Glial Cells in the Nervous System

Flashcards about Glial Cells

Glial Cells

Support cells in the nervous system that surround neurons and help them function.

Glial Cells Origin

From the Greek word for 'glue', initially thought to hold neurons together.

Glial Cells Quantity

More glial cells than neurons in the brain.

Glial Cells Function

Support and hold neurons in place, provide nourishment, insulate neurons electrically, and protect from pathogens.

Astrocytes

Star-shaped glial cells in the central nervous system that support and protect neurons by creating the blood-brain barrier.

Astrocyte Primary Role

Support and protect neurons and create blood brain barrier.

Astrocyte Location

Only exist in Central Nervous System.

Blood Brain Barrier

Protects the brain from toxins and poisons in the blood, formed by astrocytes and tightly bound endothelial cells.

Reactive Astrocyte

Reactive astrocyte changes nature in response to damage or inflammatory signal.

Schwann Cells

Glial cells in the peripheral nervous system that produce myelin to insulate axons, increasing the rate of conductance.

Location of Schwann Cells

Peripheral nervous system only

Myelin Sheath

Increases the rate of conductance and gives a characteristic white appaerance to the glial cell.

Nodes of Ranvier

Gaps between Schwann cells on an axon where impulses jump during saltatory conduction.

Saltatory Conduction

The process by which impulses jump between nodes of Ranvier, increasing the speed of electrical conductance.

Oligodendrocytes

Glial cells in the central nervous system that produce myelin for multiple axons.

Oligodendrocytes Function

Myelin production in the central nervous system

Multiple Sclerosis

Immune-mediated destruction of the myelin sheath, compromising nerve conduction speed and accuracy.

Microglia

Smallest glial cells that perform an immune function by scavenging debris and pathogens in the central nervous system.

Microglia Function

Immune defense of Central Nervous System by acting as phagocytes

Glial Scar

Physical barrier formed by reactive astrocytes after injury, preventing axon regrowth in the central nervous system.