Nervous System Pt 1 Flashcards
Nerves associated with the brain stem are known as
Cranial nerves
What is a multipolar neuron? Pseudounipolar? Bipolar? Where are they found?
Mutlipolar neuron has MANY dendrites and a single axon, pseudounipolar looks like it has one dendrite, bipolar has 2 dendrites.
Multipolar- motor (anterior- ventral)
Psuedounipolar- sensory (posterior- dorsal)
Bipolar- hearing
The nervous system is split into 2 parts:
Central (CNS- Within skull and vertebral column) and Peripheral (PNS- Outside of the CNS)
What does the cerebral hemisphere consist of?
the cerebrum - use to think
diencephalon (thalamus, hypothalamus, epithalamus, subthalamus)
What does the brain stem consist of? What does it turn into?
The midbrain, pons and medulla –> turns into the spinal cord
What is located posterior to the brain stem?
The cerebellum
The peripheral nervous system consists of 2 types of nerves:
Spinal nerves and cranial nerves- by definition these are outside of the CNS
How many cervical nerves are there? Thoracic? Lumbar? Sacral? Coccygeal?
8 cervical nerves but only vertebrae! How? First comes out above C1. 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal nerve.
What are cranial nerves 1 and 2 associated with?
The cerebral hemisphere`
What are cranial nerves 3-10 and 12 associated with?
The brain stem
What is cranial nerve 11 associated with?
The upper spinal cord (accessory nerve)
What are spinal nerves associated with?
The spinal cord
What is a ganglia? What are the two types?
A collection of nerve cell bodies associated with PERIPHERAL nerves and located OUTSIDE the CNS. Sensory (spinal nerve and cranial nerve ganglia) and motor (sympathetic ganglia and parasympathetic ganglia).
Describe the pathway of a sensory ganglia?
Stimulus comes in (hand on iron) through a mixed spinal nerve to the ganglia (OUTSIDE the CNS) this 1st order nerve sends a message through the dorsal horn and to CNS. Takes signal and makes motor function out of anterior horn down a multipolar neuron.
What does autonomic mean? What organs does it supply?
“Automatic” or visceral because they supply the viscera aka the heart, lungs, GI tract, urinary bladder etc. everything inside
Where is an autonomic nerve cell body found? What kind of nerves?
Autonomic nerve cell bodies are located in motor or visceral ganglia found OUTSIDE the CNS (along the vertebral body in the diagrams). There are multipolar nerves.
How many neurons pass from the CNS to the organ of innervation?
2, a pre-ganglionic and post-ganglionic neuron
Describe the cervical spinal cord
Oval shape, due to large ventral horns which provide motor function to the upper limbs- lots of gray and white matter.
Describe the thoracic spinal cord
Very circular in shape, small ventral horn because not a lot of motor function. Progressively less white matter.
Describe the lumbar spinal cord
Circular in shape with lots of gray matter due to large ventral horns which supply motor functions to the legs. Progressively less white matter.
Where are the lateral horns present? What is their function?
The lateral horns are present in the thoracic and lumbar vertebrae (to L2) these are the PREganglionic cell bodies or the sympathetic nervous system!
What are the stripes in the white matter called? What is their functions?
These are called dorsal/lateral/ventral columns or funiculus. They are myelinated nerve fibers that run through the cord.
What does the gray matter consist of? What type of nerve are they?
Nerve cell bodies and their processes- all gray matter is MULTIPOLAR
Where are first order sensory neurons? Where are secondary order?
First order are the dorsal root ganglion, second order are in the dorsal horn
