Synapses Flashcards
What is the term used to describe the means by which neurones communicate with each other
Synapse
List the names of three different types synaptic arrangements in the CNS
Axo-dendritic
Axo-somatic
Axon-axonal
Name the functional type that has Gap junctions, low resistance bridges and ephaptic transmission
Electrical
Name the functional type that has a pre-synaptic neuron containing vesicles and electron- dense plaques on both membranes
Chemical
Name the functional type that has 2-way traffic of electrical and chemical synapses, which is only found centrally
Reciprocal or Conjoint
How many synapses make up the CNS
2 x 10^14 synapses
How many synaptic contacts make up the CNS
2000
How many synapses are present on each synaptic contact
10,000
What neurotransmitter is stored in clear, spheroid vesicles; cholinergic synapses.
ACH
What neurotransmitter is stored in spherical dense-core vesicles; Adrenergic/ Noradrenergic Synapses
Epinephrine (E), Nor- epinephrine (NE), Serontonin (5-HT)
What neurotransmitter is stored in flattened, clear vesicles; inhibitory synapses
Glycine, Gamma-aminobutyric acid, amino acid
What neurotransmitter is stored in large dense core vesicles
Peptides
What neurotransmitter contains NO, CO
Gaseous neurotransmitters
True or False, Neurotransmission is a two way process that is necessary for orderly neural function
False, it is one way process
True or False, Single stimulus applied to a sensory neurone leads to a propagated AP in the post-synaptic neurone.
False, It doesn’t
How much time is the synaptic delay after afferent impulse
0.5ms
What type of polerizations are produced in post-synaptic cells
Transient partial depolarizatons or hyper polarisations
ESP’s are all or nothing responses
False
What process generates a full-fledged action potential
Summation
What type of potential increase the excitability of the postsynaptic membrane
ESPs
What are the two types of summations
Spatial and Temporal
Which type of summation excite different synaptic knobs simultaneously
Spatial Summation
Which type of summation Increases frequency of stimulation to the same synaptic knob
Temporal Summation
True or False, Spatial Summation EPSPs form simultaneously in adjacent areas of the post-synaptic membrane
True
True or False, Temporal Summation causes new EPSPs to form before previous ones have decayed
True
True or False, Only Spatial summation results in post synaptic inhibition or direct inhibition
False, Both spatial and temporal summation result in Postsynaptic Inhibition or Direct inhibition
What type of inhibition occurs @ axo-axonic synapses in CNS
Pre-synaptic Inhibition
What type of inhibition occurs for negative feed-back involved in “gating” of pain transmission
Indirect Inhibition
True or False, In Direct Inhibition, Afferent fibres from the skeletal muscle excite motor neurones supplying only protagonist muscles
False, they also provide reciprocal innervation to antagonist muscles
What is the term given to a decrease in the expected response due to pre-synaptic neurones sharing the same post-synaptic neurones
Occlusion
What is the term given when the response to the combined presentation of 2 stimuli = sum of those produced when each stimulus is given separately
Summation
What is the term given when the response is more than that evoked by one stimulus, but less than the sum of the 2 responses
Occlusion
what is the term given when The response to the combination of 2 stimuli exceeds the sum of the responses to separate presentations
Facilitation
