Cells, neurons, glia
Neurons
Main units of nervous system
same characteristics as normal cells
Made up of aqueous cytoplasm (gel surrounding membrane)
bounded by cell membrane ( plasma membrane or lipid membrane)
consists if sheet of several individual molecules
made up of two hydrophobic (water fearing) tails & 1 hydrophilic
(water loving) tail
Very effective in keeping charged molecules & ions out while letting
small molecules like oxygen and water in
Organelles
About 86 billion neurons within the adult human brain
counted by isotropic fractionator
Neurons are electroactive
membrane potential or Transmembrane potential: The difference between the
negatively charged cell and the positively charged solution surrounding the
cell
At rest a neuron typically has a -70 charge, when active can go to +45 and
back to -70 within 2 milliseconds
Cells within the heart can also do this change in charge, hence why a
defibrillator can shock a heart back into starting
Rapid communication
all cells can have rapid communication electorally, neurons are specifically
made to have very fast communication both electorally and chemically.
Cells, neurons, glia 1
, Neurons are “forever cells”
Body is constantly making and replacing old cells (skin cells monthy ect)
Neurons that are there when the brain is fully developed tend to be the
neurons people die with
Neurons can change
Plasticity: the ability for the brain to alter its morphology (connection? Purpose
between two neurons)
the brain can go through periods of hightened plasticity where neurons
may take on the job of damaged ones, changing the way it works iwthin
the brain
Neurons can repair themselves to an extent
Can regrow and attach to where it originally was
Can be very slowly
typically happens to neurons within the cns in the spinal cord that ger
damaged when trauma happens to the body
Dendrites
where information first enters the cell
branch like extensions from the cell
have “spines”: Tiny bumps that stick out along the dendrite, where chemical
information is recieved & reason for ability to learn new facts
can have 6 shapes, come from changes with exposure to different drugs,
chemicals
Cell Body (soma)
filters information
contains many of the main organelles
nucleus most visible
Cells, neurons, glia 2
Neurons
Main units of nervous system
same characteristics as normal cells
Made up of aqueous cytoplasm (gel surrounding membrane)
bounded by cell membrane ( plasma membrane or lipid membrane)
consists if sheet of several individual molecules
made up of two hydrophobic (water fearing) tails & 1 hydrophilic
(water loving) tail
Very effective in keeping charged molecules & ions out while letting
small molecules like oxygen and water in
Organelles
About 86 billion neurons within the adult human brain
counted by isotropic fractionator
Neurons are electroactive
membrane potential or Transmembrane potential: The difference between the
negatively charged cell and the positively charged solution surrounding the
cell
At rest a neuron typically has a -70 charge, when active can go to +45 and
back to -70 within 2 milliseconds
Cells within the heart can also do this change in charge, hence why a
defibrillator can shock a heart back into starting
Rapid communication
all cells can have rapid communication electorally, neurons are specifically
made to have very fast communication both electorally and chemically.
Cells, neurons, glia 1
, Neurons are “forever cells”
Body is constantly making and replacing old cells (skin cells monthy ect)
Neurons that are there when the brain is fully developed tend to be the
neurons people die with
Neurons can change
Plasticity: the ability for the brain to alter its morphology (connection? Purpose
between two neurons)
the brain can go through periods of hightened plasticity where neurons
may take on the job of damaged ones, changing the way it works iwthin
the brain
Neurons can repair themselves to an extent
Can regrow and attach to where it originally was
Can be very slowly
typically happens to neurons within the cns in the spinal cord that ger
damaged when trauma happens to the body
Dendrites
where information first enters the cell
branch like extensions from the cell
have “spines”: Tiny bumps that stick out along the dendrite, where chemical
information is recieved & reason for ability to learn new facts
can have 6 shapes, come from changes with exposure to different drugs,
chemicals
Cell Body (soma)
filters information
contains many of the main organelles
nucleus most visible
Cells, neurons, glia 2
