Structure and Function of the Nervous System and Neuroglia Flashcards
Nervous system organisation
The afferent and efferent divisions of PNS each have two sub-divisions as well
A = SENSORY (SOMATIC) STIMULI, VISCERAL
E = SOMATIC NS, AUTONOMIC NS
The efferent division of the PNS control “effector organs”
SOMATIC NS > MOTOR NEURONS > SKELETAL MUSCLE
VOLUNTARY
AUTONOMIC NS = SYMPATHETIC AND PARASYMPATHETIC NS > SMOOTH AND CARDIAC MUSCLE , GLANDS
INVOLUNTARY
TYPE OF AXONS
ANAXONIC = IN THE BRAIN - DON’T KNOW AXON AND DENDRITE
RECEIVES INFO AND SENDS IT TO A PARTICULAR NEURON
= PROCESSOR
, BIPOLAR = CNS AS INTERNEURONS OR IN BRAIN
, UNIPOLAR = DORSAL SPINAL CORD
, MULTIPOLAR
CAN E 1MM TO 1M LONG
DENDRITES
INCREASE NUMBER OF IMPUTS
THROUGH SYNAPSES
AP
ACTION POTENTIALS HAVE UNIDIRECTIONAL FLOW
SATELITE CELLS
SURROND NEURON CELL BODIES IN GANGLIA,
REGULATE O2, C02, NUTRIENT ANDNEUROTRANSMITTER LVLS AROUND NEURONS IN GANGLIA
IN PNS
SCHAWN CELLS
IN PNS
SURROUND ALL AXONS IN PNS, RESPONSIBLE FOR MYELINATION OF PERIPHERAL AXONS, INVOLVED IN INJURY REPAIR
OLIOGODENROCYTES
IN CNS
PROVIDE STRUCTURAL FRAMEWORK
MYLENATE CNS AXONS
ASTROCYTES
IN CNS
MAIN BLOOD-BRAIN BARRIER, REGULATE ION, NUTRIENT AND DISSOLVED GAS ABSORBTION, STRUCTURAL FRAMEWORK
ABSORBS AND RECYCLES NEUROTRANSMITTERS
FORMS SCAR TISSUE AFTER INJRUY
MICROGLIA
IN CNS
REMOVES CELL DEBRIS, WASTE AND PATHOGENS BY PHAGOCYTES
EPENDYMAL CELLS
IN CNS
LINE BRAIN VENTRICLES AND CENTRAL CANAL IN SPINAL CORD, ASSISTS IN REGULATING, MONITORING AND PRODUCING CSF.
ROLE OF PROTEINS
proteins make membrane leaky so myelin overcomes it