Test 2 terms Flashcards
plasticity
ability of synaptic function to change depending upon antecedent activity
facilitation
rapid increase in amplitude of post-synaptic potentials following a train of stimuli. 2nd EPSP is bigger than the first, etc.
depression
causes neurotransmitter release to decline during sustained synaptic activity. This depletes the pool of releasable vesicles.
augmentation
increase in the amount of transmitter released from the presynaptic terminal lasting a few seconds.
potentiation
increase in the amount of transmitter released from the presynaptic terminal lasting minutes (post tetanic potentiation).
associative learning
formation of associations among stimuli and/or repsonses
classical conditioning
a neutral stimulus (CS - bell) is paired with a stimulus that elicits a response (US - meat powder)
Instrumental (operant) conditioning
an organism learns to associate consequences with its own behavior. delivery of a reinforcing stimulus is contingent upon expression of a designated behavior.
habituation
reduction in a response to a stimulus that is delivered repeatedly
dishabituation
recovery of a habituated response due to presentation of another strong stimulus
sensitization
enhancement of a response produced by presentation of a strong stimulus
L7
motor neuron that synapses with the gill muscle, the site of which habituation appears to occur
L29
interneuron that releases serotonin in response to the head shock. this activates GPCRs that are linked to CAMP production, which activates PKA which phosphorylates and CLOSES K channels. closing K channels decreases K conductance and prolongs the AP and allows more Ca inside.
Long-term potentiation
long lasting enhancement of the strength of stimulated synapses. LTP is input specific, the input only affects the pathway it is associated with. membrane potential of postsynaptic cell determines if LTP will occur. AMPA and NMDA receptors.
long-term depression
persistent weakening of synapses based upon recent patterns of activity
myosin
long coiled tail and globular head which has ATPase activity. Think filament of muscle.
actin
globular, thin filaments of muscle
tropomyosin
rod shaped, interacts with troponin to hide actin
troponin
protein complex that associates with tropomyosin to form a barrier to formation of cross-bridges between actin and myosin. when Ca binds the tropomyosin-troponin complex exposes myosin
t tubules
invagination of membrane into the sarcoplasmic reticulum that conducts the depolarization (EPP) which triggers the release of Ca
tetanus
contraction is sustained without any relaxations
asynchronous recruitment
to maintain tetanic contractions in a muscle, some motor units are contracting while others relax in order to prevent muscle fatigue and failure