Neuro Ch 2

what are the two types of cells in the nervous system?

neurons and glia

what are neurons and what do they do?

they sense changes in the envt. and communicate to other neurons (command the body’s responses)

what are glial cells?

help insulate, support, and nourish neighboring neurons

holds our brain together (latin for glue)

what is histology?

microscopic study of the structure of tissues

what is a nissl stain?

class of basic dyes that stain the nuclei of all calls and material surrounding the nuclei of neurons

helped distinguish b/w neurons and glia

showed mainly neuron’s body (not full picture)

what is the golgi stain?

a silver chromate solution used to soak in brain tissue

allowed you to see the entire neuron

what are the parts of the neuron?

cell body (soma and perikaryon)

thin tubes radiating from soma (neurites) - these include axons and dendrites

what is the neuron doctrine?

stated that neurons are separate/individual cells that communicate with each other

went against reticular theory (neurons were joined together to form one continuous web)

what is the soma?

central/spherical part of the neuron

what is the cytosol?

watery fluid inside the cell

what are the organelles?

membrane-enclosed structures within the soma

what is the cytoplasm?

universal term for everything contained within the cell membrane except the nucleus

what is the nucleus?

spherical, centrally located within the soma

what are chromosomes?

contained within the nucleus and have DNA (genetic material)

what are genes?

segments of DNA used to assemble the cell

what is gene expression?

reading of the DNA

what are proteins?

the final product of gene expression

what is protein synthesis?

the assembly of protein molecules

what is transcription?

the process of assembling a piece of mRNA containing info of a gene

what is translation?

the process of assembling a chain of amino acids from mRNA

what is the mitochondria?

the powerhouse of the cell (gives you energy through ATP)

what is the axon hillock?

beginning region of the axon

what is the axon terminal/terminal buttons?

ending region of the axon

what is the axon proper?

the middle portion of the axon

what is the synapse?

the point of contact where the axon comes in contact with other neurons and pastes information to them

what are the two sides of the synapse?

presynaptic and postsynaptic

what is the presynaptic side?

usually the axon terminal

what is the postsynaptic side?

usually the soma/dendrite of another neuron

what is a neurotransmitter?

chemical signal that undergoes an electric to chemical to electric transformation of information

what is axon collaterals?

the places where the axons branch off

what are the dendrites?

receive information from axon terminals

what are receptors?

specialized protein molecules that detect the neurotransmitters in the synaptic cleft

what are dendritic spines?

structures that hang off the dendrite that receive synaptic input

how are neurons classified?

based on neuronal structure
based on gene expression

how are neurons classified based on neuronal structure?

1. # of neurites (axons and dendrites) extending from the soma

2. dendrites

3. connections

4. axon length

how are neurons classified base on gene expression?

glia

what are unipolar, bipolar, and multipolar neurons?

unipolar = one neurite

bipolar = two neurites

multipolar = 3+ neurites

what are stellate cells?

star shaped

what are pyramidal cells?

pyramid shaped

what are spiny/aspinous dendrites?

dendrites with or without spines

what are primary sensory neurons?

neurons with neurites in the sensory surfaces of the body

what are motor neurons?

neurons with axons that form synpases with muscles and command movements

what are interneurons?

neurons that form connections with other neurons

what are astrocytes?

star-shaped and fill spaces between most neurons (CNS)

what are oligodendroglial cells?

type of myelinating glia

proivdes myelin/insulate neurons to speed up signaling

for CNS

what are schwann cells?

type of myelinating glia

digest debris/guides growth

for PNS

what is the node of ranvier?

short length where the axonal membrane is exposed

this is where the action potential jumps from

what are microglia?

immune-like cells that remove waste products/damaged cells