique muscle of the eye, which helps with downward and outward eye movement.

The superior colliculi are located in the midbrain and are specifically involved in general light reflexes. They receive input from the retina and help with visual processing and orienting the eyes towards stimuli.

The medulla oblongata is the lowermost part of the brainstem, connecting to the spinal cord. It passes through the foramen magnum, the opening at the base of the skull.

The lateral rectus muscle is the only eye muscle that is NOT controlled by the oculomotor nerve (III). It is controlled by the abducens nerve (VI) and helps with eye movements to the side.

The motor nuclei for the trigeminal nerve (CN V) are located in the pons, specifically posterior to the cerebral aqueduct.

The motor nuclei for the facial nerve (CN VII) are located in the pons.

The lumbar plexus is formed by the ventral rami of the L1-L4 spinal nerves. The femoral nerve, which controls hip flexion and knee extension, is formed by L2-L4.

The parasympathetic innervation of the bladder comes from the pelvic splanchnic nerves. Sympathetic innervation comes from the L1-L2 spinal segments. Sympathetic innervation is excitatory to the bladder, while parasympathetic innervation is inhibitory.

The anterior spinal artery is a single artery that supplies the anterior aspect of the spinal cord. It receives blood from vertebral arteries.

Motor nerve fibers are typically larger than sensory fibers. This is because they need to conduct signals more quickly over longer distances.

The dermatome for the index finger is C7. The nipple is supplied by T4-T6. The umbilicus is supplied by T10.

The opponens pollicis muscle is innervated by the median nerve (C8, T1). Shoulder abduction is mainly controlled by the axillary nerve (C5, C6). Elbow extension is primarily controlled by the radial nerve (C7, C8) and the triceps brachii muscle.

The superior cerebral vein travels within the arachnoid mater, lying close to the brain's surface.

The abducens nerve (VI) controls the lateral rectus muscle, responsible for moving the eye outward (abduction).

The circle of Willis is a network of arteries at the base of the brain. The ophthalmic artery, supplying the eye, branches off from the internal carotid artery.

The falx cerebri is a fold of dura mater that separates the two cerebral hemispheres. The superior sagittal sinus, which collects venous blood from the brain, lies in the margins of the falx.

The brain stem consists of the midbrain, pons, and medulla oblongata. Unlike the diencephalon (which controls vital functions), it is NOT part of the brain stem.

The sensory root of the facial nerve is responsible for taste sensation from the anterior two-thirds of the tongue. It is part of the facial nerve complex but has separate functions.

The trigeminal nerve is a mixed nerve with sensory and motor components, responsible for innervation to the face, teeth, and scalp. The mandibular division is the only one that contains motor fibers.

The cervical sympathetic trunk is responsible for sympathetic innervation to the head and neck, including vasoconstriction, sweating, and pupil dilation.

A dermatome is a specific area of skin innervated by a single spinal nerve root. Each dermatome is associated with a single spinal nerve.

Myotomes are groups of muscles that are innervated by a single spinal nerve root. They help control specific movements.

The midbrain, located between the pons and the upper spinal cord, contains crucial nuclei for eye movement and other important functions.

The cerebrospinal fluid, a clear fluid that protects and nourishes the brain and spinal cord, circulates through the ventricles and the subarachnoid space. It communicates with the subarachnoid space through the 4th ventricle and subarachnoid granulations.

The spinocerebellar pathway is responsible for conveying sensory information from the spinal cord to the cerebellum, playing a crucial role in posture and coordination, while the vestibulospinal pathway is involved in regulating balance and movements.

The posterior column carries information about proprioception, touch, and vibration sensations.

The infratrochlear nerve supplies sensation to the medial part of the lower eyelid, the bridge of the nose, and the conjunctiva.

The greater occipital nerve supplies the vertex of the scalp, which is the highest point of the head.

Corneal sensation synapses in the ciliary ganglion, which is a collection of nerve cells that relay sensory signals.

Damage to Broca's area results in motor aphasia, making it difficult to produce speech.

The trochlear nerve (IV) controls the superior oblique muscle, which allows the eye to look downwards and outwards.

The middle cerebral artery supplies the contralateral arm, leg, and speech areas.

The septum of the nasal cavity is innervated by the nasopalatine nerve, which is a branch of the maxillary nerve (V2).

Anterior nerve roots carry signals AWAY from the spinal cord, responsible for movement and other motor functions. They are part of the peripheral nervous system.

The posterior rami of spinal nerves supply muscles in the back, like those involved in posture and movement of the spine.

The dermatome for the lateral half of the ankle is S1. This means that the skin in this area is supplied by the S1 spinal nerve.

The myotome for shoulder abduction is C5. This means that the muscle responsible for raising your arm away from your body is supplied by the C5 spinal nerve.

The myotome for hip extension is L4/L5, which means the muscles responsible for extending your leg backward are supplied by these spinal nerves.