Ch. 3 - Biology and Behavior Flashcards
Neurons are:
individual cells in the nervous system that receive, integrate and transmit information
Soma is the:
the body of the cell— containing cell’s nucleus and organelles
Dendrites are… that specialize to…
parts of the neuron that are specialized to receive information— information moves from here through cell body
Axon is a… that…
long, thin fiber that transmits signals away from the soma to other neurons or to muscles or glands
Myelin sheath is an… that…
insulating material that encases some axons, that speeds up the transmission of signals that move along axons— also stabilizes axon structure and pattern of connectivity in neural networks
Terminal buttons are… that…
small knobs that secrete neurotransmitters (chemicals)
Synapses are the… where…
junction where information is transmitted from one neuron to another
“All-or-none” law for neurons is the need to… and is determined by…
need to reach a certain threshold to fire—strength is determined by how often the neuron fires
Glia are… found… that…
cells found throughout the nervous system that provide various types of support for neurons— supply nourishment to neurons, help remove waste products, provide insulation
Resting potential is ___, ___ charge when the cell is inactive
is stable, negative charge when the cell is inactive
Action potential is ___, and reflected by a…
very brief shift in a neuron’s electrical charge that travels along an axon— reflected by a voltage spike
Absolute refractory period is the…
Aka:
minimum length of time after an action potential during which another action potential cannot begin
Aka: ‘down time’
Synaptic cleft is a…
a microscopic gap between the terminal button of one neuron and the cell membrane of the next neuron
Presynaptic neuron ___ the signal while postsynaptic neuron ___ the signal
Presynaptic neuron that sends the signal
Postsynaptic neuron receives the signal
Synaptic vesicles are… that store ___ within…
small sacs that store chemicals (neurotransmitters) within the terminal buttons
Postsynaptic potential (PSP) is a… on a…
voltage change at a receptor site on a postsynaptic cell membrane— do not follow the all or none law
- instead they are graded or they vary in size which can increase/decrease the probability of a neural impulse in the receiving cell in proportion to the amount of voltage change
Excitatory PSP is a (positive/negative) voltage shift that increases/decreases…
positive voltage shift that increases the likelihood that the postsynaptic neuron will fire action potentials
Inhibitory PSP is a (positive/negative) voltage shift that increases/decreases…
negative voltage shift that decreases the likelihood that the postsynaptic neuron will fire action potentials
Reuptake is the process by which… by… — allows…
neurotransmitters are sponged up from the synaptic cleft by the presynaptic membrane— allows synapses to recycle their materials
Integrating signals is when a neuron must…before…
integrate the excitatory and inhibitory signals before it decides to fire an impulse
Synaptic pruning is synapses…
synapses elimination of old or less active
Peripheral nervous system os made up of…
all the nerves that lie outside the brain and spinal cord
Nerves are… that are…
bundles of neuron fibers (axons) that are routed together in the peripheral nervous system
Somatic nervous system os made up of… that…
made up of nerves that connect to voluntary skeletal muscles and sensory receptors
Afferent nerve fibers (axons) carry information inward to … from …
carry information inward to the central nervous system from the periphery of the body
Efferent nerve fibers (axons) that carry information from … to …
carry information outward from the central nervous system to the periphery of the body