08 Nervous System

The arachnoid has two parts: A layer of connective tissue adjacent to the pia mater, and a network of collagen and fibroblasts, connected to the dura mater. An outer layer of white matter, and an inner layer of gray matter. A layer of connective tissue adjacent to the dura mater, and a network of collagen and fibroblasts, connected to the pia mater. A layer of ependymal tissue, and a layer of pia mater.

A layer of connective tissue adjacent to the dura mater, and a network of collagen and fibroblasts, connected to the pia mater.

The blood-brain barrier is made up of three parts: a capillary endothelium in which the cells are tightly connected and allow almost no passage of substances, a basement membrane that envelopes the capillaries, and A network of neuropil A layer of perivascular astrocytic "feet" Pia mater Myelin sheath

A layer of perivascular astrocytic "feet"

Sensory nerve fibers are: Both afferent and efferent Afferent Neither afferent nor efferent Efferent

Afferent (afferent connection arrives and an efferent connection exits)

Which of these substances can pass through the blood-brain barrier? Caffeine All of these. Alcohol Nicotine

All

Which of these is true? All are true. The subdural space is not "real" in that it is created by an artifact of tissue preparation. The arachnoid has blood vessels that enter the brain, carrying oxygen. Arachnoid villi release excess CSF into the blood

All are true.

Which of these is true of the Node of Ranvier? It aids in conduction of the action potential along axons. It forms the gap between Schwann cells. All of these are true It forms a gap in the myelin sheath

All of these are true

Which of these is true? Ganglia are made of clusters of nerve cell bodies in the PNS Tracts are part of the CNS only, not the PNS All of these are true. Nerves are part of the PNS only, not the CNS.

All of these are true.

The choroid plexus consists of ependyma and vascularized pia mater. It functions as a type of barrier between: CSF and the brain Blood and the CSF None of these Blood and the brain

Blood and the CSF

What protects neurons and glia from bacterial toxins, infectious agents, etc., and maintains the composition and balance of ions in the interstitial fluid? Arachnoid None of these. Blood-Brain barrier Dura mater

Blood-Brain barrier

Typically, a spinal nerve has: Only sensory fibers Tracts Both sensory and motor fibers Only motor fibers

Both sensory and motor fibers

Ganglia are clusters of neuron cell bodies in the PNS. In the CNS, clusters of neuron cell bodies are called: Nerves Cerebral nuclei Schwann cells Tracts

Cerebral nuclei

One of the functions of the sub-arachnoid space is to: Prevent dehydration of interstitial matrix. Cushion the CNS from damage Maintain osmotic pressure with the blood Production of CSF

Cushion the CNS from damage

Which of these has only sensory fibers? Anterior Ramus of spinal nerve Posterior Ramus of spinal nerve Ventral root of spinal cord Gray matter Dorsal root of spinal cord

Dorsal root of spinal cord

What are the components of the choroid plexus? Ependyma and pia mater with blood vessels. Arachnoid and pia mater Ependyma only CSF and dura mater

Ependyma and pia mater with blood vessels.

Around the spinal cord, the dura mater is separated from the periosteum of the vertebrae by the: Subdural space Epidural space Arachnoid None of these.

Epidural space

In a ___________________, blood from the middle meningeal artery accumulates between the skull bones and the dura mater. Subdural hematoma Subarachnoid hemorrhage Extradural hemorrhage None of these.

Extradural hemorrhage

Where in the nervous system do most synapses occur? Gray matter Tracts None of these is correct. White matter

Gray matter

The autonomic nervous system regulates or manages: Neural plasticity Sensory input Skeletal muscle activity Homeostasis

Homeostasis

The Nodes of Ranvier contribute to saltatory conduction. Which is true? In saltatory conduction the action potential is faster than that in unmyelinated fibers. Saltatory conduction is only found in sensory fibers. Saltatory conduction occurs only in the CNS. In saltatory conduction the axons are unmyelinated.

In saltatory conduction the action potential is faster than that in unmyelinated fibers.

Where is the choroid plexus found? In the subarachnoid space Between the dura mater and the skull bones In the roofs of the 3rd and 4th brain ventricles In the cerebral ventricles

In the roofs of the 3rd and 4th brain ventricles

The pia mater is closely applied to the entire surface of the CNS tissue. What is its function? It forms a physical barrier separating CNS tissue from CSF in the subarachnoid space. It forms a vascular network separating CNS tissue from CSF in the subarachnoid space. It forms a vascular network separating the dura mater from the arachnoid. None of these.

It forms a physical barrier separating CNS tissue from CSF in the subarachnoid space.

What is the caudal equina? It is a collection of cranial nerves that supplies the muscles of the jaws. None of these. It is the collection of the spinal nerves searching the lumbar, coccygeal, and sacral regions. It is the site of epidural anesthesia.

It is the collection of the spinal nerves searching the lumbar, coccygeal, and sacral regions.

From where does the arachnoid layer get its name? None of these. It resembles a tissue found in spiders. It has eight regions, like the eight legs of a spider It resembles a spider web.

It resembles a spider web.

Myelin is composed of: Proteins only Lipids and proteins Lipids and proteoglycans Lipids and GAGs

Lipids and proteins

Which of the glial cells has a function in immune responses? Oligodendrocytes Microglia Ependymal cells Astrocytes

Microglia

In general, the descending pathways of the central nervous system are composed of what type of nerve fibers? Sensory Sensory and motor Motor Autonomic

Motor

The anterior horns of the spinal cord contain mainly cell bodies of ___________________. Sensory neurons Both sensory and motor neurons Motor neurons Interneurons

Motor neurons

In the PNS, bundles of myelinated axons are called: Sympathetic nerve fibers Tracts Purkinje fibers Nerves

Nerves

The central canal of the spinal cord and the ventricles of the brain are formed from the embryonic ____________. Neural tube Blood-brain barrier Choroid plexus Subarachnoid space

Neural tube

A bundle of myelinated axons is called a fascicle. It is covered by: Epineurium None of these Perimysium Endoneurium

None

The ventricles of the brain are filled with: Blood Water Lymph None of these

None

Which tract conveys information about pain and temperature? Corticospinal pathway None of these. Anterior spinothalamic tract Spinocerebellar tract

None of these.

