Nervous system Flashcards
what are the 3 main functions of the nervous system?
- collect sensory input
- process sensory input
- respond to sensory input
what is a neuron, what are the 3 main parts, what are their main functions/characteristics?
a neuron is a nerve cell.
- cell body
- serves regular cell function - dendrites
- short branched fibers off of cell body
- conducts impulses TOWARDS cell body - axon
- usually long thin fibers
- conducts impulses AWAY from cell body
what is a nervous system made of?
neurons all linked together
what is a myelin sheath, what is its function?
- white fatty coating around axons of neuron cells
- acts like an insulator
- increases the speed of nerve impulse conduction
what are 3 types of neurons?
- sensory
- relay
- motor
What is a sensory neuron?
receptor -> CNS (central nervous system)
- converts external stimuli (or internal conditions) to internal electrical impulses
- converts stimuli to electrical impulses
what is a relay neuron?
CNS -> CNS
- found in brain and spinal cord
- found between sensory and motor neurons and allows them to communicate
- interprets electrical impulses and connects the appropriate motor neurons
what is a motor neuron?
CNS -> effector
- transmit impulses from the spinal cord to skeletal and smooth muscles
- takes information from relay neuron, and carries out task
groups of cell bodies in the PNS are called:
ganglia
groups of cell bodies in the CNS are called:
nuclei, or grey matter
groups of axons in the CNS are called:
tracts, or white matter
groups of axons in the PNS are called:
nerves
what are the 8 systems in the organization of the nervous system?
- CNS
- PNS
- Afferent
- Efferent
- somatic
- Autonomic
- Sympathetic
- Parasympathetic
what does the CNS include?
Brain
Spinal cord
what does the PNS include?
Sensory receptors
Cranial nerves
Spinal nerves
Ganglia