Chapter 2 Flashcards
Neuron or Nerve Cells
Basic Unit of the nervous system, which is composed of dendrites, an integrating cell body, an axon, and an axon terminal.
Glial Cells or Glia Cells
Nonneuronal brain cells that provide structural, nutritional, and other types of support to the brain.
Synapse
The cellular location where information is transmitted from a neuron to another cell.
Input Zone
Where the neuron collects and processes information from the environment or other cells.
Integration Zone
Where the neuron decides if necessary to produce a neural signal.
Conduction Zone
The area of the neuron where information can be electrically transmitted over great distances.
Output Zone
Where the neuron transfers information to other cells.
Dendrites
Extensions coming off the cell body of a neuron, where information is received. This is the main area that the input zone takes place.
Cell Body or Soma
The region of a neuron where the cell nucleus is. This is where the integration zone takes place.
Axon or Nerve Fiber
A single extension from nerve cells that carries action potentials (the information) from the cell body to the axon terminals. This is where the conduction zone takes place.
Axon Collateral
A branch of an axon.
Axon Terminal or Synaptic Bouton
The end of an axon or axon collateral which forms a synapse onto either another neuron or other cell to transfer the information to. This is where the output zone occurs.
Motor Neurons or Motoneuron
A neuron that transmits neural messages to muscles or glands. Motor Neurons are often very long.
Sensory Neurons
These nerve cells gather sensory information, like light, touch, smell, etc.
Interneurons
A nerve cell that receives inputs from nerve cells and then outputs to other nerve cells. An interneuron allows the sensory neurons to send information to motor neurons. Also interneurons can communicate between each other.
Multipolar Neurons
A nerve cell that has many dendrites extending from the soma. It also has just a single axon, so no axon collateral.
Bipolar Neurons
A nerve cell that has a single dendrite extending from the soma. It has just a single axon, so no axon collateral.
Unipolar Neurons
A nerve cell that has a single branch that extends in two directions. This branch serves as the dendrite and the axon.
Presynaptic Neuron
The neuron that will be transferring information. Presynaptic means located on the transmitting side of a synapse.
Postsynaptic Neuron
The neuron that will be receiving information.
Presynaptic Membrane
The membrane on the axon terminal of a nerve cell that transmits information by releasing a neurotransmitter.
Postsynaptic Membrane
The membrane on the surface of a neuron that receives information by responding to the neurotransmitter from a presynaptic neuron.
Synaptic cleft
The space between the presynaptic and postsynaptic neurons at a synapse.
Synaptic vesicle
A small, spherical structure that contains molecules of the neurotransmitter.
Neurotransmitter or Synaptic transmitter
The chemical released from the presynaptic axon terminal that serves a the basis of communication between neurons.
Neurotransmitter Receptor
A protein that selectively senses and reacts to molecules of a corresponding neurotransmitter or hormone.
Neuroplasticity
The ability of the nervous system to change in response to an experience or the environment.
Axon hillock
The cone shaped are on the cell body from which the axon originates.
Innervate
To provide neural input. (supply with nerves)
axonal transport
The transportation of materials from the neuronal cell body toward the axon terminals back toward the cell body.
Oligodendrocyte
Type of glial cell that forms myelin in the central nervous system. The myelin sheaths cover the axons on neurons.
Schwann Cell
A type of glial cells that form myelin in the peripheral nervous system.
Myelin
A fatty insulation around an axon, formed by glial cells. This sheath boosts speed at which nerve impulses are conducted.
Node of Ranvier
A gap between the successive segments of myelin sheaths where the axon terminal is exposed.
Astrocyte
Star shaped glial cell that is responsible for helping define the structure of the brain and help control blood flow depending on where the brain is active the most.
Microglial cells
Small motile cells that remove cellular debris from injured or dead cells. Also they have recently been found to also be involved in pain perception.
Edema
General term referring to swelling of any body tissue, including the brain.
Gross anatomy
Anatomical features of the nervous system that are apparent to the naked eye.
Central Nervous System (CNS)
The portion of the nervous system that includes the brain and spinal cord.
Peripheral Nervous System (PNS)
The portion of the nervous system that includes all the nerves and neurons outside the brain and spinal cord.
Nerve
A collection of axons bundled together outside the central nervous system.
Motor Nerve
A nerve that transmits information from the central nervous system to the muscles and glands.
Sensory Nerve
A nerve that conveys information from the body to the central nervous system.
Somatic Nervous System
A part of the peripheral nervous system that supplies neural connections mostly to the skeletal muscles and sensory systems of the body. It consists of cranial nerves and spinal nerves.
Autonomic Nervous System
A part of the peripheral nervous system that provides the main neural connections to the internal organs.
Cranial Nerve
A nerve that is connected directly to the brain.
Spinal Nerve
A nerve that emerges from the spinal cord.
Cervical
Refers to the topmost eight segments of the spinal cord, it is in the neck region.
Thoracic
Referring to the 12 spinal segments below the cervical portion of the spinal cord, this is in the torso region.