Histology - Neural Tissue Flashcards
Identify the Green and Red Arrows
Green Arrow = Nerve Endings
Red Arrow = Spinal Ganglia
What are glial Cells?
Support cells that are found throughout the nervous system
Identify the purple and orange arrows
Purple Arrows = Axons and Long Dendrites
Orange Arrows = Neuronal Cell Bodies
What are the two major regions of the spinal
cord?
Gray Matter = Neuronal Cell Bodies
White Matter = Axons and long dendrites
What are multipolar neurons?
Neurons with an axon and several dendrites
e.g. Motor Neurons of the peripheral nervous system
Identify the structures indicated by the arrows
Neuronal Cell Bodies
Identify the structures indicated by the green and red arrows.
Green Arrows = Multipolar Motorneuron Cell Bodies
Red Arrows = Oligodendrocytes, Non-Neuronal Cells (Smaller round nuclei)
Identify the structures indicated by the green, black, yellow, and red arrows
Also Identify Nissl Bodies
Green Arrows = Dendrites
Black Arrow = Delimitation of the Nucleus
Yellow Arrow = Nucleolus of a Nueron (abdunant euchromatin)
Red Arrows = Glial Cells
Nissl Bodies are the puple flaky weblike parts which also
comprise dendrites
What is a perikaryon?
Cytoplasm of neuronal cell body
What are Nissl substances/Nissl bodies
Clusters of rough endoplasmic reticulum in the cytoplasm of neurons.
Identify the structures indicated by the arrows and the outlined regions
Arrow = Axon
Outlined Region = Hillux of the Axon
Important = Axons Lack Nissl Substance (Dendrites
contain Nissl Substance)
What does this image depict?
Identify Structures A through D
Cell body of a motor neuron
A = Nissl Substance
B = Euchromatic Nucleus
C = Nucleolus
D = Capillary
Identify structures indicated by A and B
A = Mitochondria
B = Nissl Bodies
Identify the Areas indicated by the blue box
White matter of the spinal cord (oriented cranial caudally) contains mylenated axons and some dendrites and is sending information up and down the spinal cord.
What time of staining was used?
Identify the structure indicated by the yellow arrow and the pale region surrounding the structure indicated by the yellow arrow.
Section was labeled with a silver stain
Yellow Arrow = Axon
Pale Region = Myelin
Identify the structures indicated by/between the yellow arrows.
Myelin
Identify the outlined regions
Outlined Regions = Locations where nerves can be found
Important = Neuronal Cell Bodies are NOT found in nerves
Enseathment
During embryogenesis schwann cells initially surround several axons with their cytoplasm and plasma membrane
Smaller caliber axons remain enseathed
What happens to large axons after embryogenesis?
Schwann cell selects a single axon to support and wraps its cytoplasm and plasma membrane around the axon several times. When the cytoplasm is squeezed out the remaining layer of shcwann cell membrane is called myelin
Myelin
A region of axon that is wrapped with several Schwann cells
A single axon is myelinated by several schwann cells
Nodes of Ranvier
Regions of bare axon not surrounded by myelin
Identify the structures indicated by the letter A and the purple, red, and green arrows and the areas outlined in blue.
A = Schwann Cell Cytoplasm
Red Arrows = Gaps in the Schwann Cells which show they wrap around axons
Purple Arrows = Schwann cell plasma membrane and it’s external Lamina
Green Arrows = Two plasma membrans of axon and schwann cell
Blue Outline = Collagen (Reticular) Fibers
Identify the structures indicated by the arrows
Blue Arrow = External Lamina
Purple Arrow = Many membrane layers of a single Schwann Cell
Yellow Arrow = Axonal Membrane
Red Arrow = Microtubules
Green Arrow = Neurofilaments (Intermediate Filaments)
Identify the stain used and the structure indicated by the arrow.
Osmium tetroxide which labels myelin membrane
Arrow indicates nodes of ranvier
Identify the view in the top portion of the image as
compared to the bottom portion.
Identify the structures indicated by the blue arrow as compared to the green arrows
Top portion is cross-sectional view of the axon
Bottom portion = longitudinal view of the axon
Green Arrow = Axon
Blue Arrow = Edge of Myelin
Identify the structures indicated by the blue outlines
Rodes of Ranvier