L13. Nervous System Flashcards
What is the CNS?
The CNS is a conveyor of information that can be divided or organized into different parts
What is a neuron
It is a specialized unique structure that transmits information ( in the CNS)
What are the functions of a neuron?
- stores information: learning
- memory
- coordinate body activities
- detect and analyze sensory information
Which embryonic layer is the neuron derived from?
It is derived from the ectoderm layer
What constitutes the CNS
brain , spinal cord
What constitutes the PNS
all the nerves in the body:
spinal, autonomic, enteric
Describe the information flow in the nervous system
sensory info (PNS)-> CNS (brain+spinal cord)-> PNS (neuron)
How can the Nervous system be divided into?
- diff regions dedicated to diff parts of the body
- diff regions serving diff modes or information
- somatotopic organization
What is a sematotopic organization
- consists of bumps of gyri ( provide greater SA for increased motor function
a. precentral gyrus
b.postcentral gyrus - grooves known as sulci
(central sulcus)
What is grey matter?
nerve cell bodies
What is white matter?
tracts of myelinated nerve fibers
What are the 2 types nerves?
- sensory nerves - info to CNS
sensory=afferent (towards) - motor nerves -info away from CNS
motor=efferent (away from)
examples of sensory information
- olfactory
- pain
- touch
- temperature
- proioception ( limb position)
- vision
examples of motor information
- effector muscles ( skeletal, cardiac, smooth)
2. glands (bladder, adrenal medulla)
What are the 2 classification of nerves.
- somatic nerves
2. visceral nerves
What are the functions of somatic nerves ( in terms of sensory and motor neurons)
- sensory info is consciously perceived
- motor action is voluntary
- single neuron connection
What are the functions of visceral nerves ( in terms of sensory and motor neurons)
- sensory info is unconscious
- motor action is involuntary
- multiple connections in CNS
Draw the autonomic and somatic nervous system
L13, pg 9b
What are the 2 autonomic divisions
- sympathetic division
2. parasympathetic division
What is the sympathetic division involved in?
- fight or flight
- catabolic reactions
- mobilize stored energy
What is the parasympathetic division involved in?
- rest and relax
- anabolic
- growth and tissue repair
Daw the midbrain,ganglion,cervical, thoracic lumbar and sacral connections
L13 pg 11
What is the similarities between the sympathetic and parasympathetic system?
have chain of cells located outside the spinal cord (ganglion)
What are the differences between the sympathetic and parasympathetic system?
- function (catabolic vs anabolic)
- origin of the nerve cell bodies
parasympathetic: cervical, sacral
sympathetic: thoracic,lumbar
What are the 3 categories of nervous tissues?
- neurons
- glia
- support cells
What are glia cells?
- non-excitable cells of neural origin
- enhance transmission efficiency
- wrap around axons
What are support cells?
- blood vessels (endothelium/fibroblast)
2. microglia ( immune cells of the CNS)
What is in the cell body of the neuron?
- prominent nucleolus (makes ribosome)
- cytoplasm: cytoskeleton, organelles
- nissl substance ribosome rich RER
- has dendrites and axon
What is a Nissl stain?
1.reacts with acid ( DNA,RNA, tRNA,rRNA)
What are the 4 major parts of the cell?
- soma (cell body)
- dendrites (receptive region)
- axons (conductive region)
- terminal ( synaptic ending)
Draw a nerve cell – focus on the cell body
pg 15
What is the alternative name of a cell body of a nerve?
perikaryon
What are dendrites? (function)
1, receptive region of the cell 2. conductive impulses towards the cell 3. some contents similar to soma: have mitochondria,SER, microtubules,neurofilaments 4. lack of golgi complex
What are axons?(function)
- conductive region of the cell
2.send impulses away from cell body
3.mitochondria, SER
4.no RER - microtubule: axonal transport (BIDIRECTIONAL)
moves vesicles and proteins
recycles structural components
anterograde and retrograde transport
What is the effector region in the axon terminal?
neuron contact between target gland, muscle or neuron
What are the 3 synapse in the axon terminal?
- pre-synaptic terminal (delivers NT)
- post-synaptic terminal (receives NT)
- synaptic cleft (intracellular space)