WS: histology of nerve tissue and nervous system

Question 12 1 / 1 pts Which term applies to collections or groups of neuronal cell bodies (somata) in the central nervous system? Nuclei Neuroglia Neuroglia White matter Ganglia

Nuclei

Question 10 1 / 1 pts Following an episode of severe head trauma in a motorcycle accident, an 18-year-old woman is noted to have decerebrate posturing. Funduscopic examination reveals marked bilateral papilledema. A CT scan of the head reveals marked diffuse cerebral edema from an increase in sodium and water content. There is effacement of lateral ventricles. Which of the following epithelial-like glial cells lines the lateral ventricles? Microglial Satellite Oligodendrocytes Ependymal

Ependymal

Question 3 1 / 1 pts Episodes of demyelination are associated with which of the following? meningitis multiple sclerosis spina bifida Huntington chorea Parkinson disease

Multiple sclerosis is the correct answer. It is an immune-mediated disease exhibiting chronic and progressive dysfunction of the nervous system due to demyelination of the CNS and optic nerves, striking the 20-to-40-year age group and affecting 1.5 times more women than men. There are random episodes of inflammation, edema, and demyelination of axons followed by periods of remission. Each episode may reduce the vitality of the patient and be sufficient to cause death within months.

Question 2 1 / 1 pts Myelination of peripheral nerves is accomplished by which of the following? basket cells. oligodendrocytes astrocytes Schwann cells neural crest cells

Schwann cells is the correct answer. They produce myelin in the PNS, whereas oligodendrocytes produce myelin in the CNS. Astrocytes, neural crest cells, and basket cells do not produce myelin.

Question 4 1 / 1 pts Which of the following statements characterizes the structure and function of neurons? Some of the cell bodies of neurons are located in the ganglia A neuron may have more than one axon Some of the dendrites are covered with myelin sheaths Nissl bodies are components of the axon Anterograde transport goes from the axonal terminal towards the soma

Some of the cell bodies of neurons are located in the ganglia is the correct answer. The ganglia in the PNS contain clusters of cell bodies of neurons. Axons, when thick enough, are myelinated, and myelinated axons (nerve fibers) are located in both the CNS and the PNS. Dendrites are not nerve fibers, and they don't have myelin sheaths. Nissl bodies are located in the soma and some of the large dendrites, but they cannot enter the axon hillock, therefore, they cannot be found in the axon. Anterograde transport goes from the soma towards the axonal terminal, and retrograde transport goes from the axonal terminal towards the soma. Neurons may have different numbers of dendrites, but each neuron can only have one axon.

Question 7 1 / 1 pts A 56-year-old man presents with neurological deficits and a CT scan suggests patches of nervous tissue degeneration and the formation of scar tissue in his brain. Which of the following cell types produces scar tissue in the central nervous system (CNS)? Ependymal cells Microglial cells Astrocytes Oligodendrocytes Schwann cells

The correct answer is astrocytes. One function of astrocytes is to form scar tissue in the CNS. Ependymal cells line the luminal surface of the ventricular system of the CNS. Microglial cells are the phagocytes in the CNS. The function of Schwann cells and oligodendrocytes is to produce myelin sheaths. Schwann cells are exclusively located in the PNS, and oligodendrocytes are exclusively located in the CNS.

Question 5 1 / 1 pts Which of the following type of glial cells is derived from the bone marrow? Schwann cells Oligodendrocyte Astrocyte Microglia Neurons

The correct answer is microglia. Oligodendrocytes and astrocytes are derived from the embryonic neural tube. For neurons, if the cell body of a neuron is located in the CNS (such as somatic motor neurons), this neuron is derived from the embryonic neural tube; if the cell body of a neuron is located in the PNS (such as neurons in sensory ganglia and autonomic ganglia), this neuron is derived from the neural crest cells. Schwann cells are derived from the neural crest cells. Microglia are derived from the bone marrow.

Question 8 1 / 1 pts What is the name for the network of cellular processes emerging from neurons and glial cells in the central nervous system (CNS)? Grey matter Ganglia Neuropil White matter Neurofilaments

The correct answer is neuropil. White matter refers to an area of nervous tissue with a lot of myelinated axons, grey matter lacks these. Ganglia are where neuronal cell bodies are located in the peripheral nervous system (PNS). Neurofilaments are the type of intermediate filaments found in neurons.

Nissl bodies are composed of which of the following? polyribosomes and rough endoplasmic reticulum. lipoprotein and melanin. SER and mitochondria synaptic vesicles and acetylcholine. neurofilaments and microtubules.

The correct answer is polyribosomes and rough endoplasmic reticulum. Nissl bodies are large, granular basophilic bodies composed of polysomes and RF.R. They are found only in neurons (in the soma cytoplasm).

Question 9 1 / 1 pts Where would a neuron with the regular well know structure most likely to be found? Spinal ganglia Spinal cord Cranial ganglia Retina

The correct answer is spinal cord. This is a drawing of a multipolar neuron, which contains a single axon and multiple dendrites. This is the most common type of neuron, including all motor neurons and CNS interneurons, and they are located in the grey matter of the spinal cord. Retina is a bipolar neuron. Spinal ganglia and Cranial ganglia are unipolar/pseudounipolar neurons (different sources use these terms interchangeably). Note that all spinal ganglia but only most cranial ganglia are unipolar/pseudounipolar.

Question 6 1 / 1 pts Which of the following statements characterizes the structure of the peripheral nerves? A peripheral nerve contains either sensory nerve fibers or motor nerve fibers, but not both The epineurium surrounds the individual bundles of nerve fibers There are no unmyelinated axons within the peripheral nerves The endoneurium wraps around the individual nerve fibers The entire peripheral nerve is covered by the perineurium

The endoneurium wraps around the individual nerve fibers is the correct answer. Depending on the location and function of a peripheral nerve, it may contain only sensory nerve fibers or motor nerve fibers, or in most cases, both sensory and motor nerve fibers. A peripheral nerve contains bundles of nerve fibers, and some nerve fibers are myelinated and some are unmyelinated. The individual nerve fibers are surrounded by the endoneurium; bundles of those nerve fibers together are wrapped around by the perineurium. Then several bundles will be surrounded together by the epinuerium, which is the outermost connective tissue covering a peripheral nerve.