Nervous System Overview

These flashcards cover key concepts and terminology related to the nervous system as outlined in the lecture notes.

Integrative functions of the nervous system

Performed mainly by afferent neurons, efferent neurons, neuroglia, sensory neurons, and interneurons.

Highest density of voltage-gated ion channels

Found in the axon terminals of a neuron.

Cell body of a mature neuron

Lacks centrioles and has a nucleus, endoplasmic reticulum, and ribosomes.

Glial cells that fight infections in the CNS

Microglia.

Posttetanic potentiation of a synapse

Increases neurotransmitter amount in the axon terminal.

An IPSP is

Hyperpolarization of the postsynaptic neuron.

Saltatory conduction occurs

Only at myelinated axons.

Some neurotransmitters can have either excitatory or inhibitory effects depending on

The type of receptors on the postsynaptic cell.

Differences in the volume of sound are likely to be encoded by differences in

Firing frequency in axons from the inner ear.

Motor effects that depend on repetitive output from a neural pool

Are most likely to use reverberating circuits.

Neurons that convey information to the CNS are called

Sensory or afferent neurons.

Properties neurons must have to perform their role

Excitability, secretion, and conductivity.

Absolute refractory period

A period of time in which a neuron is producing an action potential and cannot respond to another stimulus.

Myelin in the CNS is produced by

Oligodendrocytes.

A myelinated axon can produce action potentials only in specialized regions called

Myelin sheath gaps.

The neurotransmitter secreted at an adrenergic synapse is

Norepinephrine.

Neurons cannot undergo mitosis to replace those that are lost, although

Limited replacement occurs via multiplication and differentiation of stem cells.