HSII Ch. 8
Card Set Information
HSII Ch. 8
Central Nervous System (CNS) def.
brain & spinal cord
Peripheral Nervous System (PNS) def.
Autonomic Nervous System (ANS) def.
autonomic (involuntary motor nerves)
somatic (voluntary) motor nerves
3 main parts of a neuron
conduct impulses to cell body of a neuron
conduct impulses away from cell body to other neurons
sensory (afferent) neurons def.
conduct impulse sto spinal cord & brain
: feeling heat from a stove
motor (efferent) neurons
impulses away from brain & spinal cord to muscles & glands
: moving hand off hot stove
impulses from sensory neurons to motor neurons
glia (neuroglia) function
bring cells of nervous tissue together structurally & functionally
main types of glia in CNS
anchor sm. blood vessels to neurons
sm. cells move inflamed brain tissue carrying phagocytes
from myelin sheaths on axons in the CNS
form myelin sheats on axons of the PNS
bundle of PERIPHERAL axons
bundle of CENTRAL axons
types of tracts
tissue comp. primarily of myelinated axons
can be nerves or tracts
fibrous connective tissue
types of nerve coverings
surrounds indiv. fibers w/in a nerve
surrounds bundle (aka fascicle) of nerve fibers
surrounds entire nervea
reflex arcs def.
nerve impulses conducted from receptors to effectors over neuron pathways
contraction by a muscle or secretion by a gland
two-neuron arcs def.
consist of sensory neurons connecting in spinal cord w/motor neurons
three-neuron arcs def.
sensory neurons synapsing in spinal cord w/interneurons that synapse w/motor neurons