Nervous System Flashcards
Function of Nervous System
Controls the internal environment
Voluntary control of movement
Provides sensory info
Programming spinal cord reflexes
Memory and learning
Cell body
integrates info
Dendrites
impulses towards cell body
Axon
impulse away from cell body
covered with Schwann cells and forms myelin sheath
Synapse
contact points b/t axon of one neuron and dendrite of another
Excitatory transmitter
cause depolarization
Inhibitory transmitter
cause hyperpolarization
Norepinephrine neurotransmitter
found in PNS and CNS, Excess: associated with mania, Low: depression
Dopamine
found in CNS, Attention, Emotional behavior, Addictive behavior, parkinsons
Serotonin
found in PNS and CNS, linked with depression and irregulates circadian rhythm
Osmoreceptors
hydration/concentration
Baroreceptors
respond to pressure changes in blood vessels
Proprioceptors
provide CNS information about body position and joint angle
Muscle chemoreceptors
provide CNS info on metabolic rate of muscular activity, sensitive to chemical changes
Reflexes order of events
Afferent
interneurons in spinal cord activate motor neurons
efferent
Reciprocal inhibition
agonist contracts
antagonist relaxes
Muscle spindle
detect rate of change in muscle length
stretch reflex
Golgi Tendon Organs
monitors tension in muscle
prevents damage during excessive force generation
Vestibular apparatus
located in inner ear
maintains equilibrium and balance
sensitive to angular and linear accelerations
Somatic motor neurons of PNS
carry messages from brain/spinal cord to muscle (efferent)
Innervation ratio
number of muscle fibers per motor neuron
Brain Stem
Controls CV and respiratory system
Cerebrum
cerebral cortex
motor cortex
cerebral cortex
organizes complex move
storage of learned experiences
reception of sensory info
motor cortex
voluntary movement
cerebellum
monitoring complex movement
