Neurons First Test Flashcards
neuron
sense changes in brain environment, communicate changes to other neurons, and commands body’s responses to changes
excitable
amitotic
glial cell
insulate, support, and nourish neurons glue non excitable 10x more numerous than neurons mitotic
histology
the microscopic study of the structure of tissues
nissl stain
a class of basic dyes that stains the nucleus of all cells and also stains clumps of material surrounding the nuclei of neurons distinguishes neurons and glia from one another enables histologists to study arrangement of neurons in different parts of the brain
cytoarchitecture
the arrangement of neurons in different parts of the brain
study of cytoarchitecture led to realization that brain consists of many specialized regions
golgi stain
golgi soak brain tissue in silver chromate solution
small percentage of neurons become darkly colored in entirety
revealed that neuronal cell body (region of neuron around the nucleus that is shown with the nissl stain) is only small fraction of total structure of neuron
cell body
swollen region containing organelles and cell nucleus
aka soma aka perikaryon
neurite
the thin tubes that radiate away from the soma
two types: axons and dendrites
axon
wires that carry the output of the neurons
dendrite
come in contact with axons
act as antennae of neuron to receive incoming signals or input
neuron doctrine
the idea that the neuron adhered to the cell theory
golgi said neurons continuous, cajal said neurites of different neurons are not continuous and communicate by contact not continuity
canal/neuron doctrine correct
cytosol
the watery fluid inside the cell
contanis organelles
organelle
membrane-enclosed structures inside the cell
cytoplasm
everything contained within the confines of the cell membrane, including the organelles but excluding the nucleus
nucleus
spherical, centrally located
contained within nuclear envelope
contains DNA and genetic material for the cell
chromosome
contain genetic material DNA
double strands
DNA
genetic material passed on by parents
codes for identity
huge amount
gene
segments of DNA that code for specific parts of identity
gene expression
the reading of the DNA
final product of this is the synthesis of proteins
the process by which information from a gene is used in the synthesis of a functional gene product
protein
exist in a wide variety of shapes and sizes, perform many different functions, and bestow upon neurons virtually all of their unique characteristics
protein synthesis
assembly of protein molecules
occurs in cytoplasm
mRNA
the intermediary that carries the genetic message to the sites of protein synthesis in the cytoplasm
consists of four different nucleic acids strung together in various sequences to form a chain
detailed sequence of nucleic acids represents the information in the gene
transcription
process of assembling mRNA from DNA
occurs in nucleus
microglial cell
function as phagocytes to remove debris left by dead or degenerating neurons and glia
translation
assembling of proteins from amino acids under direction mRNA
occurs in cytoplasm
ribosome
take raw material in the form of amino acids and manufacture proteins using the blueprint provided by the mRNA
attached to rough ER and free
rough go into membranes
proteins synthesized on free ribosomes are destined to reside within the cytosol of the neuron