NERVOUS SYSTEM_PPT 1 (LEC) Flashcards
PPT 1
5 Functions of the Nervous System
Sensory Input
Integration
Control of Muscles and glands
Homeostasis
Center for Mental Activities
Two anatomical divisions
CNS
PNS
Consist of spinal cord and brain
Central Nervous System
Consist of sensory receptors and nerves
Peripheral nervous system
It detects stimuli and transmits information to the CNS
PNS
It processes, integrates, stores and responds to information from the PNS
CNS
2 major divisions of motor division
Autonomic Nervous System
Somatic Nervous System
Innervates skeletal muscle
Somatic Nervous System
Innervates cardiac muscle, smooth muscle, glands
Autonomic nervous system
Fight/ or flight division
most active during physical activity
Sympathetic division
Parasympathetic division
resting functions
controls the digestive system
Enteric nervous system
excitable cells that transmit electrical signals
neurons
3 components of neuron
cell body (soma)
dendrites
axon
what is the function of soma?
- primary site of protein synthesis
- Golgi, mitochondria and other organelles are present
- no centrioles / amitotic
what is the function of dendrites?
conduct electric signals toward the cell body
what is the function of axon?
transmit action potentials to other cells
Clusters of cell bodies in the CNS is called _________
nuclei
Clusters of cell bodies in the PNS is called _________
ganglia
___________ is the part of the neuron where the axon originates
trigger zone
JUNCTION between a nerve cell and another cell
synapse
Enumerate and differentiate the 3 types of neurons
Multipolar neurons - have several dendrites and a single axon
Bipolar neurons - single axon and dendrite
unipolar neurons - single axon
supporting cells that promote health and growth and provide a supportive scaffolding for neurons
glial cells
what are the glial cells of the CNS
- astrocytes
- microglial
- ependymal cells
- oligodendrocytes
glial cells of the pns
- satellite cells
- schwann cells
“star cell”
“blood brain barrier”
astrocytes
it helps to circulate cerebrospinal fluid
ependymal cells
fights/ phagocytes bacteria
microglia
form myelin sheaths in CNS
oligodendrocytes
form myelin sheath in PNS
Schwann cells
support and nourish neuron cells within ganglia
satellite cells
what is the node of ranvier
these are the GAPS in the myelin sheath
whitish and fatty that protects the axon, electrically insulate fibers and increases the speed of nerve impulse
myelin
conduct action potentials slowly
unmyelinated axons
myelinated axons: white matter
unmyelinated axons: ???
gray matter
electrical signals produced by cells are called ___________
action potentials
Presynaptic cell: transmits signal towards a synapse
Postsynaptic cell: ???????????
receives the signal
two types of synapse
electrical synapse
chemical synapse
a space that SEPARATES the presynaptic and postsynaptic membrane
synaptic cleft
a pathway that have MANY neurons synapsing with a FEW neurons
(many to few)
convergent pathway
a pathway that have FEW neurons synapsing with a MANY neurons
(few to many)
divergent pathway
have COLLATERAL BRANCHES of postsynaptic neurons synapsing with presynaptic neurons
oscillating circuits
Bundles of processes in the CNS
Nerve tracts
Bundles of processes in the PNS
Nerves
