nervous tissue: 2 types of cells

Question 1

neurons are…

Answer 1

excitable nerve cells that transmit electrical signals

Question 2

supporting cells are…

Answer 2

smaller cells surrounding and wrapping neurons

“neuroglia”

Question 3

neuroglia

also known as “?”, how many types of small cells are associated with neurons? what are its functions? what does it separate and protect? what does it regulate? what does it repair? what does it supply? what does it perform?

Answer 3

“nerve glue”
6 types of small cells associated with neurons- 4 in CNS, 2 in PNS
separate and protect neurons
regulate composition of interstitial fluid between neurons
repair neurons after injury
supply nutrients to neurons
perform phagocytosis ~ clean up

Question 4

types of neuroglia

CNS neuroglia and PNS neuroglia

Answer 4

central nervous system (CNS):
ependymal cells, oligodendrocytes, astrocytes, microglia

peripheral nervous system (PNS): satellite cells, schwann cells

Question 5

what types of neuroglia are found in the central nervous system?

Answer 5

astrocytes, microglia, ependymal cells, oligodendrocytes

Question 6

what types of neuroglia is found in the peripheral nervous system?

Answer 6

satellite cells, schwann cells

Question 7

CNS neuroglia

astrocytes

astrocytes are the most what cells, anchoring what to blood supply?astrocytes guide what of young neurons? astrocytes facilitate what to neurons? astrocytes control what around neurons? astrocytes form after what?

Answer 7

most abundant and versatile glial cells

numerous processes support branching neurons
-anchor neurons to capillary blood supply

guide migration of young neurons

facilitate nutrient delivery to neurons (blood, glial cell, neuron)

controls chemical environment around neurons
-uptake of K+, neurotransmitters

form scar tissue after injury

Question 8

cns neuroglia

microglia

small what cells? relatively what processes? processes touch what neurons?
migrates towards? transforms into? phagocytizes and removes? can cells of immune system enter CNS?

Answer 8

small ovoid cells

relatively long “thorny” processes
-processes touch nearby neurons

migrate toward injured neurons

transform into macrophage

• phagocytize microorganisms, removes cell debris
• cells of immune system cannot enter the CNS

Question 9

cns neuroglia

ependymal cells

lines what cavities? forms what barrier between what? produces and secretes? shapes what? many are what?

Answer 9

lines central cavities of brain and spinal cord

• form permeable barrier between cerebrospinal fluid inside these cavities and tissue fluid of CNS tissue
• produces and secretes cerebrospinal fluid ~ CSF

shapes range from squamous to columnar

many are ciliated
-beating helps circulate cerebrospinal fluid cushioning bran and spinal cord

Question 10

cns neuroglia

oligodendrocytes

are there fewer processes than astrocytes? myelination of what? what is myelin? insulates cells from? increases speed of what? myelin gives myelinated axons what known as? myelin sheath is?

Answer 10

fewer processes than astrocytes
myelination of CNS neurons and axons

myelin ~ membrane wrapping around nerve fibers

insulates cells from interstitial fluids

myelin gives myelinated axons “white color”

“white matter”

myelin sheath ~ entire axon covered by myelin

Question 11

pns neuroglia

satellite cells

surrounds what cell bodies within? what is a ganglion? functions?

Answer 11

• surround neuron cell bodies within ganglia
• a ganglion is a collection of nerve cell bodies outside of the CNS

*functions poorly understood