### cell | vegetative cell:

Glial cell
* Some glial cells produce an insulating material called myelin.
* act in interesting ways to modulate the survival and growth of neurons.
* are a specific type of brain cell
  - astrocytes, oligodendroglia, ependymal cells, and microglia
  - considered support cells, only secondarily involved in signaling and integration
  - more numerous than nerve cells
  - non-neural support cells and are of three, functionally distinct types
  - non-neuronal cells which play supporting roles in the brain and nervous system
* are responsible for making up the blood brain barrier
  - the most aggressive type of brain tumor, the glioblastoma
  - the metabolic and structural support cells for the nerve cells
* are the most common cellular component of the brain
  - numerous calls in the brain
* can divide by mitosis and hence get rejuvenated
  - in response to damage, creating a glial scar
* carry out metabolic functions in the nervous system.
* contribute to the formation of subretinal membranes.
* help wrap axons to enhance propagation of electrical signals.
* immigrating from the optic stalk take residence in the basal layer of the eye disc.
* increase in number when nerve cells grow with enrichment.
* multiply dramatically from fetal age four months to the child's second birthday.
* perform critical functions in the nervous system.
* play a crucial role in immunological responses to various infections and toxic agents.
* produce myelin, which fatty substance that protects the nerves.
* provide nutritional, metabolic, and mechanical support to neural tissue
  - scaffolding
  - support for neuronal function
* serve a variety of functions depending upon their specialization.
* support and nourish the neurons.
* support the neurons in many ways
* surround and support the neurons.

### cell | vegetative cell | glial cell:

Astrocyte
* also take up various extracellular ions.
* are accessory cells found in the nervous system
  - also important for maintaining proper ionic balance in the extracellular fluid
  - important for regulation of metabolic activities of neurons
  - key players in the cellular response to injury in the nervous system
  - star-shaped cells that provide the scaffolding upon which neurons can grow
  - the most plentiful and diverse of the glial cells
* can take up neurotransmitters, and even possess neurotransmitter receptors.
* contain many intermediate filaments suggesting they provide structural support.
* create the blood-brain barrier that keeps unwanted substances out of the brain tissue.
* express functional chemokine receptors.
* form scar tissue in the form of astoglial fibers.
* generate isoprostanes in response to trauma or oxygen radicals.
* have a complex morphology with numerous fine processes that ensheath synapses
  - elaborate processes that extend between blood vessels and neurons
  - numerous filaments within their cell bodies and processes
  - other functions
* participate in maintenance of brain homeostasis and disease pathogenesis.
* play a central role in maintaining brain homeostasis.
* represent the most abundant cell type of the adult nervous system.
* then cause the toxic effects on the motor neurons.