6/17: Nervous System and Nervous Tissue Homework
Some axons within the peripheral nervous system are unmyelinated. What relationship do these neurons have with Schwann cells? A. Schwann cells have multiple superficial grooves, each of which accommodates a single unmyelinated axon. B. Schwann cells have no relationship with these unmyelinated axons. C. Each Schwann cell wraps itself around a single unmyelinated axon, forming a sheath composed of many layers of cell membrane. D. Schwann cells enclose several neuronal cell bodies within a single deep groove.
A
The anatomical subdivisions of the nervous system are (the) ________. A. central and peripheral nervous systems B. autonomic and somatic nervous systems C. appendicular and axial nervous systems D. dorsal and ventral nervous systems E. None of the answers are correct.
A
After a head injury, which glial cells would try to repair the damaged area? A. oligodendrocytes and Schwann cells B. astrocytes and microglia C. satellite cells and microglia D. ependymal cells only
B
If the CNS were susceptible to a drug that should not affect it, this might indicate damage to which of the following cells? A. satellite cells B. astrocytes C. microglia D. Schwann cells E. ependymal cells
B
Microglia are (the) _______ A. most numerous neuroglial cell B. smallest neuroglial cell C. neuroglial cells that wrap the axons with a myelin sheath D. not a neuroglial cell E. None of the answers are correct.
B
The myelin sheath is functionally important because it __________. A. allows the conduction of different types of nerve impulses B. increases the conduction speed of nerve impulses C. reverses the direction of nerve impulse conduction D. decreases the conduction speed of nerve impulses
B
Which of the following is NOT a neuroglial function? A. engulfing pathogens that might infect the brain B. transmitting the image of a face from the eye to the visual cortex of the brain C. providing physical and metabolic support for neurons D. lining the central canal of the spinal cord
B
A biopsy of infected or injured tissue from the CNS will most likely show an elevated number of ________. A. satellite cells B. interneurons C. microglia D. ependymal cells E. oligodendrocytes
C
Collections of neuron cell bodies in the interior of the CNS form larger groups called ________. A. cranial nerves B. columns C. nuclei D. spinal nerves E. reverberating neurons
C
To contact a Schwann cell, where would a microprobe have to be inserted in the nervous system? A. anywhere in the CNS B. alongside an unmyelinated axon in the CNS C. along any axon in the PNS, myelinated or not D. near or at a neuron cell body E. None of the answers are correct.
C
Which of the following is FALSE regarding the myelin sheaths of neurons? A. Axons covered in myelin have faster action potential speeds than those without myelin. B. Schwann cells can myelinate only one segment of one axon, whereas oligodendrocytes can contribute myelin to many axons. C. Only large-diameter axons in the PNS are covered in myelin. Small-diameter axons are short and require no myelin. D. The gaps between areas of myelin are called nodes.
C
Which of the following statements is FALSE regarding the myelin sheath and myelination? A. Multiple Schwann cells are used to cover a myelinated axon in the PNS. B. A single oligodendrocyte may provide myelin for multiple CNS axons, linking them together. C. Myelinated axons are covered by Schwann cells in the CNS, whereas unmyelinated axons have no Schwann cells associated with them. D. The presence of a myelin sheath increases the speed of impulse transmission along the length of an axon.
C
Neuroglia in the nervous system function to ________. A. process information in the nervous system B. transfer nerve impulses from the brain to the spinal cord C. carry nerve impulses D. act as phagocytes E. All of the answers are correct.
D
Oligodendrocytes ________. A. maintain the blood-brain barrier and provide structural support B. remove cell debris, wastes, and pathogens by phagocytosis C. line the ventricles of the brain and the central canal of the spinal cord D. provide structural framework and myelinate the central nervous system (CNS) axons E. regulate oxygen, carbon dioxide, nutrient and neurotransmitter levels around neurons in ganglia
D
Functions of the nervous system include which of the following? A. receives sensory input; coordinates sensory input and motor output B. seat of higher functions, such as intelligence, memory, learning, and emotions C. regulates smooth muscle, cardiac muscle, and glandular activities D. integrating and processing data E. All of the answers are correct.
E
In the PNS, the neuron cell bodies are found in clusters called ________. A. tracts B. nuclei C. columns D. white matter E. ganglia
E
The portion of a neuron that carries information in the form of a nerve impulse (action potential) is called the
axon
The central nervous system (CNS) includes the
brain and spinal cord
Which cell monitors the composition of the CSF in the CNS?
ependymal cell
Which of the following neuroglia produce cerebrospinal fluid? A. microglia B. oligodendrocytes C. astrocytes D. satellite cells E. ependymal cells
ependymal cells
