nervous tissue: structure and function (mastering A&P)
What cells of the nervous system are responsible for anchoring neurons to their blood vessels and controlling the extracellular fluid concentrations of potassium and neurotransmitters?
astrocytes
What is the most abundant glial cell in the central nervous system (CNS)?
astrocytes
The Schwann cell forms a myelin sheath around the ________.
axon
The part of the neuron that typically conducts nerve impulses away from the cell body is the ________.
axon
What part of a neuron receives signals and sends a message to the cell body?
dendrite
The neuron processes that normally receive incoming stimuli are called ________.
dendrites
The cell bodies of the ________ neurons are always located within the CNS.
motor
Support cells in the central nervous system are collectively called ________.
neuroglia
The gaps between Schwann cells found at regular intervals in peripheral system neurons are called ________.
nodes of Ranvier
Which of these neuroglial cells forms the myelin sheath in the central nervous system?
oligodendrocytes
Bundles of nerve fibers (neuron processes) running through the CNS are called ________, whereas in the PNS they are called ________.
tracts; nerves
Myelinated fibers (tracts) form ________ matter while unmyelinated fibers form ________ matter.
white; gray
________ connect sensory and motor neurons in neural pathways and their cell bodies are typically located in the central nervous system.
Interneurons (association neurons)
Why is white matter "white"?
It contains a high concentration of myelin.
________ cells form the myelin sheaths around nerve fibers in the PNS.
Schwann
Ganglia are collections of ________.
cell bodies
Unmyelinated nerve fibers are known as ________.
gray matter
The two major functional properties of neurons are ________.
irritability and conductivity
Which of these is a deep pressure receptor?
lamellar corpuscle
Sensory receptors located in muscles and tendons are termed ________.
proprioceptors
