Nerve Tissue & The Nervous system

Which of the following is characteristic of the chromatophilic material called Nissl substance in neural tissue?

• Found throughout neurons

• Site of mRNA translation for proteins of the axolemma

• Most abundant in unipolar neurons

• Becomes more abundant as an individual gets older

• An example of intermediate filament proteins

Which of the following events occurs immediately after an action potential reaches a synapse at an axon terminal?

• Vesicle fusion with the presynaptic terminal membrane

• Calcium ion influx at the presynaptic terminal

• Neurotransmitter binding to receptors on the postsynaptic membrane

• Neurotransmitter release into the synaptic cleft

• Binding of the neurotransmitter at the presynaptic terminal

A report from a hospital pathology laboratory indicates that a microscope slide with a small specimen of neural tissue contains “numerous GFAP-positive” cells. What is the most likely source of this specimen?

• A region of white matter

• A sensory ganglion

• An autonomic ganglion

• A region of gray matter

• Pia mater

In the choroid plexus water from capillaries is transported directly into the cerebrospinal fluid by what structure(s)?

• Ependyma

• Astrocytes

• Cells of the arachnoid mater

• Lining of the central canal

• Microglial cells

What term applies to collections of neuronal cell bodies (somata) in the central nervous system?

• Ganglia

• Neuroglia

• Nodes

• White matter

• Nuclei

Which structure contains trabeculae around which cerebrospinal fluid (CSF) flows?

• Arachnoid mater

• Ependyma

• Dura mater

• Pia mater

• Gray matter

Which of the following is a characteristic of the connective tissue layer that surrounds individual fascicles in large peripheral nerves?

• A delicate region of connective tissue in contact with Schwann cells

• Called the dura mater

• Rich in myelin

• The thickest sheath of connective tissue in the nerve

• Important as part of the blood-nerve barrier in the nerve

A 35-year-old woman presents with weakness and spasticity in the lower left extremity, visual impairment and throbbing in the left eye, and difficulties with balance, fatigue, and malaise. There is an increase in CSF protein, elevated gamma globulin, and moderate pleocytosis. MRI confirms areas of demyelination in the anterior corpus callosum. Imaging identifies plaques that are hyperintense on T2-weighted and fluid attenuated inversion recovery (FLAIR) images, and hypointense on T1-weighted scans. Which of the following cells are specifically targeted in her condition?

• Microglia

• Oligodendrocytes

• Astrocytes

• Schwann cells

• Multipolar neurons

A 22-year-old man receives a severe, traumatic compression injury to his radial nerve during a motorcycle crash. He shows an advancing Tinel sign. Which one of the following characterizes regeneration of axons after this nerve injury?

• It occurs in the absence of motor nerve action potentials.

• It occurs at a rate of about 100 mm/d.

• It occurs in the segment distal to the site of axon damage.

• It occurs by a process that involves Schwann cell proliferation.

• t occurs in conjunction with degeneration and phagocytosis of the endoneurium.

A 2-year-old boy presents with hearing impairment, poliosis (a white shock of hair), complete heterochromia and sectoral heterochromia, hypertelorism, a low hairline with eyebrows that touch in the middle, white pigmentation of the skin, and suspected neurologic deficits. He is diagnosed with Waardenburg syndrome with a mutation in the PAX-3 gene that affects neural crest differentiation. Which of the following structures would most likely also be affected in this patient

• Purkinje cells

• Pyramidal neurons

• Ventral horns of the spinal cord

• Astrocytes

• Neurons and satellite cells of the spinal ganglion