8a. The Nervous System Flashcards
(31 cards)
define nerve
bundle of axons (or nerve fibres) and their sheaths
5 functions of the nervous system
receive sensory output
integrate information
motor output
maintain homeostasis
establish and maintain mental activity
how many pairs of cranial and spinal nerves are there?
cranial - 12 pairs
spinal - 31 pairs
why are there nerve plexus within the walls of the digestive system?
Sensory neurons connect the digestive tract to CNS
ANS motor neurons connect CNS to digestive tract
2 functions of the enteric nervous system
Stimulate/Inhibits smooth muscle contraction
Stimulate/inhibit gland secretions
Detect changes in content of lumen.
what type of control is the Somatic NS under?
voluntary, conscious control
what type of control is the Autonomic NS under?
involuntary, unconscious control
where do the action potentials from somatic NS travel to?
skeletal muscles
where do the action potentials from autonomic NS travel to?
smooth or cardiac muscle and glands
which nervous system acts with a two neuron and two synapse system?
autonomic nervous system
what does the sensory/afferent division detect?
Detects external and internal environmental stimuli
what does the motor/efferent division transmit?
Transmits electric signals from CNS to effector (muscles/glands)
where is the cell body in a the sensory division located?
Cell body of sensory neuron outside CNS (dorsal root ganglion)
where is the cell body in a the motor division located?
Cell body of motor neuron located in CNS
what division of the autonomic nervous system produces the fight or flight response?
sympathetic
which division of the autonomic system has a longer neuron response?
parasympathetic
how many different types of neuroglia are there, and where are they located?
4 CNS
2 PNS
what is a dendrite and what is its function?
Highly branched extensions of the cell body
Generate electric current when stimulated
what type of nerve cell has one cell body?
multipolar neuron
structure of a bipolar neuron
One cell body and two processes, a dendrite and an axon
where are bipolar neurons found?
Retina of eye, nasal cavity
what type of nerve cell are sensory neurons made of?
unipolar neurons
what type of nerve cell are motor neurons and interneurons made of?
multipolar neurons
function of interneuron
Conduct action potential within CNS from one neuron to another
