suporting cells Glia

Question 1

glia

Answer 1

Neuroglia are supporting cells in the central nervous system.

Their main roles are to:

Support neurons

Protect neurons

Insulate neurons

Maintain the environment around neurons (like keeping the chemical balance right)

Hold the nervous tissue together — that’s why they’re called “nerve glue” glia doesnt do electrical impulses

Question 2

astrocytes

Answer 2

Anchor neurons to blood capillaries

Their projections cling to neurons and capillaries, holding everything in place.

Form a barrier between blood and neurons

This helps protect neurons from harmful substances in the blood.

They help control what passes from the blood into the brain — part of the blood-brain barrier.

Regulate the brain’s chemical environment

“Mop up” excess potassium ions (K⁺) to keep electrical activity balanced.

Recapture neurotransmitters (chemicals used for neuron communication) after they’re used.

Question 3

microlia

Answer 3

spiderlike phagocytes that monitor the health of nearby neurons and dispose of debris, such as dead brain cells and bacteria

Question 4

ependymal

Answer 4

They help make cerebrospinal fluid (CSF)

Their cilia (tiny hair-like structures) circulate the CSF through the brain cavities (ventricles) and spinal cord cavity

🧠 Why is this important?
CSF forms a watery cushion that:

Protects the brain and spinal cord

Prevents friction by keeping the brain and spinal cord floating and cushioned

Helps remove waste and deliver nutrients

Question 5

Oligodendrocytes

Answer 5

Function:

Create myelin sheaths — fatty coverings that wrap around nerve fibers in the central nervous system (CNS)

Structure:

They have flat extensions (called processes) that reach out and wrap tightly around multiple CNS axons

Why it matters:

Myelin sheaths insulate the nerve fibers

This increases the speed of electrical impulses along neurons

Think of it like insulation on electrical wires — it helps signals travel faster and cleaner

Question 6

neuroglia facts

Answer 6

Although neuroglia somewhat resemble neurons structurally (both cell types have cell extensions), they are not able to transmit nerve impulses, a function that is highly developed in neurons. Another important difference is that neuroglia never lose their ability to divide, whereas most neurons do. Consequently, most brain tumors are gliomas, or tumors formed by neuroglia.

Question 7

satalite and schwan cell sonly glia in pns

Answer 7

Supporting cells in the PNS come in two major varieties—Schwann cells and satellite cells (Figure 7.3e). Schwann cells form the myelin sheaths around nerve fibers in the PNS. Satellite cells act as protective, cushioning cells for peripheral neuron cell bodies.