How many pairs of thoracic nerves are there in humans? None of these. 11 5 8

None of these. (12)

Which cells form the myelin sheathes of cells in the CNS? Schwann cells Oligodendrocytes None of these. Satellite Cells

Oligodendrocytes

The dura mater is: The layer of tissue that produces cerebrospinal fluid The region of the brain where epinephrine is produced One of the meninges of the CNS A type of cell that forms myelin around the axon

One of the meninges of the CNS

Ganglia are clusters of nerve cell bodies that are found: Only associated with the brain Only associated with the spinal cord, and not with the brain. Only in the peripheral nervous system Only in the central nervous system

Only in the peripheral nervous system

Which meningeal layer lies between the CSF and the tissue of the CNS: Arachnoid Subarachnoid space Pia mater Dura mater

Pia

Where in the brain is the somatosensory cortex located? Temporal lobe Postcentral gyrus Frontal lobe Precentral gyrus

Postcentral gyrus

The blood-brain barrier protects the CNS from harmful agents. It also: Restores low blood pressure to a normal level. None of these. Prevents passage of some clinically important drugs. Produces CSF by filtering blood plasma.

Prevents passage of some clinically important drugs.

Which of these general effects is associated with the sympathetic division of the ANS? Rest-and-digest Dampening of responses Quick response Feed-and-breed

Quick response

A subarachnoid hemorrhage may result from a: Tearing of a cerebral vein. All of these. Saccular aneurysm Rupture of the middle meningeal artery

Saccular aneurysm

Which type of glial cells are associated with ganglia? Satellite cells None of these. Astrocytes Schwann cells

Satellite cells

Which cells form myelin sheathes of axons in the PNS? Microglia Schwann Cells Oligodendrocytes Ependymal cells

Schwann Cells

Which of these tracts carry "unconscious" information about body position? Spinothalamic tract None of these. Spinocerebellar tract Dorsal column-medial lemniscos pathway

Spinocerebellar tract

What is filled with CSF and cushions and protects the CNS? Arachnoid Subdural space Loose connective tissue Subarachnoid space

Subarachnoid space

The autonomic nervous system differs anatomically from somatic nerve pathways in that: The ANS is restricted to the central nervous system The ANS has both sensory and motor neurons The ANS has a two-neuron efferent pathway The ANS has a one-neuron efferent pathway

The ANS has a two-neuron efferent pathway (afferent connection arrives and an efferent connection exits)

Which one of these is true? The cell bodies of the postsynaptic neurons of the sympathetic system lie in the sympathetic chains (paravertebral) and in prevertebral ganglia. The cell bodies of the presynaptic neurons of the parasympathetic system lie in the thoracic and lumbar regions of the spinal cord. The cell bodies of the postsynaptic neurons of the parasympathetic system lie in the sympathetic ganglia of the head. The cell bodies of the presynaptic neurons of the sympathetic system lie in the white matter of the spinal cord,

The cell bodies of the postsynaptic neurons of the sympathetic system lie in the sympathetic chains (paravertebral) and in prevertebral ganglia.

White matter is white because of: The lack of vasculature The thickness of the cell membranes The abundance of glycoproteins in the ground substance The lipid content of the cell membrane sheaths

The lipid content of the cell membrane sheaths

What is the clinical advantage of knowing the location of the various dermatomes? Understanding dermatome distribution is important in treating autoimmune diseases. Knowing this informs the clinician which skin regions are affected by the cranial nerves. None of these. This knowledge can help diagnose which spinal nerves may be damaged.

This knowledge can help diagnose which spinal nerves may be damaged.

Which of these characteristics is associated with the sympathetic division? Norepinephrine as a neurotransmitter Thoracolumbar outflow. Presynaptic neurons found in brainstem and sacral spinal cord. Postsynaptic ganglia are associated directly with organs such as lungs and heart

Thoracolumbar outflow

In the CNS, bundles of myelinated axons are called: Gray matter Tracts Nerves Cerebral cortex

Tracts

Which of these does NOT describe a general function of the autonomic nervous system? Regulation of heart rate Response of pupils to light. Voluntary muscle control Stimulation of secretion of hormones

Voluntary muscle control

What happens at the tissue level in Multiple Sclerosis? White blood cells penetrate the blood-brain barrier and attach the myelin sheath. Acetylcholine neurotransmitters are not produced by the neuron. An acute hemorrhage of a cerebral artery has occurred. None of these.

White blood cells penetrate the blood-brain barrier and attach the myelin sheath.

The epineurium: None of these. Surrounds the fascicles of nerve fibers Surrounds the Schwann cells. Wraps the entire nerve in a layer of connective tissue

Wraps the entire nerve in a layer of connective tissue

Select ALL of these that are effects of the parasympathetic division. • Contracts internal sphincter of bladder • Constricts the bronchi • Contraction of ciliary muscle. • Constriction of pupil • Increase in rate and strength of heart contraction • Secretion by the lacrimal glands • Breakdown of glycogen to glucose

• Constricts the bronchi • Contraction of ciliary muscle. • Constriction of pupil • Secretion by the lacrimal glands