histology peripheral nervous system

schwann cells

in the PNS, axons are sheathed by _________

a group of axons

what is a fascicle?

nerve

multiple fascicles make up a _____

PNS- elongated nuclei, schwann cells

is 1 the CNS or PNS?

2- lines of oligodendrocytes

which one is the CNS?

nerves

nerve ganglia

sensory nerve terminals

what are the 3 main components of the PNS?

axons + nuclei + conjunctive tissue

nerves are composed of ______

fibers carrying impulses to the CNS

what are sensory nerves?

motor nerves

fibers carrying impulses to effector organs are called...

epineurium- covers nerve, dense CT

perineurium- covers fascicles, dense CT

endoneurium- covers axons, loose CT

what are the 3 different conjunctive tissues of a nerve?

epineurium

what is the type of conjunctive tissue that covers nerves?

conjunctive tissue that ensheathes fascicles

what is perineurium?

endoneurium

what is the type of conjunctive tissue that covers axons?

fascicles

what are these?

groups of axons

what are fascicles?

perineurium/perineurial epithelium

what is this thin layer surrounding the fascicles?

perineurium

the red arrows show what?

perineurial epithelium

what do the green arrows point to?

fibroblasts connects with tight junctions for transport control

the perineurial epithelium is made up of...

perineurium

what is P?

perineurial epithelium

what is PE?

endoneurium

what is e?

axon

each star represents a ...

circular formations of fibroblasts

if a patient has a neurofibrosarcoma, what is the histological appearance?

neurofibrosarcoma- circular formations of fibroblasts

what disease is represented by these histological pictures?

aggregations of neuronal cell bodies outside of the CNS

what are nerve ganglia?

nerve ganglia

aggregations of neuronal cell bodies in the PNS are called...

spinal/dorsal root ganglia

autonomic/sympathetic ganglia

what are the 2 types of nerve ganglia we see in the PNS?

-CT capsule

-axons+neuronal bodies (in spinal ganglia- pseudounipolar, and in autonomic ganglia- multipolar)

-schwann+ satellite cells

what are the components of nerve ganglia?

pseudounipolar

what type of neurons do we have in spinal ganglia?

spinal ganglia (aka dorsal root ganglia)

big cell body, central nucleus, no synapses

what is this a section of?

autonomic ganglia

which- spinal or autonomic ganglia has synapses?

autonomic

in ______ ganglia, there are synapses made from pre and post ganglion neurons

a neuron with its body in the CNS, but travelling towards the autonomic ganglia

what is a preganglion?

a neuron with its body in the autonomic ganglia, travelling towards the effector organ

what is a postganglion?

not always

do sensory nerve terminals have a CT capsule?

tactile stimuli (meissner's corpuscles)

vibration detection (pacini corpuscles)

sensory nerve terminals with a CT capsule (corpuscles) are for what purpose?

corpuscle

a combination of sensory nerve terminals and a capsule is called a...

nerve terminal branches + CT capsule

what is a corpuscle?

heat, cold, pain

sensory nerve terminals without a CT capsule are for what sensations?

Pacini corpuscle- nerve terminal+CT capsule, for vibration detection

what is this?

Meissner's corpuscles- nerve terminal+ CT capsule, for tactile sensation

what is this?

not encapsulated

are nerve terminals that detect heat, cold, and pain encapsulated or not?

Pacini corpuscle- nerve terminal+CT capsule, for vibration detection

what is this?

meissner's corpuscles

which type of corpuscle is for tactile stimuli?

pacini corpuscles

which type of corpuscle is for vibration stimuli?