Nervous Tissue 15 Flashcards
What does the Central Nervous System (CNS) consis of
brain and spinal cord
What does the Peripheral nervous system consist of
- consists of cranial and spinal nerves that contain both sensory and motor fibers
- connects CNS to the muscles, glands & all sensory receptors
Dermatome
cutaneous area developed from one embryonei spinal cord segment and recieving most of its sensory innervation from one spinal nerve.
Myotome
group of muscle sinnervated by the motor neruons of a single spinal segment
motor neuron
neurons that conduct impulses from th ebrain toward the psinal cord or out of the brain and spinal cord into cranial or spial nerves to effectors that may be wither muscles of glands. Asl known as efferent neurons
How many pairs of cranial nerves
12
how many pairs of spinal nerves emerge from the spinal cord
31
Ganglia
n(located outside the brain and spinal cord), are small masses of nervous tissue, containing primarily cell bodies of neurons.
Plexuses
nPlexuses crossing over of nerves to backup function e.g. Enteric plexuses help regulate the digestive system.
Sensory receptors
nSensory receptors are either parts of neurons or specialized cells that monitor changes in the internal or external environment.
How many pairs of cranial nerves exit in the cervial
8
How are the nerves named
from the vertebrae that they exit
Describe what the sensory function of nerves mean
nSensory function: to detect changes in the internal and external environment through specialized receptors.
qSensory (afferent) neurons (nerve cells) serve this function.
afferent
sensory
efferent
motor
What are beroreceptors
the mech by which we have a feedback loop for blood pressure
What purpose do interneurons serve
nIntegrative function: to analyze the sensory information, store some aspects, and make decisions regarding appropriate behaviors.
qAssociation or interneurons serve this function.
______________ is to respond to stimuli by initiating action.
motor function
What is the functional unit of the nervous system
neuron
define slow axonal transport
movement of materials from the cell body to the axon terminals
- movement in one direction only – away from cell body
- movement at 1-5 mm per day
define fast axonal flow
- moves organelles & materials along surface of microtubules
- at 200-400 mm per day
- transports in either direction
- for use or for recycling in cell body
Purkinji cell
cell shape- highly branching dendrites
in cerebellum
Pyramidal cells
found in the cerebral cortex
pyramid chaped cell bodies
What is the most coomon type of cell found in the CNS
neuroglia
