ANATOMY OF SOMATIC NERVOUS SYSTEM Flashcards
What does the EFFERENT nervous system do?
Carries information away from the CNS to the effectors- it is a motor system
What does the AFFERENT nervous system do?
Carries information from the periphery to the CNS - it is a sensory system
Which cells make up the nervous system and in what proportions?
- Neurones - 10%
- Glial cells - 90%
Glial cells assist neurones in their functions
What are the 3 types of neurones?
Draw them
- Motor
- Bipolar (special sense)
- Pseudo Unipolar
What are the 4 types of glial cells?
- Astrocytes - most common
- Oligodendrocytes
- Microglia
- Ependymal
What is the function of an astrocyte?
- Maintain synapses by removing old ones
- Provide structural and metabolic support
Function of an oligodendrocyte?
- Myelinates axons in the CNS - allows for saltatory conduction
- Metabolic and structural support - provide nutrients
Function of microglia? (3)
- Prevent pathogens going to the CNS
- Immune cells
- maintain homeostasis
Function of Ependymal?
- CSF synthesis
- Ciliated cells that regulate the flow of CSF
Describe the structure of ependymal cells
Small ciliated epithelial cells
Which cells myelinated axons in the PNS?
Schwann cells - only one axon at a time
Where are the afferent sensory cell bodies found?
Dorsal root ganglion
Whivh muscle types are effectors of somatic and autonomic systems?
Somatic - skeletal muscle
Autonomic - Cardiac or smooth muscle
What is a nerve made from?
Multiple neurones/ axons bundled together form a fascicle. Bundles of fascicles form a nerve.
What are the
- Endoneurium
- Perineurium
- Epineurium
Connective tissue that holds together;
- Bundles of axons
- Entire fascicle
- Multiple fascicle
What happens if there is disregulation in the microglia
It can lead to neurological disease
What can happen if there is defective or unregulated CSF flow?
There will be problems in the flow of CSF which can result in the accumulation of excess CSF which can lead to increased pressure
Where is the CSF located?
Within ventricles which are spaces
Where are the efferent cell bodies located?
Ventral root
