Lecture 13: Histology of the CNS Flashcards
Describe the anatomy of a neuron
- Cell body: is large, w/ large nucleus and Nissl substance/bodies
- Numerous dendrites
- Long axons, emerges from axon hillock
Label A-D
A) Axon
B) Nissl bodies
C) Nucleolus
D) Nucleus
Where are Nissl bodies found and why can this help you histologically?
- Found only in cell body and dendrites of a neuron
- Can help you distinguish the axons from the dendrites
What type of neuron is this?
Pyramidal cell - Multipolar neuron
Label A-E on this neuron
A) Nissl substance
B) Nucleus
C) Axon Hillock
D) Axon
E) Dendrite
What are the 6 layers of cerebral cortex from superficial to deepest?
I: Molecular layer
II: External Granular layer
III: External Pyramidal layer
IV: Internal Granular layer
V: Internal Pyramidal layer
VI: Multiform layer
Where is the white matter and gray matter located within the Cerebral Cortex?
Gray matter: outer layer
White matter: inner layer
Identify the layers A-F of the cerebral cortex.
A) Molecular layer
B) External granular layer
C) External pyramidal layer
D) Internal granular layer
E) Internal pyramidal layer
F) Multiform layer
What strucutre is this and identify layers A-C
- Cerebellar cortex
A) Molecular layer
B) Granular layer
C) Cerebellar medulla (white matter)
Identify A-D
A) Molecular layer
B) Purkinje Cell Dendrites
C) Purkinje Cell Body
D) Granular Layer
*This is the cerebellar cortex
What are the 4 layers of the Cerebellar cortex from outermost to innermost?
1) Molecular Layer
2) Purkinje Cell Layer
3) Granular Layer
4) Cerebellar medulla (white matter)
Identify this cell type
Purkinje Cell
Identify this cell type
Purkinje cells
Identify A and B; what kind of synapse is this?
- Chemical synapse
A) Pre-synaptic terminal
B) Dendrite
Identify A-C
A) Presynaptic Membrane
B) Postsynaptic Membrane
C) Synaptic Cleft
Identify this cell type
Astrocyte
What is the function of Astrocytes?
- Branching expansions called End-Feet
- Helps form the blood-brain barrier
- Provide structural support and organization to the CNS
What does this picture show?
- Astrocytes connected to BV’s by their end-feet
- Producing the BBB
What is the main component of the blood brain barrier?
Tight junctions
What is the function of Oligodendrocytes and where do they act?
- Provides a myelin sheath to multiple axons!
- Schwann cells of the PNS can only myelinate one axon
Identify the structures
What is the function of Microglia?
- Migratory, will remove damaged or unactive synapses/other fibrous components (phagocytic cells of CNS)
- Major mechanism of immune defense in the CNS
Identify this cell type
Microglia
What are Ependymal Cells?
- Columnar or cuboidal cells that line fluid-filled ventricles of the brain and central canal of spinal cord
- Apical end may have cilia and long microvilli
Identify A and B?
A) Ependymal cells
B) Ventricle
Identify the arrows from top to bottom
Top: Dorsal Horn
Middle: Lateral Horn
Bottom: Ventral Horn
Identify A and B
A) Fasciculus Cuneatus
B) Fasciculus Gracillis
Identify A and B
A) Choroid Plexus
B) Ependymal Cells
