| Question |
Answer |
| 3 main features of a nueron |
Cell body (soma), axon, dendrite |
| What is a Lewey body |
Brown or yellow inclusions in the soma. Usually a sign of degenerative disease |
| 3 types of nuerons |
unipolar, multipolar, and pseundounipolar |
| Location of psuedounipolar |
dorsal root ganglion, SENSORY |
| Description/Location of Bipolar |
1 dendrite, one axon, used in ganglion for sensroy type signaling, found in Retina |
| Description/Location of Mulitpolar |
multiple dendrites feed to a single soma. These make up most nuerons and are found in the endo/excrine system, muscle, and ventral horns MOTOR |
| What is an ogliodendrocyte |
found in CNS, responsible for mylenation |
| Two types of transport in an axon |
Orthograde (from cell body to nerve endings) or retrograde (from nerve endings to cell body) |
| What type of transports does rabies utilize |
Retrograde |
| what is an astrocyte |
carry nutrients from cappilaries to the nueron, maintains ionic conditions, are mitotically active and form glial scarsAlso maintain blood brain barrier, and absorb/recycle nuerotransmitters |
| what is a microglia |
arise from monocytes, act as a phagocyte to remove waste and debris |
| What is a Ependymal cell |
line the brain and spinal cord. Assist in making and moving CSF, produce choroid process |
| What is a Schwann cell |
found in PNS, produces mylen and helps in repair after injury |
| What is a sattelite cell |
surround cell bodies in ganglia, PNS, regulates 02, CO2 and nutrients |
| what do schwann cells origniate from |
nueral crest cells |
| how do schwann cells mylenate |
wrap around the axon over and over again to |
| Name the three layers that make up the divisions of neurons (from outtermost to innermost) |
Epineurium, Parineurium, and Endoneurium |
| How many axons can a schwann cell mylenate |
many |
| What is a node of Ranvier |
a gap in the myelination. Has a high concentration of Na+ channels to regenerate the action potential |
| What are the two types of ganglia |
Dorsal Root Ganglia and ganglia of cranial nerves |
| type of tissue that surrounds sensory ganglia |
dense connective tissue |
| What are the three types of snesroy receptors in the integument |
Pacinian corpuscles, Meissners corpuslces, and intrafusal fibers/muscle spindles |
| Describe Pacini's corpuscles |
onion shaped, stimulated by pressure, vibration and tension in the deep layer of the skin, finger pads, tendons and ligaments around viscera |
| Describe Messner's corpuscles |
fine touch recpetors (mechanoreceptor) in dermis or finger pads. Look like 'tornado' or bee hive. Found in lips, gential skin and eyelids |
| Describe Intrafusal fibers/muscle spindles |
made of 3-12 fibers, responsible for contraction, monitor amount and rate of stretch |
| Cell types responsible for CNS tumors |
Glial cells |
| Can nerves in the PNS regenrate |
YES |
| what happens when a PNS nueron is cut |
cell membrane permiability increases, takes on water, nissel bodies disappear, and the end proximal to the nueron undegoes RETROGRADE DEGENERATION |
| What is it called when a axon in the PNS is cut and looses color |
chromatolysis |
| What is Wallerian Degeneration |
takes place in an axon distal to the cut. Terminal swells, myelen sheath breaks down and macrophages clean it up |
| Name the cell membrane of the axon |
axolemma |
| Name the cytoplasm of the axon |
axoplasm |
Ch.18 LTI-MA 509
