Lec 2 Review of brain histology Flashcards
Where in the neuron does the action potential initiate?
the spike initiaion zone in the nerve cell body (soma) near the axon hillock
What are boutons?
swellings at the ends of axon terminal
What is a telodendron?
the entire array of terminals for one axonal process
What are neruonal processes?
non-specifically refer to axons and dendrites
What is structure of multipolar neurons?
- 3-5 primary dendrites coming off cell body
- axon emerges from axon hillock
Where do you find multipolar neurons?
through the CNS
What is structure of bipolar neurons?
- single process
- cell body located directly along the course
- distal extension is dendrite, proximal (directed toward CNS) is axon
Where do you find bipolar neruons?
- retina
- in clusers of cell bodies (ganglia) of vestibular and auditory cranial nerves
What is structure of unipolar neurons?
- single process extends proximally and distally from a short segment that connect it to the cell body
- both parts of process technically called neurites (or distal = dendrite, proximal = axon)
Where do you find unipolar neurons?
sensory ganglia in PNS
notably in dorsal root ganglia
What is structure of pyramidal cells?
- pear shaped soma, several dendrites
large, highly branched dendrite from apex of soma called apical dendrite
- axon from base of the cell body
- have dendritic spines
What is function of dendritic spines?
What are granule cells? structure?
- smaller, star shaped (stellate)
- dendritic tree radiates out in all directiosn from the soma
- provide much of local (regional) info processing)
What are the 3 different types of neurons as classified by length of axon?
- projection clels
- interneurons
- amacrine cells
What are projection cells?
- neurons with long axons
- axons extend long distance, send neural signal from one region of nervous system to another
- long axons sometimes branch into: 1. main axon that projects to chief target site, 2. axon collateral that projects to another far location
