Nervous System Flashcards
The Nervous System
One of the two major control systems of the body mediating systemic homeostatic processes
skipped
what homeostatic processes does the NS mediate? (4)
muscle contraction
integration of blood oxygen, carbon dioxide, and pH levels via respiratory activity
regulation of volumes and pressures in the circulation via cardiovascular and urinary function
digestive system motility and secretion
the NS works along with — to Maintain Systemic
Homeostasis
Endocrine System (ES)
NS is — fix to homeostatic disturbance and ES is —
quick
slower long term maintenance
NS Functional unit =
Neurons
Neuroglia =
support cells for neurons
NS uses a combination of (2) to
communicate information around body
chemical and electrical signals
dendrites are simulated by (2)
environmental changes or the activities of other cells
cell body
contains the nucleus and mitochondria, ribosomes, and other organelles and inclusions
axon
conducts nerve impulse (AP) toward synaptic terminals
synaptic terminals affect
another neuron or effector organ (muscle or gland)
nissl bodies
clusters of ribosomes found in the cell body
Many neurons have axons
that are —
myelinated
— formed by neuroglia cells
Internodes
– form myelin for axons in CNS
Oligodendrocytes
– form myelin for axons in PNS
Schwann cells
Internodes separated by small
segments of axon not covered
in myelin –
Nodes of Ranvier
function of Nodes of Ranvier
Speed up the rate of nerve impulse conduction (Saltatory conduction)
types of neurons (structural classification) (4)
anaxonic
bipolar
pseudo unipolar
multipolar
Types of Neurons (Functional Classification) (3)
sensory
motor
interneurons
Sensory Neurons (pseudounipolar neurons, bipolar) (4)
Afferent division of PNS
Carry sensory information from reflex receptor to CNS
Dendrites/Cell body in PNS
Axons typically myelinated and extend into CNS
Motor Neurons (Multipolar neurons) (4)
Efferent division of PNS
Carry motor commands from CNS to EFFECTORS
Dendrites/Cell body in CNS
Axons typically myelinated, extend into PNS and synapse
with effectors
Interneurons (Multipolar, Anaxonic) (3)
Found only in the CNS
Carry information from one neuron to another
Integration
Information flows in
one direction