Flashcards in Lecture 36 Deck (18)
characteristics of the dura mater
most outer covering
dense connective tissue
in the cranium forms the dural venous sinuses
characteristics of the arachnoid mater
Loose connective tissue
lined back to back by simple squamous epithelium
projects into the sinus to drain CSF into the blood stream
Characteristics of the pia mater
vascular loose connective tissue
Lies directly on the brain and spinal cord
interacts with ependymal cells to form choroid plexus
what kind of cells are found in the anterior gray horn?
alpha motor neurons cell bodies
posterior grey horn?
central segment of sensory neurons
lateral gray horn?
the cell bodies of visceral neurons
gray matter around a central canal
What does the central canal contain?
what do alpha motor neurons look like?
they are large cells with pale staining of large nuclei
have abundant nissl bodies
embedded in neuropil
What is the neuropil?
meshwork of tissue in gray matter excluding the cell bodies
Comprised of- dendritic and axonal processes, and central glial cells
What are the six layers of the cerebrum?
1. the molecular layer
2. external granular layer
3. external pyramidal cell layer
4. internal granular layer
5. ganglionic layer (internal pyramidal cells)
6. multiform cell layer (polymorphic)
What are the three layers of the cerebellum?
1. molecular layer (stellate and basket cells)
2. purkinje cell layer (single layer of motor neurons)
3. granular layer (granule cells and type II golgi cells)
What do granule cells do?
They carry excitatory signals to the cerebellum
What is the choroid plexus?
Invaginated folds of pia mater containing tufts of fenestrated capillaries covered by simple cuboidal ependymal cell in ventricles of the brain
What makes up the BBB?
1. continuous capillaries with tight junctions
2. the foot processes of astrocytes (surround the capillaries and neurons
3. neuronal processes (mostly astrocytes)
what the epineurium?
outer most tissue of a peripheral nerve
typically dense CT
carry blood to the nerves
what is the perineurium?
surrounds the bundles of nerve fibers
cells joined by tight junction
has contractile properties