Ch. 1 Flashcards
Chapter 1 of The Mind's Machine (158 cards)
Neurons
(Nerve cell)- the basic unit of the nervous system, each composed of receptive extensions called dendrites, an integrating cell body, a conducting axon, and a transmitting axon terminal
Glial Cells
Nonneuronal brain cells that provide structural, nutritional, and other types of support to the brain
Synapses
The cellular location (tiny gap) at which information is transmitted from a neuron to another cell
What are the four principal divisions of the neuron?
input zone=dendrites
integration zone=cell body
conduction zone=axon
output zone=axon terminals
Dendrites
An extension of the cell body that receives information from other neurons
Cell Body
The region of a neuron that is defined by the presence of the cell nucleus
Axon
Also called nerve fiber. A single extension from the cell body that carries action potentials from the cell body toward the axon terminals.
Axon Collaterals
A branch of an axon
Axon Terminals
The end of an axon or axon collateral, which forms a synapse onto a neuron or other target cell and thus serves as the output zone (transmits the neuron’s signal across synapses to other cells)
Motor Neurons
A neuron that transmits neural messages to muscles- shape is large with long axons
Sensory Neurons
A neuron that is directly affected by changes in the environment, such as light, odor, or touch. Conveys information from sense organs to the brain.
Interneurons
A nerve cell that receives input from and send output to other neurons
What are the three classifications of neuron shapes?
multipolar, bipolar, and unipolar neurons
Multipolar Neurons
has many dendrites and a single axon (most common type of neuron)
Bipolar Neurons
have a single dendrite at one end of the cell and a single axon at the other end (common in sensory systems)
Unipolar Neurons
(Also called monopolar neurons) has a single projection, serving as an axon that extends from the input zone to the axon terminals, with the cell body branching off part way along its length
Presynaptic
transmitting side of a synapse
Postsynaptic
region of a synapse that receives and responds to neurotransmitter
What 3 principal components can a synapse be divided into?
presynaptic membrane, synaptic cleft, and postsynaptic membrane
Presynaptic Membrane
The specialized membrane on the axon terminal of a nerve cell that transmits information by releasing neurotransmitter
Synaptic Cleft
The space between the presynaptic and postsynaptic cells at a synapse
Postsynaptic Membrane
The specialized membrane on the dendrite or cell body that receives information by responding to neurotransmitter from a presynaptic neuron
Synaptic Vesicles
A small, spherical structure that contains molecules of neurotransmitter. Contained within the presynaptic axon terminals.
Neurotransmitter
The signaling chemical released from the presynaptic axon terminal that diffuses across the synaptic cleft to alter the functioning of the postsynaptic neuron, which serves as the basis of communication between neurons