Nervous System (Lecture and Laboratoty) Flashcards
bundle of many axons
that connects the CNS to sensory
receptors, muscles and glands
nerve
how many pirs of cranial nerves and spinal nerves?
12 pairs of Cranial Nerves
31 pairs of Spinal Nerves
collection of neuron
cell bodies located outside the
CNS
ganglion
what is the main division of the nervous system?
CNS - Central nervous system
PNS - peripheral nervous system
peripheral nervous system is divided into
sensory division (afferent division)
motor division (efferent division)
conduct action
potentials from
sensory receptors
to the CNS
sensory division
conduct action
potentials from
CNS to effector
organs (muscles
or glands
motor division
motor division (efferent division) is divided into
somatic nervous system
autonomic nervous system
transmits action
potentials from the
CNS to skeletal
muscles
somatic nervous system
autonomic nervous system is divided into
sympathetic nervous system
parasympathetic nervous system
transmits action potentials
from the CNS to cardiac
muscle, smooth muscle,
and glands
autonomic nervous system
what are the cells of the nervous system?
neurons
glial cells
Receive stimuli, conduct action
potentials, and transmit signals to other neurons or effector organs
neurons (nerve cells)
what are the 3 parts of the neurons
- cell body
- dendrites
- axons
- contains a nucleus - source of
information for gene expression - rough ER, golgi apparatus,
mitochondria
cell body
- short, highly branching
cytoplasmic extensions - receives stimulus from other
neurons or sensory receptors
dendrite
- a single long process extending
from the neuron cell body - transmits stimulus to a gland,
muscle, organ, or other neuro
axon
area where the axon
leaves the neuron cell
body
axon hillock
conduct action potentials
towards the CNS
axon of sensory neurons
conduct action potentials
away the CNS
axon of motor neurons
types of neurons base on functional classifications
Sensory Neurons
Motor Neurons
Interneurons
types of neurons base on structural classification
multipolar
bipolar
pseudo-unipolar
*many dendrites and a single axon
*most CNS and most motor neurons
multipolar
*have 2 processes (one dendrite and one axon)
*some sensory organs (Eye and nasal cavity)
bipolar
*single processes extending from cell body
*one axon and dendrite-like receptors
*most sensory neurons
pseudo-unipolar
protective wrapping around brain and
spinal cord
meninges
specialized wrapping around axons
myelin sheath
gaps in myelin sheath where action
potentials develop
nodes of ranvier
nerve tissue exists as?
gray or white matter
consist of group of neuron cell bodies and their dendrites
gray matter
consist of bundles of parallel axons and their myelin sheaths, which are whitish in color
white matter
inferior end of the spinal cord; spinal nerves exiting there resemble a
horse’s tail
Cauda equina
where neurons of several spinal
nerves come together and
intermingle
plexuses
