Nervous System Review

These flashcards cover key vocabulary and concepts related to the nervous system.

Interneurons

Perform the integrative functions of the nervous system.

Voltage-gated ion channels

Highest density found in the myelin sheath gaps of a neuron.

Cell body of a mature neuron

Lacks centrioles.

Microglia

Glial cells that fight infections in the CNS.

Posttetanic potentiation

Increases the amount of calcium in the axon terminal.

IPSP

A hyperpolarization of the postsynaptic neuron.

Saltatory conduction

Occurs only in myelinated axons.

Neurotransmitter effects

Can be either excitatory or inhibitory depending on the receptor type.

Firing frequency

Differences in sound volume are likely encoded by differences in this in axons from the inner ear.

Reverberating circuits

Used for motor effects that depend on repetitive output from a neural pool.

Afferent neurons

Neurons that convey information to the CNS.

Properties of neurons

Excitability, secretion, and conductivity.

Absolute refractory period

Period during which a neuron cannot respond to another stimulus of any strength.

Dendrites

Specialized extensions of the cell that receive incoming signals.

Oligodendrocytes

Glial cells in the CNS that produce myelin.

Action potentials

Produced only in specialized regions called myelin sheath gaps.

Trigger zone

Consists of the axon hillock and initial segment of a neuron.

Norepinephrine

Neurotransmitter secreted at an adrenergic synapse.

Facilitated zone

Spaces where substances modify the neurotransmitter's effect.

Neurotransmitter

Biochemical substance that transmits signals across synapses.

Astrocytes

Most abundant glial cells in the CNS.

Extracellular concentration of Na+

Greater than its intracellular concentration.

EPSP

Brings the membrane potential closer to the threshold.

Myelin

Increases speed of signal transmission along axons.

Central nervous system (CNS)

Consists of the brain and spinal cord.

Peripheral nervous system (PNS)

Consists of nerves and ganglia outside the CNS.

Sensory division

Part of the PNS that transmits sensory information to the CNS

stimulus info for CNS

unipolar and bipolar

Motor division

Part of the PNS that sends signals to muscles and glands

effectors

Somatic nervous system

Controls voluntary movements.

Autonomic nervous system

Controls involuntary actions.

Sympathetic nervous system

Prepares the body for fight-or-flight responses.

Parasympathetic nervous system

Promotes rest-and-digest activities.

Enteric nervous system

Regulates functions of the gastrointestinal system.

Multipolar neurons

Most common type, having one axon and multiple dendrites

The most common type in the (body)

most neurons in CNS

Bipolar neurons

Have one axon and one dendrite, typically found in sensory organs.

Unipolar neurons

Have a single process leading away from the cell body

splits into peripheral process and central process

Neuroglia

Supporting cells in the nervous system.

Ependymal cells

Produce cerebrospinal fluid in the CNS.

multiple sclerosis is a disease where neurons have their myelination degraded. what effect would this have on the neuron?