hms 1 Flashcards
what makes up the CNS
brain, spinal cord
what makes up the PNS
peripheral nerves
what are the 2 general cell classes in nervous tissue
neurons and glia
features of neurons
Specialised for transmission
many types of cells
many types of information
general function of glia
number of types
functions
support for neurons
five basic types (4 in CNS, 1 in PNS)
each types has specific function
5 types of glia and location
Astrocytes CNS Microglia CNS Ependymal cells CNS Oligodendrocytes CNS Schwann cells PNS
Features of Astrocytes
supply nutrients to neurons
ensheath blood capillaries
Transmit information (new)
Features of Microglia
immune cells of CNS
engulf microorganisms and debris
Features of Ependymal cells
fluid filled spaces of brain in spinal cord
have cilia to circulate CSF
Features of Oligodendrocytes
support central nerve fibres
ensheath them with myelin
Features of Schwann cells
support peripheral nerve fibres
ensheath them with myelin
Function of lipid fat myelin sheath
increases the conduction velocity
multiple sclerosis cause
autoimmune infection attacking myelin sheath causing impaired nerve conduction
structure of neurons zones and structures
input zone- dendrites and cell body receive chem signal
summation zone- axon hillock, decision
conduction zone- on carry electrical signals
output zone- axon terminals release NT
nodes of ranvier function
to increase conduction between schwann cells
