nervous system Flashcards
function of the nervous system
controls the body by communicating with the various parts
- foundation of our conscious experience, personality and behaviour
2 divisions of the nervous system
CNS-brain/spinal cord
peripheral nervous system-cranial and spinal nerves. afferent(sensory) and efferent (motor)
sensory division subunits
visceral sensory division: internal environment-carries info from the organs of the thoracic and abdominal cavity
somatic sensory division: external environment-receptors in skin. position/movement: muscles, bones and joints
motor division
-visceral motor division: autonomic nervous system. involuntary. sympathetic and parasympathetic
- somatic motor division- voluntary: carries signals to skeletal muscles
2 cells of nervous tissue
neurons and neuroglia
neuroglia of cns and functions
-astrocytes: nutrient/repair
- oligodendrocytes: myelinate neurons
- microglia: macrophages
- ependymal cells: specialized epithelial cells
neuroglia of pns
schwann cells- myelinate neurons
satellite cells- regulate external environment
what is a neuron
basic functional unit of the nervous system
properties of neurons
-excitability (irritability)
- conductivity
- secretion…axon terminals release neurotransmitters
neuron classification-structure and function
- multipolar neurons-away from CNS
- bipolar neurons - special senses
- unipolar neurons- impulses to CNS
afferent (sensory) neurons
from tissues conduct impulses to cns
efferent (motor) neurons
impulses away from CNS to tissues
interneurons
in cns
90% of neurons
connect sensory and motor pathways
nucleus
clusters of cell bodies in CNS (grey matter)
ganglion
cluster of cell bodies in the PNS
