Cells of the Nervous System - PSYC 2113

neurons

specialized cells that can send electrical and chemical signals

neuron membrane

separates the inside from the outside of the neuron, contains phospholipids and large protein structures

cytoplasm

liquid inside of a cell containing organelles and microtubules

organelles

specialized structures within a cell

adenosine triphosphate (ATP)

energy used in cellular operations

cell body (soma)

large part of a neuron that contains the nucleus and other organelles, dendrites and axons branch from the cell body

dendrites

parts of neuron that branch from the cell body, receive information from other neurons and send electrical information to the cell body

axon

part of the neuron that sends signals away from the cell body, can branch several times

dendritic spines

small protuberances along dendrites, often meet terminal boutons of axons from other neurons to form a synapse

axon hillock

where axon meets cell body, electrical signals begin at or just past this area

axon collaterals

branches in the axon

terminal branches

smaller branches at the end of axon collaterals

terminal boutons

terminal ends of axons that look like buttons, part of a synapse where neurotransmitters are released

synapse

where one neuron communicates with another

myelin

fatty substance that surrounds axons, created by glial cells and helps insulate axons and increases the speed at which a neuron sends a signal

nodes of Ranvier

spaces scattered down an axon that do not have myelin

vesicles

balloon-like structures within a neuron that hold and release neurotransmitters

neurotransmitters

chemical messengers that are released at the terminal boutons of one neuron and affect receptors of another neuron

sensory (afferent) neuron

brings info toward the central nervous system (brain and spinal cord)

motor (efferent) neuron

brings info away from the central nervous system to muscles and glands

reflex arc

connection between a sensory nerve and motor neuron with the help of interneurons in the spinal cord, create a fast reaction to external stimuli

glial cells (neuroglia)

neuron support cells in the central and peripheral nervous system

astrocytes

star-shaped glial cell found in the central nervous system that serves many supporting functions for neurons, like providing oxygen and nutrients, repairing damage, and helping neurons communicate

oligodendrocytes

glial cells in the central nervous system that provide myelin to neurons

microglia

any of several types of small glial cells that serve functions in immunity and clear out unused synapses

Schwann cells

glial cells in peripheral nervous system that create myelin for neurons, several needed to provide myelin for one neuron